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12545 Commits
Author | SHA1 | Message | Date | |
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Omar Sandoval
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93781325da |
lockdep: fix fs_reclaim annotation
While revisiting my Btrfs swapfile series [1], I introduced a situation
in which reclaim would lock i_rwsem, and even though the swapon() path
clearly made GFP_KERNEL allocations while holding i_rwsem, I got no
complaints from lockdep. It turns out that the rework of the fs_reclaim
annotation was broken: if the current task has PF_MEMALLOC set, we don't
acquire the dummy fs_reclaim lock, but when reclaiming we always check
this _after_ we've just set the PF_MEMALLOC flag. In most cases, we can
fix this by moving the fs_reclaim_{acquire,release}() outside of the
memalloc_noreclaim_{save,restore}(), althought kswapd is slightly
different. After applying this, I got the expected lockdep splats.
1: https://lwn.net/Articles/625412/
Link: http://lkml.kernel.org/r/9f8aa70652a98e98d7c4de0fc96a4addcee13efe.1523778026.git.osandov@fb.com
Fixes:
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Yang Shi
|
89fdcd262f |
mm: shmem: make stat.st_blksize return huge page size if THP is on
Since tmpfs THP was supported in 4.8, hugetlbfs is not the only filesystem with huge page support anymore. tmpfs can use huge page via THP when mounting by "huge=" mount option. When applications use huge page on hugetlbfs, it just need check the filesystem magic number, but it is not enough for tmpfs. Make stat.st_blksize return huge page size if it is mounted by appropriate "huge=" option to give applications a hint to optimize the behavior with THP. Some applications may not do wisely with THP. For example, QEMU may mmap file on non huge page aligned hint address with MAP_FIXED, which results in no pages are PMD mapped even though THP is used. Some applications may mmap file with non huge page aligned offset. Both behaviors make THP pointless. statfs.f_bsize still returns 4KB for tmpfs since THP could be split, and it also may fallback to 4KB page silently if there is not enough huge page. Furthermore, different f_bsize makes max_blocks and free_blocks calculation harder but without too much benefit. Returning huge page size via stat.st_blksize sounds good enough. Since PUD size huge page for THP has not been supported, now it just returns HPAGE_PMD_SIZE. Hugh said: : Sorry, I have no enthusiasm for this patch; but do I feel strongly : enough to override you and everyone else to NAK it? No, I don't feel : that strongly, maybe st_blksize isn't worth arguing over. : : We did look at struct stat when designing huge tmpfs, to see if there : were any fields that should be adjusted for it; but concluded none. : Yes, it would sometimes be nice to have a quickly accessible indicator : for when tmpfs has been mounted huge (scanning /proc/mounts for options : can be tiresome, agreed); but since tmpfs tries to supply huge (or not) : pages transparently, no difference seemed right. : : So, because st_blksize is a not very useful field of struct stat, with : "size" in the name, we're going to put HPAGE_PMD_SIZE in there instead : of PAGE_SIZE, if the tmpfs was mounted with one of the huge "huge" : options (force or always, okay; within_size or advise, not so much). : Though HPAGE_PMD_SIZE is no more its "preferred I/O size" or "blocksize : for file system I/O" than PAGE_SIZE was. : : Which we can expect to speed up some applications and disadvantage : others, depending on how they interpret st_blksize: just like if we : changed it in the same way on non-huge tmpfs. (Did I actually try : changing st_blksize early on, and find it broke something? If so, I've : now forgotten what, and a search through commit messages didn't find : it; but I guess we'll find out soon enough.) : : If there were an mstat() syscall, returning a field "preferred : alignment", then we could certainly agree to put HPAGE_PMD_SIZE in : there; but in stat()'s st_blksize? And what happens when (in future) : mm maps this or that hard-disk filesystem's blocks with a pmd mapping - : should that filesystem then advertise a bigger st_blksize, despite the : same disk layout as before? What happens with DAX? : : And this change is not going to help the QEMU suboptimality that : brought you here (or does QEMU align mmaps according to st_blksize?). : QEMU ought to work well with kernels without this change, and kernels : with this change; and I hope it can easily deal with both by avoiding : that use of MAP_FIXED which prevented the kernel's intended alignment. [akpm@linux-foundation.org: remove unneeded `else'] Link: http://lkml.kernel.org/r/1524665633-83806-1-git-send-email-yang.shi@linux.alibaba.com Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Chintan Pandya
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05e3ff9505 |
mm: vmalloc: pass proper vm_start into debugobjects
Client can call vunmap with some intermediate 'addr' which may not be the start of the VM area. Entire unmap code works with vm->vm_start which is proper but debug object API is called with 'addr'. This could be a problem within debug objects. Pass proper start address into debug object API. [akpm@linux-foundation.org: fix warning] Link: http://lkml.kernel.org/r/1523961828-9485-3-git-send-email-cpandya@codeaurora.org Signed-off-by: Chintan Pandya <cpandya@codeaurora.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yisheng Xie <xieyisheng1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Chintan Pandya
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f3c01d2f3a |
mm: vmalloc: avoid racy handling of debugobjects in vunmap
Currently, __vunmap flow is, 1) Release the VM area 2) Free the debug objects corresponding to that vm area. This leave some race window open. 1) Release the VM area 1.5) Some other client gets the same vm area 1.6) This client allocates new debug objects on the same vm area 2) Free the debug objects corresponding to this vm area. Here, we actually free 'other' client's debug objects. Fix this by freeing the debug objects first and then releasing the VM area. Link: http://lkml.kernel.org/r/1523961828-9485-2-git-send-email-cpandya@codeaurora.org Signed-off-by: Chintan Pandya <cpandya@codeaurora.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yisheng Xie <xieyisheng1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Chintan Pandya
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82a2e924ff |
mm: vmalloc: clean up vunmap to avoid pgtable ops twice
vunmap does page table clear operations twice in the case when DEBUG_PAGEALLOC_ENABLE_DEFAULT is enabled. So, clean up the code as that is unintended. As a perf gain, we save few us. Below ftrace data was obtained while doing 1 MB of vmalloc/vfree on ARM64 based SoC *without* this patch applied. After this patch, we can save ~3 us (on 1 extra vunmap_page_range). CPU DURATION FUNCTION CALLS | | | | | | | 6) | __vunmap() { 6) | vmap_debug_free_range() { 6) 3.281 us | vunmap_page_range(); 6) + 45.468 us | } 6) 2.760 us | vunmap_page_range(); 6) ! 505.105 us | } [cpandya@codeaurora.org: v3] Link: http://lkml.kernel.org/r/1525176960-18408-1-git-send-email-cpandya@codeaurora.org Link: http://lkml.kernel.org/r/1523876342-10545-1-git-send-email-cpandya@codeaurora.org Signed-off-by: Chintan Pandya <cpandya@codeaurora.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Laura Abbott <labbott@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Yisheng Xie <xieyisheng1@huawei.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Wei Yang
|
08994b2467 |
mm/sparse.c: pass the __highest_present_section_nr + 1 to alloc_func()
In commit
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Wei Yang
|
d538c164fc |
mm/sparse.c: check __highest_present_section_nr only for a present section
When searching a present section, there are two boundaries: * __highest_present_section_nr * NR_MEM_SECTIONS And it is known, __highest_present_section_nr is a more strict boundary than NR_MEM_SECTIONS. This means it would be necessary to check __highest_present_section_nr only. Link: http://lkml.kernel.org/r/20180326081956.75275-2-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Huang Ying
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688272809f |
mm, gup: prevent pmd checking race in follow_pmd_mask()
mmap_sem will be read locked when calling follow_pmd_mask(). But this cannot prevent PMD from being changed for all cases when PTL is unlocked, for example, from pmd_trans_huge() to pmd_none() via MADV_DONTNEED. So it is possible for the pmd_present() check in follow_pmd_mask() to encounter an invalid PMD. This may cause an incorrect VM_BUG_ON() or an infinite loop. Fix this by reading the PMD entry into a local variable with READ_ONCE() and checking the local variable and pmd_none() in the retry loop. As Kirill pointed out, with PTL unlocked, the *pmd may be changed under us, so reading it directly again and again may incur weird bugs. So although using *pmd directly other than for pmd_present() checking may be safe, it is still better to replace them to read *pmd once and check the local variable multiple times. When PTL unlocked, replace all *pmd with local variable was suggested by Kirill. Link: http://lkml.kernel.org/r/20180419083514.1365-1-ying.huang@intel.com Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Roman Gushchin
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5f93ad6743 |
mm: treat memory.low value inclusive
If memcg's usage is equal to the memory.low value, avoid reclaiming from this cgroup while there is a surplus of reclaimable memory. This sounds more logical and also matches memory.high and memory.max behavior: both are inclusive. Empty cgroups are not considered protected, so MEMCG_LOW events are not emitted for empty cgroups, if there is no more reclaimable memory in the system. Link: http://lkml.kernel.org/r/20180406122132.GA7185@castle Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Roman Gushchin
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230671533d |
mm: memory.low hierarchical behavior
This patch aims to address an issue in current memory.low semantics, which makes it hard to use it in a hierarchy, where some leaf memory cgroups are more valuable than others. For example, there are memcgs A, A/B, A/C, A/D and A/E: A A/memory.low = 2G, A/memory.current = 6G //\\ BC DE B/memory.low = 3G B/memory.current = 2G C/memory.low = 1G C/memory.current = 2G D/memory.low = 0 D/memory.current = 2G E/memory.low = 10G E/memory.current = 0 If we apply memory pressure, B, C and D are reclaimed at the same pace while A's usage exceeds 2G. This is obviously wrong, as B's usage is fully below B's memory.low, and C has 1G of protection as well. Also, A is pushed to the size, which is less than A's 2G memory.low, which is also wrong. A simple bash script (provided below) can be used to reproduce the problem. Current results are: A: 1430097920 A/B: 711929856 A/C: 717426688 A/D: 741376 A/E: 0 To address the issue a concept of effective memory.low is introduced. Effective memory.low is always equal or less than original memory.low. In a case, when there is no memory.low overcommittment (and also for top-level cgroups), these two values are equal. Otherwise it's a part of parent's effective memory.low, calculated as a cgroup's memory.low usage divided by sum of sibling's memory.low usages (under memory.low usage I mean the size of actually protected memory: memory.current if memory.current < memory.low, 0 otherwise). It's necessary to track the actual usage, because otherwise an empty cgroup with memory.low set (A/E in my example) will affect actual memory distribution, which makes no sense. To avoid traversing the cgroup tree twice, page_counters code is reused. Calculating effective memory.low can be done in the reclaim path, as we conveniently traversing the cgroup tree from top to bottom and check memory.low on each level. So, it's a perfect place to calculate effective memory low and save it to use it for children cgroups. This also eliminates a need to traverse the cgroup tree from bottom to top each time to check if parent's guarantee is not exceeded. Setting/resetting effective memory.low is intentionally racy, but it's fine and shouldn't lead to any significant differences in actual memory distribution. With this patch applied results are matching the expectations: A: 2147930112 A/B: 1428721664 A/C: 718393344 A/D: 815104 A/E: 0 Test script: #!/bin/bash CGPATH="/sys/fs/cgroup" truncate /file1 --size 2G truncate /file2 --size 2G truncate /file3 --size 2G truncate /file4 --size 50G mkdir "${CGPATH}/A" echo "+memory" > "${CGPATH}/A/cgroup.subtree_control" mkdir "${CGPATH}/A/B" "${CGPATH}/A/C" "${CGPATH}/A/D" "${CGPATH}/A/E" echo 2G > "${CGPATH}/A/memory.low" echo 3G > "${CGPATH}/A/B/memory.low" echo 1G > "${CGPATH}/A/C/memory.low" echo 0 > "${CGPATH}/A/D/memory.low" echo 10G > "${CGPATH}/A/E/memory.low" echo $$ > "${CGPATH}/A/B/cgroup.procs" && vmtouch -qt /file1 echo $$ > "${CGPATH}/A/C/cgroup.procs" && vmtouch -qt /file2 echo $$ > "${CGPATH}/A/D/cgroup.procs" && vmtouch -qt /file3 echo $$ > "${CGPATH}/cgroup.procs" && vmtouch -qt /file4 echo "A: " `cat "${CGPATH}/A/memory.current"` echo "A/B: " `cat "${CGPATH}/A/B/memory.current"` echo "A/C: " `cat "${CGPATH}/A/C/memory.current"` echo "A/D: " `cat "${CGPATH}/A/D/memory.current"` echo "A/E: " `cat "${CGPATH}/A/E/memory.current"` rmdir "${CGPATH}/A/B" "${CGPATH}/A/C" "${CGPATH}/A/D" "${CGPATH}/A/E" rmdir "${CGPATH}/A" rm /file1 /file2 /file3 /file4 Link: http://lkml.kernel.org/r/20180405185921.4942-2-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Roman Gushchin
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bbec2e1517 |
mm: rename page_counter's count/limit into usage/max
This patch renames struct page_counter fields: count -> usage limit -> max and the corresponding functions: page_counter_limit() -> page_counter_set_max() mem_cgroup_get_limit() -> mem_cgroup_get_max() mem_cgroup_resize_limit() -> mem_cgroup_resize_max() memcg_update_kmem_limit() -> memcg_update_kmem_max() memcg_update_tcp_limit() -> memcg_update_tcp_max() The idea behind this renaming is to have the direct matching between memory cgroup knobs (low, high, max) and page_counters API. This is pure renaming, this patch doesn't bring any functional change. Link: http://lkml.kernel.org/r/20180405185921.4942-1-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Stefan Agner
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1c4bc43ddf |
mm/memblock: introduce PHYS_ADDR_MAX
So far code was using ULLONG_MAX and type casting to obtain a phys_addr_t with all bits set. The typecast is necessary to silence compiler warnings on 32-bit platforms. Use the simpler but still type safe approach "~(phys_addr_t)0" to create a preprocessor define for all bits set. Link: http://lkml.kernel.org/r/20180406213809.566-1-stefan@agner.ch Signed-off-by: Stefan Agner <stefan@agner.ch> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Laurent Dufour
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00b3a331fd |
mm: remove odd HAVE_PTE_SPECIAL
Remove the additional define HAVE_PTE_SPECIAL and rely directly on CONFIG_ARCH_HAS_PTE_SPECIAL. There is no functional change introduced by this patch Link: http://lkml.kernel.org/r/1523533733-25437-1-git-send-email-ldufour@linux.vnet.ibm.com Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Christophe LEROY <christophe.leroy@c-s.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Laurent Dufour
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3010a5ea66 |
mm: introduce ARCH_HAS_PTE_SPECIAL
Currently the PTE special supports is turned on in per architecture header files. Most of the time, it is defined in arch/*/include/asm/pgtable.h depending or not on some other per architecture static definition. This patch introduce a new configuration variable to manage this directly in the Kconfig files. It would later replace __HAVE_ARCH_PTE_SPECIAL. Here notes for some architecture where the definition of __HAVE_ARCH_PTE_SPECIAL is not obvious: arm __HAVE_ARCH_PTE_SPECIAL which is currently defined in arch/arm/include/asm/pgtable-3level.h which is included by arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set. So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE. powerpc __HAVE_ARCH_PTE_SPECIAL is defined in 2 files: - arch/powerpc/include/asm/book3s/64/pgtable.h - arch/powerpc/include/asm/pte-common.h The first one is included if (PPC_BOOK3S & PPC64) while the second is included in all the other cases. So select ARCH_HAS_PTE_SPECIAL all the time. sparc: __HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) && defined(__arch64__) which are defined through the compiler in sparc/Makefile if !SPARC32 which I assume to be if SPARC64. So select ARCH_HAS_PTE_SPECIAL if SPARC64 There is no functional change introduced by this patch. Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Suggested-by: Jerome Glisse <jglisse@redhat.com> Reviewed-by: Jerome Glisse <jglisse@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: David S. Miller <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <albert@sifive.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Christophe LEROY <christophe.leroy@c-s.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Wei Yang
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e69438596b |
mm/page_alloc: remove realsize in free_area_init_core()
Highmem's realsize always equals to freesize, so it is not necessary to spare a variable to record this. Link: http://lkml.kernel.org/r/20180413083859.65888-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Mike Kravetz
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5d752600a8 |
mm: restructure memfd code
With the addition of memfd hugetlbfs support, we now have the situation where memfd depends on TMPFS -or- HUGETLBFS. Previously, memfd was only supported on tmpfs, so it made sense that the code resided in shmem.c. In the current code, memfd is only functional if TMPFS is defined. If HUGETLFS is defined and TMPFS is not defined, then memfd functionality will not be available for hugetlbfs. This does not cause BUGs, just a lack of potentially desired functionality. Code is restructured in the following way: - include/linux/memfd.h is a new file containing memfd specific definitions previously contained in shmem_fs.h. - mm/memfd.c is a new file containing memfd specific code previously contained in shmem.c. - memfd specific code is removed from shmem_fs.h and shmem.c. - A new config option MEMFD_CREATE is added that is defined if TMPFS or HUGETLBFS is defined. No functional changes are made to the code: restructuring only. Link: http://lkml.kernel.org/r/20180415182119.4517-4-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Marc-Andr Lureau <marcandre.lureau@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Mike Kravetz
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c49fcfcda8 |
mm/shmem: update file sealing comments and file checking
In preparation for memfd code restructure, update comments, definitions and function names dealing with file sealing to indicate that tmpfs and hugetlbfs are the supported filesystems. Also, change file pointer checks in memfd_file_seals_ptr to use defined interfaces instead of directly referencing file_operation structs. Link: http://lkml.kernel.org/r/20180415182119.4517-3-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Marc-Andr Lureau <marcandre.lureau@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Mike Kravetz
|
5b9c98f308 |
mm/shmem: add __rcu annotations and properly deref radix entry
Patch series "restructure memfd code", v4. This patch (of 3): In preparation for memfd code restucture, clean up sparse warnings. Most changes required adding __rcu annotations. The routine find_swap_entry was modified to properly deference radix tree entries. Link: http://lkml.kernel.org/r/20180415182119.4517-2-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Marc-Andr Lureau <marcandre.lureau@gmail.com> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Tejun Heo
|
f3a53a3a1e |
mm, memcontrol: implement memory.swap.events
Add swap max and fail events so that userland can monitor and respond to running out of swap. I'm not too sure about the fail event. Right now, it's a bit confusing which stats / events are recursive and which aren't and also which ones reflect events which originate from a given cgroup and which targets the cgroup. No idea what the right long term solution is and it could just be that growing them organically is actually the only right thing to do. Link: http://lkml.kernel.org/r/20180416231151.GI1911913@devbig577.frc2.facebook.com Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Rik van Riel <riel@surriel.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Tejun Heo
|
bb98f2c5ac |
mm, memcontrol: move swap charge handling into get_swap_page()
Patch series "mm, memcontrol: Implement memory.swap.events", v2. This patchset implements memory.swap.events which contains max and fail events so that userland can monitor and respond to swap running out. This patch (of 2): get_swap_page() is always followed by mem_cgroup_try_charge_swap(). This patch moves mem_cgroup_try_charge_swap() into get_swap_page() and makes get_swap_page() call the function even after swap allocation failure. This simplifies the callers and consolidates memcg related logic and will ease adding swap related memcg events. Link: http://lkml.kernel.org/r/20180416230934.GH1911913@devbig577.frc2.facebook.com Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Yang Shi
|
88aa7cc688 |
mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct
mmap_sem is on the hot path of kernel, and it very contended, but it is abused too. It is used to protect arg_start|end and evn_start|end when reading /proc/$PID/cmdline and /proc/$PID/environ, but it doesn't make sense since those proc files just expect to read 4 values atomically and not related to VM, they could be set to arbitrary values by C/R. And, the mmap_sem contention may cause unexpected issue like below: INFO: task ps:14018 blocked for more than 120 seconds. Tainted: G E 4.9.79-009.ali3000.alios7.x86_64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ps D 0 14018 1 0x00000004 Call Trace: schedule+0x36/0x80 rwsem_down_read_failed+0xf0/0x150 call_rwsem_down_read_failed+0x18/0x30 down_read+0x20/0x40 proc_pid_cmdline_read+0xd9/0x4e0 __vfs_read+0x37/0x150 vfs_read+0x96/0x130 SyS_read+0x55/0xc0 entry_SYSCALL_64_fastpath+0x1a/0xc5 Both Alexey Dobriyan and Michal Hocko suggested to use dedicated lock for them to mitigate the abuse of mmap_sem. So, introduce a new spinlock in mm_struct to protect the concurrent access to arg_start|end, env_start|end and others, as well as replace write map_sem to read to protect the race condition between prctl and sys_brk which might break check_data_rlimit(), and makes prctl more friendly to other VM operations. This patch just eliminates the abuse of mmap_sem, but it can't resolve the above hung task warning completely since the later access_remote_vm() call needs acquire mmap_sem. The mmap_sem scalability issue will be solved in the future. [yang.shi@linux.alibaba.com: add comment about mmap_sem and arg_lock] Link: http://lkml.kernel.org/r/1524077799-80690-1-git-send-email-yang.shi@linux.alibaba.com Link: http://lkml.kernel.org/r/1523730291-109696-1-git-send-email-yang.shi@linux.alibaba.com Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Canjiang Lu
|
05088e5de0 |
mm/slub: remove obsolete comment
The obsolete comment removed in this patch was introduced by
|
||
Mathieu Malaterre
|
a38965bf94 |
mm/slub.c: add __printf verification to slab_err()
__printf is useful to verify format and arguments. Remove the following warning (with W=1): mm/slub.c:721:2: warning: function might be possible candidate for `gnu_printf' format attribute [-Wsuggest-attribute=format] Link: http://lkml.kernel.org/r/20180505200706.19986-1-malat@debian.org Signed-off-by: Mathieu Malaterre <malat@debian.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Matthew Wilcox
|
128227e7fe |
slab: __GFP_ZERO is incompatible with a constructor
__GFP_ZERO requests that the object be initialised to all-zeroes, while
the purpose of a constructor is to initialise an object to a particular
pattern. We cannot do both. Add a warning to catch any users who
mistakenly pass a __GFP_ZERO flag when allocating a slab with a
constructor.
Link: http://lkml.kernel.org/r/20180412191322.GA21205@bombadil.infradead.org
Fixes:
|
||
Souptick Joarder
|
ab77dab462 |
fs/dax.c: use new return type vm_fault_t
Use new return type vm_fault_t for fault handler. For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno. Once all instances are converted, vm_fault_t will become a
distinct type.
commit
|
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Linus Torvalds
|
a1cdde8c41 |
4.18 Merge window pull request
This has been a quiet cycle for RDMA, the big bulk is the usual smallish driver updates and bug fixes. About four new uAPI related things. Not as much Szykaller patches this time, the bugs it finds are getting harder to fix. - More work cleaning up the RDMA CM code - Usual driver bug fixes and cleanups for qedr, qib, hfi1, hns, i40iw, iw_cxgb4, mlx5, rxe - Driver specific resource tracking and reporting via netlink - Continued work for name space support from Parav - MPLS support for the verbs flow steering uAPI - A few tricky IPoIB fixes improving robustness - HFI1 driver support for the '16B' management packet format - Some auditing to not print kernel pointers via %llx or similar - Mark the entire 'UCM' user-space interface as BROKEN with the intent to remove it entirely. The user space side of this was long ago replaced with RDMA-CM and syzkaller is finding bugs in the residual UCM interface nobody wishes to fix because nobody uses it. - Purge more bogus BUG_ON's from Leon - 'flow counters' verbs uAPI - T10 fixups for iser/isert, these are Acked by Martin but going through the RDMA tree due to dependencies -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABCgAGBQJbGEcPAAoJEDht9xV+IJsarBMQAIsAFOizycF0kQfDtvz1yHyV YjkT3NA71379DsDsCOezVKqZ6RtXdQncJoqqEG1FuNKiXh/rShR3rk9XmdBwUCTq mIY0ySiQggdeSIJclROiBuzLE3F/KIIkY3jwM80DzT9GUEbnVuvAMt4M56X48Xo8 RpFc13/1tY09ZLBVjInlfmCpRWyNgNccDBDywB/5hF5KCFR/BG/vkp4W0yzksKiU 7M/rZYyxQbtwSfe/ZXp7NrtwOpkpn7vmhED59YgKRZWhqnHF9KKmV+K1FN+BKdXJ V1KKJ2RQINg9bbLJ7H2JPdQ9EipvgAjUJKKBoD+XWnoVJahp6X2PjX351R/h4Lo5 TH+0XwuCZ2EdjRxhnm3YE+rU10mDY9/UUi1xkJf9vf0r25h6Fgt6sMnN0QBpqkTh euRZnPyiFeo1b+hCXJfKqkQ6An+F3zes5zvVf59l0yfVNLVmHdlz0lzKLf/RPk+t U+YZKxfmHA+mwNhMXtKx7rKVDrko+uRHjaX2rPTEvZ0PXE7lMzFMdBWYgzP6sx/b 4c55NiJMDAGTyLCxSc7ziGgdL9Lpo/pRZJtFOHqzkDg8jd7fb07ID7bMPbSa05y0 BU5VpC8yEOYRpOEFbkJSPtHc0Q8cMCv/q1VcMuuhKXYnfSho3TWvtOSQIjUoU/q0 8T6TXYi2yF+f+vZBTFlV =Mb8m -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma Pull rdma updates from Jason Gunthorpe: "This has been a quiet cycle for RDMA, the big bulk is the usual smallish driver updates and bug fixes. About four new uAPI related things. Not as much Szykaller patches this time, the bugs it finds are getting harder to fix. Summary: - More work cleaning up the RDMA CM code - Usual driver bug fixes and cleanups for qedr, qib, hfi1, hns, i40iw, iw_cxgb4, mlx5, rxe - Driver specific resource tracking and reporting via netlink - Continued work for name space support from Parav - MPLS support for the verbs flow steering uAPI - A few tricky IPoIB fixes improving robustness - HFI1 driver support for the '16B' management packet format - Some auditing to not print kernel pointers via %llx or similar - Mark the entire 'UCM' user-space interface as BROKEN with the intent to remove it entirely. The user space side of this was long ago replaced with RDMA-CM and syzkaller is finding bugs in the residual UCM interface nobody wishes to fix because nobody uses it. - Purge more bogus BUG_ON's from Leon - 'flow counters' verbs uAPI - T10 fixups for iser/isert, these are Acked by Martin but going through the RDMA tree due to dependencies" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (138 commits) RDMA/mlx5: Update SPDX tags to show proper license RDMA/restrack: Change SPDX tag to properly reflect license IB/hfi1: Fix comment on default hdr entry size IB/hfi1: Rename exp_lock to exp_mutex IB/hfi1: Add bypass register defines and replace blind constants IB/hfi1: Remove unused variable IB/hfi1: Ensure VL index is within bounds IB/hfi1: Fix user context tail allocation for DMA_RTAIL IB/hns: Use zeroing memory allocator instead of allocator/memset infiniband: fix a possible use-after-free bug iw_cxgb4: add INFINIBAND_ADDR_TRANS dependency IB/isert: use T10-PI check mask definitions from core layer IB/iser: use T10-PI check mask definitions from core layer RDMA/core: introduce check masks for T10-PI offload IB/isert: fix T10-pi check mask setting IB/mlx5: Add counters read support IB/mlx5: Add flow counters read support IB/mlx5: Add flow counters binding support IB/mlx5: Add counters create and destroy support IB/uverbs: Add support for flow counters ... |
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Linus Torvalds
|
6567af78ac |
Changes for 4.18:
- Strengthen inode number and structure validation when allocating inodes. - Reduce pointless buffer allocations during cache miss - Use FUA for pure data O_DSYNC directio writes - Various iomap refactorings - Strengthen quota metadata verification to avoid unfixable broken quota - Make AGFL block freeing a deferred operation to avoid blowing out transaction reservations when running complex operations - Get rid of the log item descriptors to reduce log overhead - Fix various reflink bugs where inodes were double-joined to transactions - Don't issue discards when trimming unwritten extents - Refactor incore dquot initialization and retrieval interfaces - Fix some locking problmes in the quota scrub code - Strengthen btree structure checks in scrub code - Rewrite swapfile activation to use iomap and support unwritten extents - Make scrub exit to userspace sooner when corruptions or cross-referencing problems are found - Make scrub invoke the data fork scrubber directly on metadata inodes - Don't do background reclamation of post-eof and cow blocks when the fs is suspended - Fix secondary superblock buffer lifespan hinting - Refactor growfs to use table-dispatched functions instead of long stringy functions - Move growfs code to libxfs - Implement online fs label getting and setting - Introduce online filesystem repair (in a very limited capacity) - Fix unit conversion problems in the realtime freemap iteration functions - Various refactorings and cleanups in preparation to remove buffer heads in a future release - Reimplement the old bmap call with iomap - Remove direct buffer head accesses from seek hole/data - Various bug fixes -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAlsR9dEACgkQ+H93GTRK tOv0dw//cBwRgY4jhC6b9oMk2DNRWUiTt1F2yoqr28661GPo124iXAMLIwJe1DiV W/qpN3HUz7P46xKOVY+MXaj0JIDFxJ8c5tHAQMH/TkDc49S+mkcGyaoPJ39hnc6u yikG+Hq4m0YWhHaeUhKTe8pnhXBaziz5A2NtKtwh6lPOIW+Wds51T77DJnViqADq tZzmAq8fS9/ELpxe0Th/2D7iTWCr2c3FLsW2KgbbNvQ4e34zVE1ix1eBtEzQE+Mm GUjdQhYVS1oCzqZfCxJkzR4R/1TAFyS0FXOW7PHo8FAX/kas9aQbRlnHSAQ/08EE 8Z2p3GsFip7dgmd6O6nAmFAStW6GRvgyycJ7Y+Y0IsJj6aDp9OxhRExyF+uocJR9 b9ChOH6PMEtRB/RRlBg66pbS61abvNGutzl61ZQZGBHEvL3VqDcd68IomdD5bNSB pXo6mOJIcKuXsghZszsHAV9uuMe4zQAMbLy7QH6V8LyWeSAG9hTXOT9EA4MWktEJ SCQFf7RRPgU5pEAgOS8LgKrawqnBaqFcFvkvWsQhyiltTFz29cwxH7tjSXYMAOFE W+RMp8kbkPnGOaJJeKxT+/RGRB534URk0jIEKtRb679xkEF3HE58exXEVrnojJq6 0m712+EYuZSYhFBwrvEnQjNHr0x2r/A/iBJZ6HhyV0aO1RWm4n4= =11pr -----END PGP SIGNATURE----- Merge tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux Pull xfs updates from Darrick Wong: "New features this cycle include the ability to relabel mounted filesystems, support for fallocated swapfiles, and using FUA for pure data O_DSYNC directio writes. With this cycle we begin to integrate online filesystem repair and refactor the growfs code in preparation for eventual subvolume support, though the road ahead for both features is quite long. There are also numerous refactorings of the iomap code to remove unnecessary log overhead, to disentangle some of the quota code, and to prepare for buffer head removal in a future upstream kernel. Metadata validation continues to improve, both in the hot path veifiers and the online filesystem check code. I anticipate sending a second pull request in a few days with more metadata validation improvements. This series has been run through a full xfstests run over the weekend and through a quick xfstests run against this morning's master, with no major failures reported. Summary: - Strengthen inode number and structure validation when allocating inodes. - Reduce pointless buffer allocations during cache miss - Use FUA for pure data O_DSYNC directio writes - Various iomap refactorings - Strengthen quota metadata verification to avoid unfixable broken quota - Make AGFL block freeing a deferred operation to avoid blowing out transaction reservations when running complex operations - Get rid of the log item descriptors to reduce log overhead - Fix various reflink bugs where inodes were double-joined to transactions - Don't issue discards when trimming unwritten extents - Refactor incore dquot initialization and retrieval interfaces - Fix some locking problmes in the quota scrub code - Strengthen btree structure checks in scrub code - Rewrite swapfile activation to use iomap and support unwritten extents - Make scrub exit to userspace sooner when corruptions or cross-referencing problems are found - Make scrub invoke the data fork scrubber directly on metadata inodes - Don't do background reclamation of post-eof and cow blocks when the fs is suspended - Fix secondary superblock buffer lifespan hinting - Refactor growfs to use table-dispatched functions instead of long stringy functions - Move growfs code to libxfs - Implement online fs label getting and setting - Introduce online filesystem repair (in a very limited capacity) - Fix unit conversion problems in the realtime freemap iteration functions - Various refactorings and cleanups in preparation to remove buffer heads in a future release - Reimplement the old bmap call with iomap - Remove direct buffer head accesses from seek hole/data - Various bug fixes" * tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (121 commits) fs: use ->is_partially_uptodate in page_cache_seek_hole_data fs: remove the buffer_unwritten check in page_seek_hole_data fs: move page_cache_seek_hole_data to iomap.c xfs: use iomap_bmap iomap: add an iomap-based bmap implementation iomap: add a iomap_sector helper iomap: use __bio_add_page in iomap_dio_zero iomap: move IOMAP_F_BOUNDARY to gfs2 iomap: fix the comment describing IOMAP_NOWAIT iomap: inline data should be an iomap type, not a flag mm: split ->readpages calls to avoid non-contiguous pages lists mm: return an unsigned int from __do_page_cache_readahead mm: give the 'ret' variable a better name __do_page_cache_readahead block: add a lower-level bio_add_page interface xfs: fix error handling in xfs_refcount_insert() xfs: fix xfs_rtalloc_rec units xfs: strengthen rtalloc query range checks xfs: xfs_rtbuf_get should check the bmapi_read results xfs: xfs_rtword_t should be unsigned, not signed dax: change bdev_dax_supported() to support boolean returns ... |
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Linus Torvalds
|
408afb8d78 |
Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull aio updates from Al Viro: "Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly. The only thing I'm holding back for a day or so is Adam's aio ioprio - his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case), but let it sit in -next for decency sake..." * 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) aio: sanitize the limit checking in io_submit(2) aio: fold do_io_submit() into callers aio: shift copyin of iocb into io_submit_one() aio_read_events_ring(): make a bit more readable aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way aio: take list removal to (some) callers of aio_complete() aio: add missing break for the IOCB_CMD_FDSYNC case random: convert to ->poll_mask timerfd: convert to ->poll_mask eventfd: switch to ->poll_mask pipe: convert to ->poll_mask crypto: af_alg: convert to ->poll_mask net/rxrpc: convert to ->poll_mask net/iucv: convert to ->poll_mask net/phonet: convert to ->poll_mask net/nfc: convert to ->poll_mask net/caif: convert to ->poll_mask net/bluetooth: convert to ->poll_mask net/sctp: convert to ->poll_mask net/tipc: convert to ->poll_mask ... |
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Linus Torvalds
|
eeee3149aa |
There's been a fair amount of work in the docs tree this time around,
including: - Extensive RST conversions and organizational work in the memory-management docs thanks to Mike Rapoport. - An update of Documentation/features from Andrea Parri and a script to keep it updated. - Various LICENSES updates from Thomas, along with a script to check SPDX tags. - Work to fix dangling references to documentation files; this involved a fair number of one-liner comment changes outside of Documentation/ ...and the usual list of documentation improvements, typo fixes, etc. -----BEGIN PGP SIGNATURE----- iQIcBAABAgAGBQJbFTkKAAoJEI3ONVYwIuV6t24P/0K9qltHkLwsBo2fbGu/emem mb1QrZCFZGebKVrCIvET3YcT0q0xPW+ZldwMQYEUeCcu/vD3cGHGXlDbVJCa1fFD 2OS10W/sEObPnREtlHO/zAzpapKP9DO1/f6NhO55iBJLGOCgoLL5xvSqgsI8MTGd vcJDXLitkh4CJEcfNLkQt8dEZzq9Tb6wdSFIvZBBXRNon2ItVN92D5xoQ0wtB+qt KmcGYofajK9bjtZpnC4iNg3i+zdwkd80bGTEN9f0hJTRZK5emCILk8fip8CMhRuB iwmcqb2RnMLydNLyK9RSs6OS5z3G4fYu9llRtLlZBAupcjRVpalWaBGxLOVO6jBG mvkqdKPMtxV4c7NvwKwFQL9dcjtxsxO4RDRYVWN82dS1L6WKKk8UvTuJUBLH0YA5 af7ZKn7mJVhJ1cxPblaEBOBM3oQuk57LLkjmcpMOXyJ/IOkTIuV1Ezht+XzFyFQv VWSyekiKo+8D6WHACPTaWiizjW15e8CyP+WIhKzJyn7VQQrZwhsOS+R//ITsuvQ0 vRdZ20lwUeBhR+mnXd5NfIo2w7G+OiqiREVAgxjgRrS0PnkzWG7lzzcSVU8HTfT4 S7VXqval2a9Xg+N8aU2JUe49W858J8hKvIa98hBxGoZa84wxOGtEo7pIKhnMwMSe Uhkh/1/bQMxsK3fBEF74 =I6FG -----END PGP SIGNATURE----- Merge tag 'docs-4.18' of git://git.lwn.net/linux Pull documentation updates from Jonathan Corbet: "There's been a fair amount of work in the docs tree this time around, including: - Extensive RST conversions and organizational work in the memory-management docs thanks to Mike Rapoport. - An update of Documentation/features from Andrea Parri and a script to keep it updated. - Various LICENSES updates from Thomas, along with a script to check SPDX tags. - Work to fix dangling references to documentation files; this involved a fair number of one-liner comment changes outside of Documentation/ ... and the usual list of documentation improvements, typo fixes, etc" * tag 'docs-4.18' of git://git.lwn.net/linux: (103 commits) Documentation: document hung_task_panic kernel parameter docs/admin-guide/mm: add high level concepts overview docs/vm: move ksm and transhuge from "user" to "internals" section. docs: Use the kerneldoc comments for memalloc_no*() doc: document scope NOFS, NOIO APIs docs: update kernel versions and dates in tables docs/vm: transhuge: split userspace bits to admin-guide/mm/transhuge docs/vm: transhuge: minor updates docs/vm: transhuge: change sections order Documentation: arm: clean up Marvell Berlin family info Documentation: gpio: driver: Fix a typo and some odd grammar docs: ranoops.rst: fix location of ramoops.txt scripts/documentation-file-ref-check: rewrite it in perl with auto-fix mode docs: uio-howto.rst: use a code block to solve a warning mm, THP, doc: Add document for thp_swpout/thp_swpout_fallback w1: w1_io.c: fix a kernel-doc warning Documentation/process/posting: wrap text at 80 cols docs: admin-guide: add cgroup-v2 documentation Revert "Documentation/features/vm: Remove arch support status file for 'pte_special'" Documentation: refcount-vs-atomic: Update reference to LKMM doc. ... |
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Linus Torvalds
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e5a594643a |
dma-mapping updates for 4.18:
- replaceme the force_dma flag with a dma_configure bus method. (Nipun Gupta, although one patch is іncorrectly attributed to me due to a git rebase bug) - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai) - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the right thing for bounce buffering. - move dma-debug initialization to common code, and apply a few cleanups to the dma-debug code. - cleanup the Kconfig mess around swiotlb selection - swiotlb comment fixup (Yisheng Xie) - a trivial swiotlb fix. (Dan Carpenter) - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt) - add a new generic dma-noncoherent dma_map_ops implementation and use it for arc, c6x and nds32. - improve scatterlist validity checking in dma-debug. (Robin Murphy) - add a struct device quirk to limit the dma-mask to 32-bit due to bridge/system issues, and switch x86 to use it instead of a local hack for VIA bridges. - handle devices without a dma_mask more gracefully in the dma-direct code. -----BEGIN PGP SIGNATURE----- iQI/BAABCAApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAlsU1hwLHGhjaEBsc3Qu ZGUACgkQD55TZVIEUYPraxAAocC7JiFKW133/VugCtGA1x9uE8DPHealtsWTAeEq KOOB3GxWMU2hKqQ4km5tcfdWoGJvvab6hmDXcitzZGi2JajO7Ae0FwIy3yvxSIKm iH/ON7c4sJt8gKrXYsLVylmwDaimNs4a6xfODoCRgnWuovI2QrrZzupnlzPNsiOC lv8ezzcW+Ay/gvDD/r72psO+w3QELETif/OzR/qTOtvLrVabM06eHmPQ8Wb98smu /UPMMv6/3XwQnxpxpdyqN+p/gUdneXithzT261wTeZ+8gDXmcWBwHGcMBCimcoBi FklW52moazIPIsTysqoNlVFsLGJTeS4p2D3BLAp5NwWYsLv+zHUVZsI1JY/8u5Ox mM11LIfvu9JtUzaqD9SvxlxIeLhhYZZGnUoV3bQAkpHSQhN/xp2YXd5NWSo5ac2O dch83+laZkZgd6ryw6USpt/YTPM/UHBYy7IeGGHX/PbmAke0ZlvA6Rae7kA5DG59 7GaLdwQyrHp8uGFgwze8P+R4POSk1ly73HHLBT/pFKnDD7niWCPAnBzuuEQGJs00 0zuyWLQyzOj1l6HCAcMNyGnYSsMp8Fx0fvEmKR/EYs8O83eJKXi6L9aizMZx4v1J 0wTolUWH6SIIdz474YmewhG5YOLY7mfe9E8aNr8zJFdwRZqwaALKoteRGUxa3f6e zUE= =6Acj -----END PGP SIGNATURE----- Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - replace the force_dma flag with a dma_configure bus method. (Nipun Gupta, although one patch is іncorrectly attributed to me due to a git rebase bug) - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai) - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the right thing for bounce buffering. - move dma-debug initialization to common code, and apply a few cleanups to the dma-debug code. - cleanup the Kconfig mess around swiotlb selection - swiotlb comment fixup (Yisheng Xie) - a trivial swiotlb fix. (Dan Carpenter) - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt) - add a new generic dma-noncoherent dma_map_ops implementation and use it for arc, c6x and nds32. - improve scatterlist validity checking in dma-debug. (Robin Murphy) - add a struct device quirk to limit the dma-mask to 32-bit due to bridge/system issues, and switch x86 to use it instead of a local hack for VIA bridges. - handle devices without a dma_mask more gracefully in the dma-direct code. * tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits) dma-direct: don't crash on device without dma_mask nds32: use generic dma_noncoherent_ops nds32: implement the unmap_sg DMA operation nds32: consolidate DMA cache maintainance routines x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag x86/pci-dma: remove the explicit nodac and allowdac option x86/pci-dma: remove the experimental forcesac boot option Documentation/x86: remove a stray reference to pci-nommu.c core, dma-direct: add a flag 32-bit dma limits dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs dma-debug: check scatterlist segments c6x: use generic dma_noncoherent_ops arc: use generic dma_noncoherent_ops arc: fix arc_dma_{map,unmap}_page arc: fix arc_dma_sync_sg_for_{cpu,device} arc: simplify arc_dma_sync_single_for_{cpu,device} dma-mapping: provide a generic dma-noncoherent implementation dma-mapping: simplify Kconfig dependencies riscv: add swiotlb support riscv: only enable ZONE_DMA32 for 64-bit ... |
||
Linus Torvalds
|
cf626b0da7 |
Merge branch 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull procfs updates from Al Viro: "Christoph's proc_create_... cleanups series" * 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (44 commits) xfs, proc: hide unused xfs procfs helpers isdn/gigaset: add back gigaset_procinfo assignment proc: update SIZEOF_PDE_INLINE_NAME for the new pde fields tty: replace ->proc_fops with ->proc_show ide: replace ->proc_fops with ->proc_show ide: remove ide_driver_proc_write isdn: replace ->proc_fops with ->proc_show atm: switch to proc_create_seq_private atm: simplify procfs code bluetooth: switch to proc_create_seq_data netfilter/x_tables: switch to proc_create_seq_private netfilter/xt_hashlimit: switch to proc_create_{seq,single}_data neigh: switch to proc_create_seq_data hostap: switch to proc_create_{seq,single}_data bonding: switch to proc_create_seq_data rtc/proc: switch to proc_create_single_data drbd: switch to proc_create_single resource: switch to proc_create_seq_data staging/rtl8192u: simplify procfs code jfs: simplify procfs code ... |
||
Linus Torvalds
|
f459c34538 |
for-4.18/block-20180603
-----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABCAAGBQJbFIrHAAoJEPfTWPspceCm2+kQAKo7o7HL30aRxJYu+gYafkuW PV47zr3e4vhMDEzDaMsh1+V7I7bm3uS+NZu6cFbcV+N9KXFpeb4V4Hvvm5cs+OC3 WCOBi4eC1h4qnDQ3ZyySrCMN+KHYJ16pZqddEjqw+fhVudx8i+F+jz3Y4ZMDDc3q pArKZvjKh2wEuYXUMFTjaXY46IgPt+er94OwvrhyHk+4AcA+Q/oqSfSdDahUC8jb BVR3FV4I3NOHUaru0RbrUko13sVZSboWPCIFrlTDz8xXcJOnVHzdVS1WLFDXLHnB O8q9cADCfa4K08kz68RxykcJiNxNvz5ChDaG0KloCFO+q1tzYRoXLsfaxyuUDg57 Zd93OFZC6hAzXdhclDFIuPET9OQIjDzwphodfKKmDsm3wtyOtydpA0o7JUEongp0 O1gQsEfYOXmQsXlo8Ot+Z7Ne/HvtGZ91JahUa/59edxQbcKaMrktoyQsQ/d1nOEL 4kXID18wPcFHWRQHYXyVuw6kbpRtQnh/U2m1eenSZ7tVQHwoe6mF3cfSf5MMseak k8nAnmsfEvOL4Ar9ftg61GOrImaQlidxOC2A8fmY5r0Sq/ZldvIFIZizsdTTCcni 8SOTxcQowyqPf5NvMNQ8cKqqCJap3ppj4m7anZNhbypDIF2TmOWsEcXcMDn4y9on fax14DPLo59gBRiPCn5f =nga/ -----END PGP SIGNATURE----- Merge tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block Pull block updates from Jens Axboe: - clean up how we pass around gfp_t and blk_mq_req_flags_t (Christoph) - prepare us to defer scheduler attach (Christoph) - clean up drivers handling of bounce buffers (Christoph) - fix timeout handling corner cases (Christoph/Bart/Keith) - bcache fixes (Coly) - prep work for bcachefs and some block layer optimizations (Kent). - convert users of bio_sets to using embedded structs (Kent). - fixes for the BFQ io scheduler (Paolo/Davide/Filippo) - lightnvm fixes and improvements (Matias, with contributions from Hans and Javier) - adding discard throttling to blk-wbt (me) - sbitmap blk-mq-tag handling (me/Omar/Ming). - remove the sparc jsflash block driver, acked by DaveM. - Kyber scheduler improvement from Jianchao, making it more friendly wrt merging. - conversion of symbolic proc permissions to octal, from Joe Perches. Previously the block parts were a mix of both. - nbd fixes (Josef and Kevin Vigor) - unify how we handle the various kinds of timestamps that the block core and utility code uses (Omar) - three NVMe pull requests from Keith and Christoph, bringing AEN to feature completeness, file backed namespaces, cq/sq lock split, and various fixes - various little fixes and improvements all over the map * tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block: (196 commits) blk-mq: update nr_requests when switching to 'none' scheduler block: don't use blocking queue entered for recursive bio submits dm-crypt: fix warning in shutdown path lightnvm: pblk: take bitmap alloc. out of critical section lightnvm: pblk: kick writer on new flush points lightnvm: pblk: only try to recover lines with written smeta lightnvm: pblk: remove unnecessary bio_get/put lightnvm: pblk: add possibility to set write buffer size manually lightnvm: fix partial read error path lightnvm: proper error handling for pblk_bio_add_pages lightnvm: pblk: fix smeta write error path lightnvm: pblk: garbage collect lines with failed writes lightnvm: pblk: rework write error recovery path lightnvm: pblk: remove dead function lightnvm: pass flag on graceful teardown to targets lightnvm: pblk: check for chunk size before allocating it lightnvm: pblk: remove unnecessary argument lightnvm: pblk: remove unnecessary indirection lightnvm: pblk: return NVM_ error on failed submission lightnvm: pblk: warn in case of corrupted write buffer ... |
||
Hugh Dickins
|
145e1a71e0 |
mm: fix the NULL mapping case in __isolate_lru_page()
George Boole would have noticed a slight error in 4.16 commit |
||
Hugh Dickins
|
2d077d4b59 |
mm/huge_memory.c: __split_huge_page() use atomic ClearPageDirty()
Swapping load on huge=always tmpfs (with khugepaged tuned up to be very eager, but I'm not sure that is relevant) soon hung uninterruptibly, waiting for page lock in shmem_getpage_gfp()'s find_lock_entry(), most often when "cp -a" was trying to write to a smallish file. Debug showed that the page in question was not locked, and page->mapping NULL by now, but page->index consistent with having been in a huge page before. Reproduced in minutes on a 4.15 kernel, even with 4.17's |
||
Christoph Hellwig
|
b3751e6ab4 |
mm: split ->readpages calls to avoid non-contiguous pages lists
That way file systems don't have to go spotting for non-contiguous pages and work around them. It also kicks off I/O earlier, allowing it to finish earlier and reduce latency. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> |
||
Christoph Hellwig
|
c534aa3fdd |
mm: return an unsigned int from __do_page_cache_readahead
We never return an error, so switch to returning an unsigned int. Most callers already did implicit casts to an unsigned type, and the one that didn't can be simplified now. Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> |
||
Christoph Hellwig
|
836978b35f |
mm: give the 'ret' variable a better name __do_page_cache_readahead
It counts the number of pages acted on, so name it nr_pages to make that obvious. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> |
||
Leon Romanovsky
|
27d036e332 |
mm: Remove return value of zap_vma_ptes()
All callers of zap_vma_ptes() are not interested in the return value of that function, so let's simplify its interface and drop the return value. Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com> |
||
Christoph Hellwig
|
9965ed174e |
fs: add new vfs_poll and file_can_poll helpers
These abstract out calls to the poll method in preparation for changes in how we poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> |
||
David Hildenbrand
|
3f19597215 |
kasan: fix memory hotplug during boot
Using module_init() is wrong. E.g. ACPI adds and onlines memory before
our memory notifier gets registered.
This makes sure that ACPI memory detected during boot up will not result
in a kernel crash.
Easily reproducible with QEMU, just specify a DIMM when starting up.
Link: http://lkml.kernel.org/r/20180522100756.18478-3-david@redhat.com
Fixes:
|
||
David Hildenbrand
|
ed1596f9ab |
kasan: free allocated shadow memory on MEM_CANCEL_ONLINE
We have to free memory again when we cancel onlining, otherwise a later
onlining attempt will fail.
Link: http://lkml.kernel.org/r/20180522100756.18478-2-david@redhat.com
Fixes:
|
||
Jonathan Cameron
|
a21558618c |
mm/memory_hotplug: fix leftover use of struct page during hotplug
The case of a new numa node got missed in avoiding using the node info
from page_struct during hotplug. In this path we have a call to
register_mem_sect_under_node (which allows us to specify it is hotplug
so don't change the node), via link_mem_sections which unfortunately
does not.
Fix is to pass check_nid through link_mem_sections as well and disable
it in the new numa node path.
Note the bug only 'sometimes' manifests depending on what happens to be
in the struct page structures - there are lots of them and it only needs
to match one of them.
The result of the bug is that (with a new memory only node) we never
successfully call register_mem_sect_under_node so don't get the memory
associated with the node in sysfs and meminfo for the node doesn't
report it.
It came up whilst testing some arm64 hotplug patches, but appears to be
universal. Whilst I'm triggering it by removing then reinserting memory
to a node with no other elements (thus making the node disappear then
appear again), it appears it would happen on hotplugging memory where
there was none before and it doesn't seem to be related the arm64
patches.
These patches call __add_pages (where most of the issue was fixed by
Pavel's patch). If there is a node at the time of the __add_pages call
then all is well as it calls register_mem_sect_under_node from there
with check_nid set to false. Without a node that function returns
having not done the sysfs related stuff as there is no node to use.
This is expected but it is the resulting path that fails...
Exact path to the problem is as follows:
mm/memory_hotplug.c: add_memory_resource()
The node is not online so we enter the 'if (new_node)' twice, on the
second such block there is a call to link_mem_sections which calls
into
drivers/node.c: link_mem_sections() which calls
drivers/node.c: register_mem_sect_under_node() which calls
get_nid_for_pfn and keeps trying until the output of that matches
the expected node (passed all the way down from
add_memory_resource)
It is effectively the same fix as the one referred to in the fixes tag
just in the code path for a new node where the comments point out we
have to rerun the link creation because it will have failed in
register_new_memory (as there was no node at the time). (actually that
comment is wrong now as we don't have register_new_memory any more it
got renamed to hotplug_memory_register in Pavel's patch).
Link: http://lkml.kernel.org/r/20180504085311.1240-1-Jonathan.Cameron@huawei.com
Fixes:
|
||
Michal Hocko
|
15c30bc090 |
mm, memory_hotplug: make has_unmovable_pages more robust
Oscar has reported:
: Due to an unfortunate setting with movablecore, memblocks containing bootmem
: memory (pages marked by get_page_bootmem()) ended up marked in zone_movable.
: So while trying to remove that memory, the system failed in do_migrate_range
: and __offline_pages never returned.
:
: This can be reproduced by running
: qemu-system-x86_64 -m 6G,slots=8,maxmem=8G -numa node,mem=4096M -numa node,mem=2048M
: and movablecore=4G kernel command line
:
: linux kernel: BIOS-provided physical RAM map:
: linux kernel: BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
: linux kernel: BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
: linux kernel: BIOS-e820: [mem 0x0000000000100000-0x00000000bffdffff] usable
: linux kernel: BIOS-e820: [mem 0x00000000bffe0000-0x00000000bfffffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
: linux kernel: BIOS-e820: [mem 0x0000000100000000-0x00000001bfffffff] usable
: linux kernel: NX (Execute Disable) protection: active
: linux kernel: SMBIOS 2.8 present.
: linux kernel: DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org
: linux kernel: Hypervisor detected: KVM
: linux kernel: e820: update [mem 0x00000000-0x00000fff] usable ==> reserved
: linux kernel: e820: remove [mem 0x000a0000-0x000fffff] usable
: linux kernel: last_pfn = 0x1c0000 max_arch_pfn = 0x400000000
:
: linux kernel: SRAT: PXM 0 -> APIC 0x00 -> Node 0
: linux kernel: SRAT: PXM 1 -> APIC 0x01 -> Node 1
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00000000-0x0009ffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00100000-0xbfffffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0x13fffffff]
: linux kernel: ACPI: SRAT: Node 1 PXM 1 [mem 0x140000000-0x1bfffffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x1c0000000-0x43fffffff] hotplug
: linux kernel: NUMA: Node 0 [mem 0x00000000-0x0009ffff] + [mem 0x00100000-0xbfffffff] -> [mem 0x0
: linux kernel: NUMA: Node 0 [mem 0x00000000-0xbfffffff] + [mem 0x100000000-0x13fffffff] -> [mem 0
: linux kernel: NODE_DATA(0) allocated [mem 0x13ffd6000-0x13fffffff]
: linux kernel: NODE_DATA(1) allocated [mem 0x1bffd3000-0x1bfffcfff]
:
: zoneinfo shows that the zone movable is placed into both numa nodes:
: Node 0, zone Movable
: pages free 160140
: min 1823
: low 2278
: high 2733
: spanned 262144
: present 262144
: managed 245670
: Node 1, zone Movable
: pages free 448427
: min 3827
: low 4783
: high 5739
: spanned 524288
: present 524288
: managed 515766
Note how only Node 0 has a hutplugable memory region which would rule it
out from the early memblock allocations (most likely memmap). Node1
will surely contain memmaps on the same node and those would prevent
offlining to succeed. So this is arguably a configuration issue.
Although one could argue that we should be more clever and rule early
allocations from the zone movable. This would be correct but probably
not worth the effort considering what a hack movablecore is.
Anyway, We could do better for those cases though. We rely on
start_isolate_page_range resp. has_unmovable_pages to do their job.
The first one isolates the whole range to be offlined so that we do not
allocate from it anymore and the later makes sure we are not stumbling
over non-migrateable pages.
has_unmovable_pages is overly optimistic, however. It doesn't check all
the pages if we are withing zone_movable because we rely that those
pages will be always migrateable. As it turns out we are still not
perfect there. While bootmem pages in zonemovable sound like a clear
bug which should be fixed let's remove the optimization for now and warn
if we encounter unmovable pages in zone_movable in the meantime. That
should help for now at least.
Btw. this wasn't a real problem until commit
|
||
Andrey Ryabinin
|
0f901dcbc3 |
mm/kasan: don't vfree() nonexistent vm_area
KASAN uses different routines to map shadow for hot added memory and
memory obtained in boot process. Attempt to offline memory onlined by
normal boot process leads to this:
Trying to vfree() nonexistent vm area (000000005d3b34b9)
WARNING: CPU: 2 PID: 13215 at mm/vmalloc.c:1525 __vunmap+0x147/0x190
Call Trace:
kasan_mem_notifier+0xad/0xb9
notifier_call_chain+0x166/0x260
__blocking_notifier_call_chain+0xdb/0x140
__offline_pages+0x96a/0xb10
memory_subsys_offline+0x76/0xc0
device_offline+0xb8/0x120
store_mem_state+0xfa/0x120
kernfs_fop_write+0x1d5/0x320
__vfs_write+0xd4/0x530
vfs_write+0x105/0x340
SyS_write+0xb0/0x140
Obviously we can't call vfree() to free memory that wasn't allocated via
vmalloc(). Use find_vm_area() to see if we can call vfree().
Unfortunately it's a bit tricky to properly unmap and free shadow
allocated during boot, so we'll have to keep it. If memory will come
online again that shadow will be reused.
Matthew asked: how can you call vfree() on something that isn't a
vmalloc address?
vfree() is able to free any address returned by
__vmalloc_node_range(). And __vmalloc_node_range() gives you any
address you ask. It doesn't have to be an address in [VMALLOC_START,
VMALLOC_END] range.
That's also how the module_alloc()/module_memfree() works on
architectures that have designated area for modules.
[aryabinin@virtuozzo.com: improve comments]
Link: http://lkml.kernel.org/r/dabee6ab-3a7a-51cd-3b86-5468718e0390@virtuozzo.com
[akpm@linux-foundation.org: fix typos, reflow comment]
Link: http://lkml.kernel.org/r/20180201163349.8700-1-aryabinin@virtuozzo.com
Fixes:
|
||
Omar Sandoval
|
7cbf319234 |
mm: fix nr_rotate_swap leak in swapon() error case
If swapon() fails after incrementing nr_rotate_swap, we don't decrement
it and thus effectively leak it. Make sure we decrement it if we
incremented it.
Link: http://lkml.kernel.org/r/b6fe6b879f17fa68eee6cbd876f459f6e5e33495.1526491581.git.osandov@fb.com
Fixes:
|
||
Joonsoo Kim
|
d883c6cf3b |
Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE"
This reverts the following commits that change CMA design in MM. |
||
Tejun Heo
|
f183464684 |
bdi: Move cgroup bdi_writeback to a dedicated low concurrency workqueue
From 0aa2e9b921d6db71150633ff290199554f0842a8 Mon Sep 17 00:00:00 2001 From: Tejun Heo <tj@kernel.org> Date: Wed, 23 May 2018 10:29:00 -0700 cgwb_release() punts the actual release to cgwb_release_workfn() on system_wq. Depending on the number of cgroups or block devices, there can be a lot of cgwb_release_workfn() in flight at the same time. We're periodically seeing close to 256 kworkers getting stuck with the following stack trace and overtime the entire system gets stuck. [<ffffffff810ee40c>] _synchronize_rcu_expedited.constprop.72+0x2fc/0x330 [<ffffffff810ee634>] synchronize_rcu_expedited+0x24/0x30 [<ffffffff811ccf23>] bdi_unregister+0x53/0x290 [<ffffffff811cd1e9>] release_bdi+0x89/0xc0 [<ffffffff811cd645>] wb_exit+0x85/0xa0 [<ffffffff811cdc84>] cgwb_release_workfn+0x54/0xb0 [<ffffffff810a68d0>] process_one_work+0x150/0x410 [<ffffffff810a71fd>] worker_thread+0x6d/0x520 [<ffffffff810ad3dc>] kthread+0x12c/0x160 [<ffffffff81969019>] ret_from_fork+0x29/0x40 [<ffffffffffffffff>] 0xffffffffffffffff The events leading to the lockup are... 1. A lot of cgwb_release_workfn() is queued at the same time and all system_wq kworkers are assigned to execute them. 2. They all end up calling synchronize_rcu_expedited(). One of them wins and tries to perform the expedited synchronization. 3. However, that invovles queueing rcu_exp_work to system_wq and waiting for it. Because #1 is holding all available kworkers on system_wq, rcu_exp_work can't be executed. cgwb_release_workfn() is waiting for synchronize_rcu_expedited() which in turn is waiting for cgwb_release_workfn() to free up some of the kworkers. We shouldn't be scheduling hundreds of cgwb_release_workfn() at the same time. There's nothing to be gained from that. This patch updates cgwb release path to use a dedicated percpu workqueue with @max_active of 1. While this resolves the problem at hand, it might be a good idea to isolate rcu_exp_work to its own workqueue too as it can be used from various paths and is prone to this sort of indirect A-A deadlocks. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
Dan Williams
|
a9b6de77b1 |
mm: fix __gup_device_huge vs unmap
get_user_pages_fast() for device pages is missing the typical validation
that all page references have been taken while the mapping was valid.
Without this validation truncate operations can not reliably coordinate
against new page reference events like O_DIRECT.
Cc: <stable@vger.kernel.org>
Fixes:
|
||
Dan Williams
|
e763848843 |
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
In preparation for fixing dax-dma-vs-unmap issues, filesystems need to be able to rely on the fact that they will get wakeups on dev_pagemap page-idle events. Introduce MEMORY_DEVICE_FS_DAX and generic_dax_page_free() as common indicator / infrastructure for dax filesytems to require. With this change there are no users of the MEMORY_DEVICE_HOST designation, so remove it. The HMM sub-system extended dev_pagemap to arrange a callback when a dev_pagemap managed page is freed. Since a dev_pagemap page is free / idle when its reference count is 1 it requires an additional branch to check the page-type at put_page() time. Given put_page() is a hot-path we do not want to incur that check if HMM is not in use, so a static branch is used to avoid that overhead when not necessary. Now, the FS_DAX implementation wants to reuse this mechanism for receiving dev_pagemap ->page_free() callbacks. Rework the HMM-specific static-key into a generic mechanism that either HMM or FS_DAX code paths can enable. For ARCH=um builds, and any other arch that lacks ZONE_DEVICE support, care must be taken to compile out the DEV_PAGEMAP_OPS infrastructure. However, we still need to support FS_DAX in the FS_DAX_LIMITED case implemented by the s390/dcssblk driver. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Thomas Meyer <thomas@m3y3r.de> Reported-by: Dave Jiang <dave.jiang@intel.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
Linus Torvalds
|
423913ad4a |
mmap: relax file size limit for regular files
Commit |
||
Pavel Tatashin
|
ab1e8d8960 |
mm: don't allow deferred pages with NEED_PER_CPU_KM
It is unsafe to do virtual to physical translations before mm_init() is called if struct page is needed in order to determine the memory section number (see SECTION_IN_PAGE_FLAGS). This is because only in mm_init() we initialize struct pages for all the allocated memory when deferred struct pages are used. My recent fix in commit |
||
Willy Tarreau
|
7f7ccc2ccc |
proc: do not access cmdline nor environ from file-backed areas
proc_pid_cmdline_read() and environ_read() directly access the target process' VM to retrieve the command line and environment. If this process remaps these areas onto a file via mmap(), the requesting process may experience various issues such as extra delays if the underlying device is slow to respond. Let's simply refuse to access file-backed areas in these functions. For this we add a new FOLL_ANON gup flag that is passed to all calls to access_remote_vm(). The code already takes care of such failures (including unmapped areas). Accesses via /proc/pid/mem were not changed though. This was assigned CVE-2018-1120. Note for stable backports: the patch may apply to kernels prior to 4.11 but silently miss one location; it must be checked that no call to access_remote_vm() keeps zero as the last argument. Reported-by: Qualys Security Advisory <qsa@qualys.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Christoph Hellwig
|
44414d82cf |
proc: introduce proc_create_seq_private
Variant of proc_create_data that directly take a struct seq_operations argument + a private state size and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de> |
||
Christoph Hellwig
|
fddda2b7b5 |
proc: introduce proc_create_seq{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations argument and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de> |
||
Kent Overstreet
|
c1a67fefd0 |
mempool: Add mempool_init()/mempool_exit()
Allows mempools to be embedded in other structs, getting rid of a pointer indirection from allocation fastpaths. mempool_exit() is safe to call on an uninitialized but zeroed mempool. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
Linus Torvalds
|
f0ab773f5c |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton: "13 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: rbtree: include rcu.h scripts/faddr2line: fix error when addr2line output contains discriminator ocfs2: take inode cluster lock before moving reflinked inode from orphan dir mm, oom: fix concurrent munlock and oom reaper unmap, v3 mm: migrate: fix double call of radix_tree_replace_slot() proc/kcore: don't bounds check against address 0 mm: don't show nr_indirectly_reclaimable in /proc/vmstat mm: sections are not offlined during memory hotremove z3fold: fix reclaim lock-ups init: fix false positives in W+X checking lib/find_bit_benchmark.c: avoid soft lockup in test_find_first_bit() KASAN: prohibit KASAN+STRUCTLEAK combination MAINTAINERS: update Shuah's email address |
||
David Rientjes
|
27ae357fa8 |
mm, oom: fix concurrent munlock and oom reaper unmap, v3
Since exit_mmap() is done without the protection of mm->mmap_sem, it is
possible for the oom reaper to concurrently operate on an mm until
MMF_OOM_SKIP is set.
This allows munlock_vma_pages_all() to concurrently run while the oom
reaper is operating on a vma. Since munlock_vma_pages_range() depends
on clearing VM_LOCKED from vm_flags before actually doing the munlock to
determine if any other vmas are locking the same memory, the check for
VM_LOCKED in the oom reaper is racy.
This is especially noticeable on architectures such as powerpc where
clearing a huge pmd requires serialize_against_pte_lookup(). If the pmd
is zapped by the oom reaper during follow_page_mask() after the check
for pmd_none() is bypassed, this ends up deferencing a NULL ptl or a
kernel oops.
Fix this by manually freeing all possible memory from the mm before
doing the munlock and then setting MMF_OOM_SKIP. The oom reaper can not
run on the mm anymore so the munlock is safe to do in exit_mmap(). It
also matches the logic that the oom reaper currently uses for
determining when to set MMF_OOM_SKIP itself, so there's no new risk of
excessive oom killing.
This issue fixes CVE-2018-1000200.
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1804241526320.238665@chino.kir.corp.google.com
Fixes:
|
||
Naoya Horiguchi
|
013567be19 |
mm: migrate: fix double call of radix_tree_replace_slot()
radix_tree_replace_slot() is called twice for head page, it's obviously
a bug. Let's fix it.
Link: http://lkml.kernel.org/r/20180423072101.GA12157@hori1.linux.bs1.fc.nec.co.jp
Fixes:
|
||
Roman Gushchin
|
7aaf772723 |
mm: don't show nr_indirectly_reclaimable in /proc/vmstat
Don't show nr_indirectly_reclaimable in /proc/vmstat, because there is no need to export this vm counter to userspace, and some changes are expected in reclaimable object accounting, which can alter this counter. Link: http://lkml.kernel.org/r/20180425191422.9159-1-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Pavel Tatashin
|
27227c7338 |
mm: sections are not offlined during memory hotremove
Memory hotplug and hotremove operate with per-block granularity. If the
machine has a large amount of memory (more than 64G), the size of a
memory block can span multiple sections. By mistake, during hotremove
we set only the first section to offline state.
The bug was discovered because kernel selftest started to fail:
https://lkml.kernel.org/r/20180423011247.GK5563@yexl-desktop
After commit, "mm/memory_hotplug: optimize probe routine". But, the bug
is older than this commit. In this optimization we also added a check
for sections to be in a proper state during hotplug operation.
Link: http://lkml.kernel.org/r/20180427145257.15222-1-pasha.tatashin@oracle.com
Fixes:
|
||
Vitaly Wool
|
6098d7e136 |
z3fold: fix reclaim lock-ups
Do not try to optimize in-page object layout while the page is under reclaim. This fixes lock-ups on reclaim and improves reclaim performance at the same time. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20180430125800.444cae9706489f412ad12621@gmail.com Signed-off-by: Vitaly Wool <vitaly.vul@sony.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: <Oleksiy.Avramchenko@sony.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Linus Torvalds
|
be83bbf806 |
mmap: introduce sane default mmap limits
The internal VM "mmap()" interfaces are based on the mmap target doing everything using page indexes rather than byte offsets, because traditionally (ie 32-bit) we had the situation that the byte offset didn't fit in a register. So while the mmap virtual address was limited by the word size of the architecture, the backing store was not. So we're basically passing "pgoff" around as a page index, in order to be able to describe backing store locations that are much bigger than the word size (think files larger than 4GB etc). But while this all makes a ton of sense conceptually, we've been dogged by various drivers that don't really understand this, and internally work with byte offsets, and then try to work with the page index by turning it into a byte offset with "pgoff << PAGE_SHIFT". Which obviously can overflow. Adding the size of the mapping to it to get the byte offset of the end of the backing store just exacerbates the problem, and if you then use this overflow-prone value to check various limits of your device driver mmap capability, you're just setting yourself up for problems. The correct thing for drivers to do is to do their limit math in page indices, the way the interface is designed. Because the generic mmap code _does_ test that the index doesn't overflow, since that's what the mmap code really cares about. HOWEVER. Finding and fixing various random drivers is a sisyphean task, so let's just see if we can just make the core mmap() code do the limiting for us. Realistically, the only "big" backing stores we need to care about are regular files and block devices, both of which are known to do this properly, and which have nice well-defined limits for how much data they can access. So let's special-case just those two known cases, and then limit other random mmap users to a backing store that still fits in "unsigned long". Realistically, that's not much of a limit at all on 64-bit, and on 32-bit architectures the only worry might be the GPU drivers, which can have big physical address spaces. To make it possible for drivers like that to say that they are 64-bit clean, this patch does repurpose the "FMODE_UNSIGNED_OFFSET" bit in the file flags to allow drivers to mark their file descriptors as safe in the full 64-bit mmap address space. [ The timing for doing this is less than optimal, and this should really go in a merge window. But realistically, this needs wide testing more than it needs anything else, and being main-line is the only way to do that. So the earlier the better, even if it's outside the proper development cycle - Linus ] Cc: Kees Cook <keescook@chromium.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Willy Tarreau <w@1wt.eu> Cc: Dave Airlie <airlied@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Christoph Hellwig
|
d4a451d5fc |
arch: remove the ARCH_PHYS_ADDR_T_64BIT config symbol
Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a 64-bit phys_addr_t type directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: James Hogan <jhogan@kernel.org> |
||
Linus Torvalds
|
2f50037a1c |
for-linus-20180504
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||
Tetsuo Handa
|
f53823c181 |
bdi: Fix use after free bug in debugfs_remove()
syzbot is reporting use after free bug in debugfs_remove() [1].
This is because fault injection made memory allocation for
debugfs_create_file() from bdi_debug_register() from bdi_register_va()
fail and continued with setting WB_registered. But when debugfs_remove()
is called from debugfs_remove(bdi->debug_dir) from bdi_debug_unregister()
from bdi_unregister() from release_bdi() because WB_registered was set
by bdi_register_va(), IS_ERR_OR_NULL(bdi->debug_dir) == false despite
debugfs_remove(bdi->debug_dir) was already called from bdi_register_va().
Fix this by making IS_ERR_OR_NULL(bdi->debug_dir) == true.
[1] https://syzkaller.appspot.com/bug?id=5ab4efd91a96dcea9b68104f159adf4af2a6dfc1
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+049cb4ae097049dac137@syzkaller.appspotmail.com>
Fixes:
|
||
Tetsuo Handa
|
8236b0ae31 |
bdi: wake up concurrent wb_shutdown() callers.
syzbot is reporting hung tasks at wait_on_bit(WB_shutting_down) in wb_shutdown() [1]. This seems to be because commit |
||
Mike Rapoport
|
5a2ca3efe6 |
mm/ksm: docs: extend overview comment and make it "DOC:"
The existing comment provides a good overview of KSM implementation. Let's update it to reflect recent additions of "chain" and "dup" variants of the stable tree nodes and mark it as "DOC:" for inclusion into the KSM documentation. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
||
Jonathan Corbet
|
ccf2b06794 |
Linux 4.17-rc2
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlrdQu4eHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGVjEIAJqS+sFJCAL8rNAv tiVJHuAjogVdZGJJFBUWyb4yNZw7nRSKfitaSe875WdF55IGEhnMDbAGe7IMEb5j 1F8Ml2bzJzMWxfBWAzeU+wj6FaQksbIsI1gVM8tqk/Wtu121pB32VW8R82oHg+Hr sjsFTKFicNsqih+7QTVujaRjSmabKf0/JdyYM6p1cqWrxZQ0pmFaGDu0rwet9PFx lJsewOmnoZ0GV/Qzn40E304Xf+Vv2gVDVbC5wY86ejNigFt+5qN+gtDqDu7UkftR ZfD4vJuiKCigNfUrpbJWfpbegBiQc0JMvjLWWhgo/AYdGhNGMlwjQanh2oZcXlrw VmrNduo= =/j3z -----END PGP SIGNATURE----- Merge tag 'v4.17-rc2' into docs-next Merge -rc2 to pick up the changes to Documentation/core-api/kernel-api.rst that hit mainline via the networking tree. In their absence, subsequent patches cannot be applied. |
||
Mike Rapoport
|
1ad1335dc5 |
docs/admin-guide/mm: start moving here files from Documentation/vm
Several documents in Documentation/vm fit quite well into the "admin/user guide" category. The documents that don't overload the reader with lots of implementation details and provide coherent description of certain feature can be moved to Documentation/admin-guide/mm. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
||
Dave Hansen
|
316d097c4c |
x86/pti: Filter at vma->vm_page_prot population
commit ce9962bf7e22bb3891655c349faff618922d4a73
0day reported warnings at boot on 32-bit systems without NX support:
attempted to set unsupported pgprot: 8000000000000025 bits: 8000000000000000 supported: 7fffffffffffffff
WARNING: CPU: 0 PID: 1 at
arch/x86/include/asm/pgtable.h:540 handle_mm_fault+0xfc1/0xfe0:
check_pgprot at arch/x86/include/asm/pgtable.h:535
(inlined by) pfn_pte at arch/x86/include/asm/pgtable.h:549
(inlined by) do_anonymous_page at mm/memory.c:3169
(inlined by) handle_pte_fault at mm/memory.c:3961
(inlined by) __handle_mm_fault at mm/memory.c:4087
(inlined by) handle_mm_fault at mm/memory.c:4124
The problem is that due to the recent commit which removed auto-massaging
of page protections, filtering page permissions at PTE creation time is not
longer done, so vma->vm_page_prot is passed unfiltered to PTE creation.
Filter the page protections before they are installed in vma->vm_page_prot.
Fixes:
|
||
Matthew Wilcox
|
abc1be13fd |
mm/filemap.c: fix NULL pointer in page_cache_tree_insert()
f2fs specifies the __GFP_ZERO flag for allocating some of its pages.
Unfortunately, the page cache also uses the mapping's GFP flags for
allocating radix tree nodes. It always masked off the __GFP_HIGHMEM
flag, and masks off __GFP_ZERO in some paths, but not all. That causes
radix tree nodes to be allocated with a NULL list_head, which causes
backtraces like:
__list_del_entry+0x30/0xd0
list_lru_del+0xac/0x1ac
page_cache_tree_insert+0xd8/0x110
The __GFP_DMA and __GFP_DMA32 flags would also be able to sneak through
if they are ever used. Fix them all by using GFP_RECLAIM_MASK at the
innermost location, and remove it from earlier in the callchain.
Link: http://lkml.kernel.org/r/20180411060320.14458-2-willy@infradead.org
Fixes:
|
||
Minchan Kim
|
c892fd82cc |
mm: memcg: add __GFP_NOWARN in __memcg_schedule_kmem_cache_create()
If there is heavy memory pressure, page allocation with __GFP_NOWAIT fails easily although it's order-0 request. I got below warning 9 times for normal boot. <snip >: page allocation failure: order:0, mode:0x2200000(GFP_NOWAIT|__GFP_NOTRACK) .. snip .. Call trace: dump_backtrace+0x0/0x4 dump_stack+0xa4/0xc0 warn_alloc+0xd4/0x15c __alloc_pages_nodemask+0xf88/0x10fc alloc_slab_page+0x40/0x18c new_slab+0x2b8/0x2e0 ___slab_alloc+0x25c/0x464 __kmalloc+0x394/0x498 memcg_kmem_get_cache+0x114/0x2b8 kmem_cache_alloc+0x98/0x3e8 mmap_region+0x3bc/0x8c0 do_mmap+0x40c/0x43c vm_mmap_pgoff+0x15c/0x1e4 sys_mmap+0xb0/0xc8 el0_svc_naked+0x24/0x28 Mem-Info: active_anon:17124 inactive_anon:193 isolated_anon:0 active_file:7898 inactive_file:712955 isolated_file:55 unevictable:0 dirty:27 writeback:18 unstable:0 slab_reclaimable:12250 slab_unreclaimable:23334 mapped:19310 shmem:212 pagetables:816 bounce:0 free:36561 free_pcp:1205 free_cma:35615 Node 0 active_anon:68496kB inactive_anon:772kB active_file:31592kB inactive_file:2851820kB unevictable:0kB isolated(anon):0kB isolated(file):220kB mapped:77240kB dirty:108kB writeback:72kB shmem:848kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no DMA free:142188kB min:3056kB low:3820kB high:4584kB active_anon:10052kB inactive_anon:12kB active_file:312kB inactive_file:1412620kB unevictable:0kB writepending:0kB present:1781412kB managed:1604728kB mlocked:0kB slab_reclaimable:3592kB slab_unreclaimable:876kB kernel_stack:400kB pagetables:52kB bounce:0kB free_pcp:1436kB local_pcp:124kB free_cma:142492kB lowmem_reserve[]: 0 1842 1842 Normal free:4056kB min:4172kB low:5212kB high:6252kB active_anon:58376kB inactive_anon:760kB active_file:31348kB inactive_file:1439040kB unevictable:0kB writepending:180kB present:2000636kB managed:1923688kB mlocked:0kB slab_reclaimable:45408kB slab_unreclaimable:92460kB kernel_stack:9680kB pagetables:3212kB bounce:0kB free_pcp:3392kB local_pcp:688kB free_cma:0kB lowmem_reserve[]: 0 0 0 DMA: 0*4kB 0*8kB 1*16kB (C) 0*32kB 0*64kB 0*128kB 1*256kB (C) 1*512kB (C) 0*1024kB 1*2048kB (C) 34*4096kB (C) = 142096kB Normal: 228*4kB (UMEH) 172*8kB (UMH) 23*16kB (UH) 24*32kB (H) 5*64kB (H) 1*128kB (H) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3872kB 721350 total pagecache pages 0 pages in swap cache Swap cache stats: add 0, delete 0, find 0/0 Free swap = 0kB Total swap = 0kB 945512 pages RAM 0 pages HighMem/MovableOnly 63408 pages reserved 51200 pages cma reserved __memcg_schedule_kmem_cache_create() tries to create a shadow slab cache and the worker allocation failure is not really critical because we will retry on the next kmem charge. We might miss some charges but that shouldn't be critical. The excessive allocation failure report is not very helpful. [mhocko@kernel.org: changelog update] Link: http://lkml.kernel.org/r/20180418022912.248417-1-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Naoya Horiguchi
|
e71769ae52 |
mm: enable thp migration for shmem thp
My testing for the latest kernel supporting thp migration showed an
infinite loop in offlining the memory block that is filled with shmem
thps. We can get out of the loop with a signal, but kernel should return
with failure in this case.
What happens in the loop is that scan_movable_pages() repeats returning
the same pfn without any progress. That's because page migration always
fails for shmem thps.
In memory offline code, memory blocks containing unmovable pages should be
prevented from being offline targets by has_unmovable_pages() inside
start_isolate_page_range(). So it's possible to change migratability for
non-anonymous thps to avoid the issue, but it introduces more complex and
thp-specific handling in migration code, so it might not good.
So this patch is suggesting to fix the issue by enabling thp migration for
shmem thp. Both of anon/shmem thp are migratable so we don't need
precheck about the type of thps.
Link: http://lkml.kernel.org/r/20180406030706.GA2434@hori1.linux.bs1.fc.nec.co.jp
Fixes: commit
|
||
Greg Thelen
|
2e898e4c0a |
writeback: safer lock nesting
lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if
the page's memcg is undergoing move accounting, which occurs when a
process leaves its memcg for a new one that has
memory.move_charge_at_immigrate set.
unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if
the given inode is switching writeback domains. Switches occur when
enough writes are issued from a new domain.
This existing pattern is thus suspicious:
lock_page_memcg(page);
unlocked_inode_to_wb_begin(inode, &locked);
...
unlocked_inode_to_wb_end(inode, locked);
unlock_page_memcg(page);
If both inode switch and process memcg migration are both in-flight then
unlocked_inode_to_wb_end() will unconditionally enable interrupts while
still holding the lock_page_memcg() irq spinlock. This suggests the
possibility of deadlock if an interrupt occurs before unlock_page_memcg().
truncate
__cancel_dirty_page
lock_page_memcg
unlocked_inode_to_wb_begin
unlocked_inode_to_wb_end
<interrupts mistakenly enabled>
<interrupt>
end_page_writeback
test_clear_page_writeback
lock_page_memcg
<deadlock>
unlock_page_memcg
Due to configuration limitations this deadlock is not currently possible
because we don't mix cgroup writeback (a cgroupv2 feature) and
memory.move_charge_at_immigrate (a cgroupv1 feature).
If the kernel is hacked to always claim inode switching and memcg
moving_account, then this script triggers lockup in less than a minute:
cd /mnt/cgroup/memory
mkdir a b
echo 1 > a/memory.move_charge_at_immigrate
echo 1 > b/memory.move_charge_at_immigrate
(
echo $BASHPID > a/cgroup.procs
while true; do
dd if=/dev/zero of=/mnt/big bs=1M count=256
done
) &
while true; do
sync
done &
sleep 1h &
SLEEP=$!
while true; do
echo $SLEEP > a/cgroup.procs
echo $SLEEP > b/cgroup.procs
done
The deadlock does not seem possible, so it's debatable if there's any
reason to modify the kernel. I suggest we should to prevent future
surprises. And Wang Long said "this deadlock occurs three times in our
environment", so there's more reason to apply this, even to stable.
Stable 4.4 has minor conflicts applying this patch. For a clean 4.4 patch
see "[PATCH for-4.4] writeback: safer lock nesting"
https://lkml.org/lkml/2018/4/11/146
Wang Long said "this deadlock occurs three times in our environment"
[gthelen@google.com: v4]
Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com
[akpm@linux-foundation.org: comment tweaks, struct initialization simplification]
Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613
Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com
Fixes:
|
||
Michal Hocko
|
8f175cf5c9 |
mm: fix do_pages_move status handling
Li Wang has reported that LTP move_pages04 test fails with the current tree: LTP move_pages04: TFAIL : move_pages04.c:143: status[1] is EPERM, expected EFAULT The test allocates an array of two pages, one is present while the other is not (resp. backed by zero page) and it expects EFAULT for the second page as the man page suggests. We are reporting EPERM which doesn't make any sense and this is a result of a bug from cf5f16b23ec9 ("mm: unclutter THP migration"). do_pages_move tries to handle as many pages in one batch as possible so we queue all pages with the same node target together and that corresponds to [start, i] range which is then used to update status array. add_page_for_migration will correctly notice the zero (resp. !present) page and returns with EFAULT which gets written to the status. But if this is the last page in the array we do not update start and so the last store_status after the loop will overwrite the range of the last batch with NUMA_NO_NODE (which corresponds to EPERM). Fix this by simply bailing out from the last flush if the pagelist is empty as there is clearly nothing more to do. Link: http://lkml.kernel.org/r/20180418121255.334-1-mhocko@kernel.org Fixes: cf5f16b23ec9 ("mm: unclutter THP migration") Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Li Wang <liwang@redhat.com> Tested-by: Li Wang <liwang@redhat.com> Cc: Zi Yan <zi.yan@cs.rutgers.edu> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Jonathan Corbet
|
24844fd339 |
Merge branch 'mm-rst' into docs-next
Mike Rapoport says: These patches convert files in Documentation/vm to ReST format, add an initial index and link it to the top level documentation. There are no contents changes in the documentation, except few spelling fixes. The relatively large diffstat stems from the indentation and paragraph wrapping changes. I've tried to keep the formatting as consistent as possible, but I could miss some places that needed markup and add some markup where it was not necessary. [jc: significant conflicts in vm/hmm.rst] |
||
Mike Rapoport
|
ad56b738c5 |
docs/vm: rename documentation files to .rst
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
||
Tetsuo Handa
|
8e04944f0e |
mm,vmscan: Allow preallocating memory for register_shrinker().
syzbot is catching so many bugs triggered by commit
|
||
Vlastimil Babka
|
a9f2a846f0 |
mm, slab: reschedule cache_reap() on the same CPU
cache_reap() is initially scheduled in start_cpu_timer() via schedule_delayed_work_on(). But then the next iterations are scheduled via schedule_delayed_work(), i.e. using WORK_CPU_UNBOUND. Thus since commit |
||
Arnd Bergmann
|
453972283d |
mm/filemap.c: provide dummy filemap_page_mkwrite() for NOMMU
Building orangefs on MMU-less machines now results in a link error
because of the newly introduced use of the filemap_page_mkwrite()
function:
ERROR: "filemap_page_mkwrite" [fs/orangefs/orangefs.ko] undefined!
This adds a dummy version for it, similar to the existing
generic_file_mmap and generic_file_readonly_mmap stubs in the same file,
to avoid the link error without adding #ifdefs in each file system that
uses these.
Link: http://lkml.kernel.org/r/20180409105555.2439976-1-arnd@arndb.de
Fixes:
|
||
Michael S. Tsirkin
|
d081107867 |
mm/gup.c: document return value
__get_user_pages_fast handles errors differently from get_user_pages_fast: the former always returns the number of pages pinned, the later might return a negative error code. Link: http://lkml.kernel.org/r/1522962072-182137-6-git-send-email-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Michael S. Tsirkin
|
c61611f709 |
get_user_pages_fast(): return -EFAULT on access_ok failure
get_user_pages_fast is supposed to be a faster drop-in equivalent of
get_user_pages. As such, callers expect it to return a negative return
code when passed an invalid address, and never expect it to return 0
when passed a positive number of pages, since its documentation says:
* Returns number of pages pinned. This may be fewer than the number
* requested. If nr_pages is 0 or negative, returns 0. If no pages
* were pinned, returns -errno.
When get_user_pages_fast fall back on get_user_pages this is exactly
what happens. Unfortunately the implementation is inconsistent: it
returns 0 if passed a kernel address, confusing callers: for example,
the following is pretty common but does not appear to do the right thing
with a kernel address:
ret = get_user_pages_fast(addr, 1, writeable, &page);
if (ret < 0)
return ret;
Change get_user_pages_fast to return -EFAULT when supplied a kernel
address to make it match expectations.
All callers have been audited for consistency with the documented
semantics.
Link: http://lkml.kernel.org/r/1522962072-182137-4-git-send-email-mst@redhat.com
Fixes:
|
||
Michael S. Tsirkin
|
09e35a4a1c |
mm/gup_benchmark: handle gup failures
Patch series "mm/get_user_pages_fast fixes, cleanups", v2. Turns out get_user_pages_fast and __get_user_pages_fast return different values on error when given a single page: __get_user_pages_fast returns 0. get_user_pages_fast returns either 0 or an error. Callers of get_user_pages_fast expect an error so fix it up to return an error consistently. Stress the difference between get_user_pages_fast and __get_user_pages_fast to make sure callers aren't confused. This patch (of 3): __gup_benchmark_ioctl does not handle the case where get_user_pages_fast fails: - a negative return code will cause a buffer overrun - returning with partial success will cause use of uninitialized memory. [akpm@linux-foundation.org: simplification] Link: http://lkml.kernel.org/r/1522962072-182137-3-git-send-email-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Matthew Wilcox
|
b93b016313 |
page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to the radix_tree_root. Rename the address_space ->page_tree to ->i_pages, since we don't really care that it's a tree. [willy@infradead.org: fix nds32, fs/dax.c] Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Jeff Layton <jlayton@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Pavel Tatashin
|
6f84f8d158 |
xen, mm: allow deferred page initialization for xen pv domains
Juergen Gross noticed that commit
|
||
Michal Hocko
|
a4ff8e8620 |
mm: introduce MAP_FIXED_NOREPLACE
Patch series "mm: introduce MAP_FIXED_NOREPLACE", v2. This has started as a follow up discussion [3][4] resulting in the runtime failure caused by hardening patch [5] which removes MAP_FIXED from the elf loader because MAP_FIXED is inherently dangerous as it might silently clobber an existing underlying mapping (e.g. stack). The reason for the failure is that some architectures enforce an alignment for the given address hint without MAP_FIXED used (e.g. for shared or file backed mappings). One way around this would be excluding those archs which do alignment tricks from the hardening [6]. The patch is really trivial but it has been objected, rightfully so, that this screams for a more generic solution. We basically want a non-destructive MAP_FIXED. The first patch introduced MAP_FIXED_NOREPLACE which enforces the given address but unlike MAP_FIXED it fails with EEXIST if the given range conflicts with an existing one. The flag is introduced as a completely new one rather than a MAP_FIXED extension because of the backward compatibility. We really want a never-clobber semantic even on older kernels which do not recognize the flag. Unfortunately mmap sucks wrt flags evaluation because we do not EINVAL on unknown flags. On those kernels we would simply use the traditional hint based semantic so the caller can still get a different address (which sucks) but at least not silently corrupt an existing mapping. I do not see a good way around that. Except we won't export expose the new semantic to the userspace at all. It seems there are users who would like to have something like that. Jemalloc has been mentioned by Michael Ellerman [7] Florian Weimer has mentioned the following: : glibc ld.so currently maps DSOs without hints. This means that the kernel : will map right next to each other, and the offsets between them a completely : predictable. We would like to change that and supply a random address in a : window of the address space. If there is a conflict, we do not want the : kernel to pick a non-random address. Instead, we would try again with a : random address. John Hubbard has mentioned CUDA example : a) Searches /proc/<pid>/maps for a "suitable" region of available : VA space. "Suitable" generally means it has to have a base address : within a certain limited range (a particular device model might : have odd limitations, for example), it has to be large enough, and : alignment has to be large enough (again, various devices may have : constraints that lead us to do this). : : This is of course subject to races with other threads in the process. : : Let's say it finds a region starting at va. : : b) Next it does: : p = mmap(va, ...) : : *without* setting MAP_FIXED, of course (so va is just a hint), to : attempt to safely reserve that region. If p != va, then in most cases, : this is a failure (almost certainly due to another thread getting a : mapping from that region before we did), and so this layer now has to : call munmap(), before returning a "failure: retry" to upper layers. : : IMPROVEMENT: --> if instead, we could call this: : : p = mmap(va, ... MAP_FIXED_NOREPLACE ...) : : , then we could skip the munmap() call upon failure. This : is a small thing, but it is useful here. (Thanks to Piotr : Jaroszynski and Mark Hairgrove for helping me get that detail : exactly right, btw.) : : c) After that, CUDA suballocates from p, via: : : q = mmap(sub_region_start, ... MAP_FIXED ...) : : Interestingly enough, "freeing" is also done via MAP_FIXED, and : setting PROT_NONE to the subregion. Anyway, I just included (c) for : general interest. Atomic address range probing in the multithreaded programs in general sounds like an interesting thing to me. The second patch simply replaces MAP_FIXED use in elf loader by MAP_FIXED_NOREPLACE. I believe other places which rely on MAP_FIXED should follow. Actually real MAP_FIXED usages should be docummented properly and they should be more of an exception. [1] http://lkml.kernel.org/r/20171116101900.13621-1-mhocko@kernel.org [2] http://lkml.kernel.org/r/20171129144219.22867-1-mhocko@kernel.org [3] http://lkml.kernel.org/r/20171107162217.382cd754@canb.auug.org.au [4] http://lkml.kernel.org/r/1510048229.12079.7.camel@abdul.in.ibm.com [5] http://lkml.kernel.org/r/20171023082608.6167-1-mhocko@kernel.org [6] http://lkml.kernel.org/r/20171113094203.aofz2e7kueitk55y@dhcp22.suse.cz [7] http://lkml.kernel.org/r/87efp1w7vy.fsf@concordia.ellerman.id.au This patch (of 2): MAP_FIXED is used quite often to enforce mapping at the particular range. The main problem of this flag is, however, that it is inherently dangerous because it unmaps existing mappings covered by the requested range. This can cause silent memory corruptions. Some of them even with serious security implications. While the current semantic might be really desiderable in many cases there are others which would want to enforce the given range but rather see a failure than a silent memory corruption on a clashing range. Please note that there is no guarantee that a given range is obeyed by the mmap even when it is free - e.g. arch specific code is allowed to apply an alignment. Introduce a new MAP_FIXED_NOREPLACE flag for mmap to achieve this behavior. It has the same semantic as MAP_FIXED wrt. the given address request with a single exception that it fails with EEXIST if the requested address is already covered by an existing mapping. We still do rely on get_unmaped_area to handle all the arch specific MAP_FIXED treatment and check for a conflicting vma after it returns. The flag is introduced as a completely new one rather than a MAP_FIXED extension because of the backward compatibility. We really want a never-clobber semantic even on older kernels which do not recognize the flag. Unfortunately mmap sucks wrt. flags evaluation because we do not EINVAL on unknown flags. On those kernels we would simply use the traditional hint based semantic so the caller can still get a different address (which sucks) but at least not silently corrupt an existing mapping. I do not see a good way around that. [mpe@ellerman.id.au: fix whitespace] [fail on clashing range with EEXIST as per Florian Weimer] [set MAP_FIXED before round_hint_to_min as per Khalid Aziz] Link: http://lkml.kernel.org/r/20171213092550.2774-2-mhocko@kernel.org Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: Russell King - ARM Linux <linux@armlinux.org.uk> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Joel Stanley <joel@jms.id.au> Cc: Kees Cook <keescook@chromium.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Jason Evans <jasone@google.com> Cc: David Goldblatt <davidtgoldblatt@gmail.com> Cc: Edward Tomasz Napierała <trasz@FreeBSD.org> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Kees Cook
|
8f2af155b5 |
exec: pass stack rlimit into mm layout functions
Patch series "exec: Pin stack limit during exec". Attempts to solve problems with the stack limit changing during exec continue to be frustrated[1][2]. In addition to the specific issues around the Stack Clash family of flaws, Andy Lutomirski pointed out[3] other places during exec where the stack limit is used and is assumed to be unchanging. Given the many places it gets used and the fact that it can be manipulated/raced via setrlimit() and prlimit(), I think the only way to handle this is to move away from the "current" view of the stack limit and instead attach it to the bprm, and plumb this down into the functions that need to know the stack limits. This series implements the approach. [1] |
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Andrey Konovalov
|
c3895391df |
kasan, slub: fix handling of kasan_slab_free hook
The kasan_slab_free hook's return value denotes whether the reuse of a slab object must be delayed (e.g. when the object is put into memory qurantine). The current way SLUB handles this hook is by ignoring its return value and hardcoding checks similar (but not exactly the same) to the ones performed in kasan_slab_free, which is prone to making mistakes. The main difference between the hardcoded checks and the ones in kasan_slab_free is whether we want to perform a free in case when an invalid-free or a double-free was detected (we don't). This patch changes the way SLUB handles this by: 1. taking into account the return value of kasan_slab_free for each of the objects, that are being freed; 2. reconstructing the freelist of objects to exclude the ones, whose reuse must be delayed. [andreyknvl@google.com: eliminate unnecessary branch in slab_free] Link: http://lkml.kernel.org/r/a62759a2545fddf69b0c034547212ca1eb1b3ce2.1520359686.git.andreyknvl@google.com Link: http://lkml.kernel.org/r/083f58501e54731203801d899632d76175868e97.1519400992.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Kostya Serebryany <kcc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Joonsoo Kim
|
b7d349c741 |
mm/thp: don't count ZONE_MOVABLE as the target for freepage reserving
There was a regression report for "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE" [1] and I think that it is related to this problem. CMA patchset makes the system use one more zone (ZONE_MOVABLE) and then increases min_free_kbytes. It reduces usable memory and it could cause regression. ZONE_MOVABLE only has movable pages so we don't need to keep enough freepages to avoid or deal with fragmentation. So, don't count it. This changes min_free_kbytes and thus min_watermark greatly if ZONE_MOVABLE is used. It will make the user uses more memory. System: 22GB ram, fakenuma, 2 nodes. 5 zones are used. Before: min_free_kbytes: 112640 zone_info (min_watermark): Node 0, zone DMA min 19 Node 0, zone DMA32 min 3778 Node 0, zone Normal min 10191 Node 0, zone Movable min 0 Node 0, zone Device min 0 Node 1, zone DMA min 0 Node 1, zone DMA32 min 0 Node 1, zone Normal min 14043 Node 1, zone Movable min 127 Node 1, zone Device min 0 After: min_free_kbytes: 90112 zone_info (min_watermark): Node 0, zone DMA min 15 Node 0, zone DMA32 min 3022 Node 0, zone Normal min 8152 Node 0, zone Movable min 0 Node 0, zone Device min 0 Node 1, zone DMA min 0 Node 1, zone DMA32 min 0 Node 1, zone Normal min 11234 Node 1, zone Movable min 102 Node 1, zone Device min 0 [1] (lkml.kernel.org/r/20180102063528.GG30397%20()%20yexl-desktop) Link: http://lkml.kernel.org/r/1522913236-15776-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Joonsoo Kim
|
1d47a3ec09 |
mm/cma: remove ALLOC_CMA
Now, all reserved pages for CMA region are belong to the ZONE_MOVABLE and it only serves for a request with GFP_HIGHMEM && GFP_MOVABLE. Therefore, we don't need to maintain ALLOC_CMA at all. Link: http://lkml.kernel.org/r/1512114786-5085-3-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Joonsoo Kim
|
bad8c6c0b1 |
mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE
Patch series "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE", v2. 0. History This patchset is the follow-up of the discussion about the "Introduce ZONE_CMA (v7)" [1]. Please reference it if more information is needed. 1. What does this patch do? This patch changes the management way for the memory of the CMA area in the MM subsystem. Currently the memory of the CMA area is managed by the zone where their pfn is belong to. However, this approach has some problems since MM subsystem doesn't have enough logic to handle the situation that different characteristic memories are in a single zone. To solve this issue, this patch try to manage all the memory of the CMA area by using the MOVABLE zone. In MM subsystem's point of view, characteristic of the memory on the MOVABLE zone and the memory of the CMA area are the same. So, managing the memory of the CMA area by using the MOVABLE zone will not have any problem. 2. Motivation There are some problems with current approach. See following. Although these problem would not be inherent and it could be fixed without this conception change, it requires many hooks addition in various code path and it would be intrusive to core MM and would be really error-prone. Therefore, I try to solve them with this new approach. Anyway, following is the problems of the current implementation. o CMA memory utilization First, following is the freepage calculation logic in MM. - For movable allocation: freepage = total freepage - For unmovable allocation: freepage = total freepage - CMA freepage Freepages on the CMA area is used after the normal freepages in the zone where the memory of the CMA area is belong to are exhausted. At that moment that the number of the normal freepages is zero, so - For movable allocation: freepage = total freepage = CMA freepage - For unmovable allocation: freepage = 0 If unmovable allocation comes at this moment, allocation request would fail to pass the watermark check and reclaim is started. After reclaim, there would exist the normal freepages so freepages on the CMA areas would not be used. FYI, there is another attempt [2] trying to solve this problem in lkml. And, as far as I know, Qualcomm also has out-of-tree solution for this problem. Useless reclaim: There is no logic to distinguish CMA pages in the reclaim path. Hence, CMA page is reclaimed even if the system just needs the page that can be usable for the kernel allocation. Atomic allocation failure: This is also related to the fallback allocation policy for the memory of the CMA area. Consider the situation that the number of the normal freepages is *zero* since the bunch of the movable allocation requests come. Kswapd would not be woken up due to following freepage calculation logic. - For movable allocation: freepage = total freepage = CMA freepage If atomic unmovable allocation request comes at this moment, it would fails due to following logic. - For unmovable allocation: freepage = total freepage - CMA freepage = 0 It was reported by Aneesh [3]. Useless compaction: Usual high-order allocation request is unmovable allocation request and it cannot be served from the memory of the CMA area. In compaction, migration scanner try to migrate the page in the CMA area and make high-order page there. As mentioned above, it cannot be usable for the unmovable allocation request so it's just waste. 3. Current approach and new approach Current approach is that the memory of the CMA area is managed by the zone where their pfn is belong to. However, these memory should be distinguishable since they have a strong limitation. So, they are marked as MIGRATE_CMA in pageblock flag and handled specially. However, as mentioned in section 2, the MM subsystem doesn't have enough logic to deal with this special pageblock so many problems raised. New approach is that the memory of the CMA area is managed by the MOVABLE zone. MM already have enough logic to deal with special zone like as HIGHMEM and MOVABLE zone. So, managing the memory of the CMA area by the MOVABLE zone just naturally work well because constraints for the memory of the CMA area that the memory should always be migratable is the same with the constraint for the MOVABLE zone. There is one side-effect for the usability of the memory of the CMA area. The use of MOVABLE zone is only allowed for a request with GFP_HIGHMEM && GFP_MOVABLE so now the memory of the CMA area is also only allowed for this gfp flag. Before this patchset, a request with GFP_MOVABLE can use them. IMO, It would not be a big issue since most of GFP_MOVABLE request also has GFP_HIGHMEM flag. For example, file cache page and anonymous page. However, file cache page for blockdev file is an exception. Request for it has no GFP_HIGHMEM flag. There is pros and cons on this exception. In my experience, blockdev file cache pages are one of the top reason that causes cma_alloc() to fail temporarily. So, we can get more guarantee of cma_alloc() success by discarding this case. Note that there is no change in admin POV since this patchset is just for internal implementation change in MM subsystem. Just one minor difference for admin is that the memory stat for CMA area will be printed in the MOVABLE zone. That's all. 4. Result Following is the experimental result related to utilization problem. 8 CPUs, 1024 MB, VIRTUAL MACHINE make -j16 <Before> CMA area: 0 MB 512 MB Elapsed-time: 92.4 186.5 pswpin: 82 18647 pswpout: 160 69839 <After> CMA : 0 MB 512 MB Elapsed-time: 93.1 93.4 pswpin: 84 46 pswpout: 183 92 akpm: "kernel test robot" reported a 26% improvement in vm-scalability.throughput: http://lkml.kernel.org/r/20180330012721.GA3845@yexl-desktop [1]: lkml.kernel.org/r/1491880640-9944-1-git-send-email-iamjoonsoo.kim@lge.com [2]: https://lkml.org/lkml/2014/10/15/623 [3]: http://www.spinics.net/lists/linux-mm/msg100562.html Link: http://lkml.kernel.org/r/1512114786-5085-2-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Joonsoo Kim
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d3cda2337b |
mm/page_alloc: don't reserve ZONE_HIGHMEM for ZONE_MOVABLE request
Freepage on ZONE_HIGHMEM doesn't work for kernel memory so it's not that important to reserve. When ZONE_MOVABLE is used, this problem would theorectically cause to decrease usable memory for GFP_HIGHUSER_MOVABLE allocation request which is mainly used for page cache and anon page allocation. So, fix it by setting 0 to sysctl_lowmem_reserve_ratio[ZONE_HIGHMEM]. And, defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES - 1 size makes code complex. For example, if there is highmem system, following reserve ratio is activated for *NORMAL ZONE* which would be easyily misleading people. #ifdef CONFIG_HIGHMEM 32 #endif This patch also fixes this situation by defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES and place "#ifdef" to right place. Link: http://lkml.kernel.org/r/1504672525-17915-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Tony Lindgren <tony@atomide.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Michal Hocko
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94723aafb9 |
mm: unclutter THP migration
THP migration is hacked into the generic migration with rather surprising semantic. The migration allocation callback is supposed to check whether the THP can be migrated at once and if that is not the case then it allocates a simple page to migrate. unmap_and_move then fixes that up by spliting the THP into small pages while moving the head page to the newly allocated order-0 page. Remaning pages are moved to the LRU list by split_huge_page. The same happens if the THP allocation fails. This is really ugly and error prone [1]. I also believe that split_huge_page to the LRU lists is inherently wrong because all tail pages are not migrated. Some callers will just work around that by retrying (e.g. memory hotplug). There are other pfn walkers which are simply broken though. e.g. madvise_inject_error will migrate head and then advances next pfn by the huge page size. do_move_page_to_node_array, queue_pages_range (migrate_pages, mbind), will simply split the THP before migration if the THP migration is not supported then falls back to single page migration but it doesn't handle tail pages if the THP migration path is not able to allocate a fresh THP so we end up with ENOMEM and fail the whole migration which is a questionable behavior. Page compaction doesn't try to migrate large pages so it should be immune. This patch tries to unclutter the situation by moving the special THP handling up to the migrate_pages layer where it actually belongs. We simply split the THP page into the existing list if unmap_and_move fails with ENOMEM and retry. So we will _always_ migrate all THP subpages and specific migrate_pages users do not have to deal with this case in a special way. [1] http://lkml.kernel.org/r/20171121021855.50525-1-zi.yan@sent.com Link: http://lkml.kernel.org/r/20180103082555.14592-4-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Michal Hocko
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666feb21a0 |
mm, migrate: remove reason argument from new_page_t
No allocation callback is using this argument anymore. new_page_node used to use this parameter to convey node_id resp. migration error up to move_pages code (do_move_page_to_node_array). The error status never made it into the final status field and we have a better way to communicate node id to the status field now. All other allocation callbacks simply ignored the argument so we can drop it finally. [mhocko@suse.com: fix migration callback] Link: http://lkml.kernel.org/r/20180105085259.GH2801@dhcp22.suse.cz [akpm@linux-foundation.org: fix alloc_misplaced_dst_page()] [mhocko@kernel.org: fix build] Link: http://lkml.kernel.org/r/20180103091134.GB11319@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20180103082555.14592-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Michal Hocko
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a49bd4d716 |
mm, numa: rework do_pages_move
Patch series "unclutter thp migration" Motivation: THP migration is hacked into the generic migration with rather surprising semantic. The migration allocation callback is supposed to check whether the THP can be migrated at once and if that is not the case then it allocates a simple page to migrate. unmap_and_move then fixes that up by splitting the THP into small pages while moving the head page to the newly allocated order-0 page. Remaining pages are moved to the LRU list by split_huge_page. The same happens if the THP allocation fails. This is really ugly and error prone [2]. I also believe that split_huge_page to the LRU lists is inherently wrong because all tail pages are not migrated. Some callers will just work around that by retrying (e.g. memory hotplug). There are other pfn walkers which are simply broken though. e.g. madvise_inject_error will migrate head and then advances next pfn by the huge page size. do_move_page_to_node_array, queue_pages_range (migrate_pages, mbind), will simply split the THP before migration if the THP migration is not supported then falls back to single page migration but it doesn't handle tail pages if the THP migration path is not able to allocate a fresh THP so we end up with ENOMEM and fail the whole migration which is a questionable behavior. Page compaction doesn't try to migrate large pages so it should be immune. The first patch reworks do_pages_move which relies on a very ugly calling semantic when the return status is pushed to the migration path via private pointer. It uses pre allocated fixed size batching to achieve that. We simply cannot do the same if a THP is to be split during the migration path which is done in the patch 3. Patch 2 is follow up cleanup which removes the mentioned return status calling convention ugliness. On a side note: There are some semantic issues I have encountered on the way when working on patch 1 but I am not addressing them here. E.g. trying to move THP tail pages will result in either success or EBUSY (the later one more likely once we isolate head from the LRU list). Hugetlb reports EACCESS on tail pages. Some errors are reported via status parameter but migration failures are not even though the original `reason' argument suggests there was an intention to do so. From a quick look into git history this never worked. I have tried to keep the semantic unchanged. Then there is a relatively minor thing that the page isolation might fail because of pages not being on the LRU - e.g. because they are sitting on the per-cpu LRU caches. Easily fixable. This patch (of 3): do_pages_move is supposed to move user defined memory (an array of addresses) to the user defined numa nodes (an array of nodes one for each address). The user provided status array then contains resulting numa node for each address or an error. The semantic of this function is little bit confusing because only some errors are reported back. Notably migrate_pages error is only reported via the return value. This patch doesn't try to address these semantic nuances but rather change the underlying implementation. Currently we are processing user input (which can be really large) in batches which are stored to a temporarily allocated page. Each address is resolved to its struct page and stored to page_to_node structure along with the requested target numa node. The array of these structures is then conveyed down the page migration path via private argument. new_page_node then finds the corresponding structure and allocates the proper target page. What is the problem with the current implementation and why to change it? Apart from being quite ugly it also doesn't cope with unexpected pages showing up on the migration list inside migrate_pages path. That doesn't happen currently but the follow up patch would like to make the thp migration code more clear and that would need to split a THP into the list for some cases. How does the new implementation work? Well, instead of batching into a fixed size array we simply batch all pages that should be migrated to the same node and isolate all of them into a linked list which doesn't require any additional storage. This should work reasonably well because page migration usually migrates larger ranges of memory to a specific node. So the common case should work equally well as the current implementation. Even if somebody constructs an input where the target numa nodes would be interleaved we shouldn't see a large performance impact because page migration alone doesn't really benefit from batching. mmap_sem batching for the lookup is quite questionable and isolate_lru_page which would benefit from batching is not using it even in the current implementation. Link: http://lkml.kernel.org/r/20180103082555.14592-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Colin Ian King
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bfc6b1cabc |
mm/swapfile.c: make pointer swap_avail_heads static
The pointer swap_avail_heads is local to the source and does not need to be in global scope, so make it static. Cleans up sparse warning: mm/swapfile.c:88:19: warning: symbol 'swap_avail_heads' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20180206215836.12366-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Michal Hocko
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4eaf431f6f |
memcg: fix per_node_info cleanup
syzbot has triggered a NULL ptr dereference when allocation fault
injection enforces a failure and alloc_mem_cgroup_per_node_info
initializes memcg->nodeinfo only half way through.
But __mem_cgroup_free still tries to free all per-node data and
dereferences pn->lruvec_stat_cpu unconditioanlly even if the specific
per-node data hasn't been initialized.
The bug is quite unlikely to hit because small allocations do not fail
and we would need quite some numa nodes to make struct
mem_cgroup_per_node large enough to cross the costly order.
Link: http://lkml.kernel.org/r/20180406100906.17790-1-mhocko@kernel.org
Reported-by: syzbot+8a5de3cce7cdc70e9ebe@syzkaller.appspotmail.com
Fixes:
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Tom Abraham
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a06ad633a3 |
swap: divide-by-zero when zero length swap file on ssd
Calling swapon() on a zero length swap file on SSD can lead to a divide-by-zero. Although creating such files isn't possible with mkswap and they woud be considered invalid, it would be better for the swapon code to be more robust and handle this condition gracefully (return -EINVAL). Especially since the fix is small and straightforward. To help with wear leveling on SSD, the swapon syscall calculates a random position in the swap file using modulo p->highest_bit, which is set to maxpages - 1 in read_swap_header. If the swap file is zero length, read_swap_header sets maxpages=1 and last_page=0, resulting in p->highest_bit=0 and we divide-by-zero when we modulo p->highest_bit in swapon syscall. This can be prevented by having read_swap_header return zero if last_page is zero. Link: http://lkml.kernel.org/r/5AC747C1020000A7001FA82C@prv-mh.provo.novell.com Signed-off-by: Thomas Abraham <tabraham@suse.com> Reported-by: <Mark.Landis@Teradata.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
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e27be240df |
mm: memcg: make sure memory.events is uptodate when waking pollers
Commit |
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Claudio Imbrenda
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a38c015f31 |
mm/ksm.c: fix inconsistent accounting of zero pages
When using KSM with use_zero_pages, we replace anonymous pages
containing only zeroes with actual zero pages, which are not anonymous.
We need to do proper accounting of the mm counters, otherwise we will
get wrong values in /proc and a BUG message in dmesg when tearing down
the mm.
Link: http://lkml.kernel.org/r/1522931274-15552-1-git-send-email-imbrenda@linux.vnet.ibm.com
Fixes:
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