When I removed the per-zone bitlock hashed waitqueues in commit
9dcb8b685f ("mm: remove per-zone hashtable of bitlock waitqueues"), I
removed all the magic hotplug memory initialization of said waitqueues
too.
But when I actually _tested_ the resulting build, I stupidly assumed
that "allmodconfig" would enable memory hotplug. And it doesn't,
because it enables KASAN instead, which then disables hotplug memory
support.
As a result, my build test of the per-zone waitqueues was totally
broken, and I didn't notice that the compiler warns about the now unused
iterator variable 'i'.
I guess I should be happy that that seems to be the worst breakage from
my clearly horribly failed test coverage.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull i2c fixes from Wolfram Sang:
"I2C has some driver bugfixes, module autoload fixes, and driver
enablement on some architectures"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: imx: defer probe if bus recovery GPIOs are not ready
i2c: designware: Avoid aborted transfers with fast reacting I2C slaves
i2c: i801: Fix I2C Block Read on 8-Series/C220 and later
i2c: xgene: Avoid dma_buffer overrun
i2c: digicolor: Fix module autoload
i2c: xlr: Fix module autoload for OF registration
i2c: xlp9xx: Fix module autoload
i2c: jz4780: Fix module autoload
i2c: allow configuration of imx driver for ColdFire architecture
i2c: mark device nodes only in case of successful instantiation
i2c: rk3x: Give the tuning value 0 during rk3x_i2c_v0_calc_timings
i2c: hix5hd2: allow build with ARCH_HISI
Pull thermal updates from Zhang Rui:
"The latest Thermal Management updates for v4.9-rc3:
- Fix a regression introduced by commit
b721ca0d19(thermal/powerclamp: remove cpu whitelist), that
powerclamp driver checks cpu support in a wrong way. From: Eric
Ernst.
- Fix a problem that intel_pch_thermal driver misses passive trip
point when the PCH thermal device has an ACPI companion device
associated. From: Srinivas Pandruvada.
- Add missing support for Haswell PCH thermal sensor. From: Srinivas
Pandruvada"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal/powerclamp: correct cpu support check
thermal: intel_pch_thermal: Enable Haswell PCH
thermal: intel_pch_thermal: Add an ACPI passive trip
Pull s390 fixes from Martin Schwidefsky:
"A few more s390 patches for 4.9:
- a fix for an overflow in the dasd driver reported by UBSAN
- fix a regression and add hotplug memory to the zone movable again
- add ignore defines for the pkey system calls
- fix the ouput of the merged stack tracer
- replace printk with pr_cont in arch/s390 where appropriate
- remove the arch specific return_address function again
- ignore reserved channel paths at boot time
- add a missing hugetlb_bad_size call to the arch backend"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: fix zone calculation in arch_add_memory()
s390/dumpstack: use pr_cont within show_stack and die
s390/dumpstack: get rid of return_address again
s390/disassambler: use pr_cont where appropriate
s390/dumpstack: use pr_cont where appropriate
s390/dumpstack: restore reliable indicator for call traces
s390/mm: use hugetlb_bad_size()
s390/cio: don't register chpids in reserved state
s390: ignore pkey system calls
s390/dasd: avoid undefined behaviour
Being a Linux kernel maintainer has been my proudest professional
accomplishment, spanning the last 19 years. But now we have a surfeit
of excellent hackers, and I can hand this over without regret.
I'll still be around as co-maintainer for another cycle, but Jessica
is now the one to convince if you want your patches applied. She
rocks, and is far more timely than me too!
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module maintainership updates from Rusty Russell:
"(Quoting from the MAINTAINERS commit:)
Being a Linux kernel maintainer has been my proudest professional
accomplishment, spanning the last 19 years. But now we have a surfeit
of excellent hackers, and I can hand this over without regret.
I'll still be around as co-maintainer for another cycle, but Jessica
is now the one to convince if you want your patches applied. She
rocks, and is far more timely than me too!"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
MAINTAINERS: Begin module maintainer transition
use d_fsdata instead of d_time
Miklos Szeredi <mszeredi@redhat.com>
use file_inode(file) instead of file->f_path.dentry->d_inode
Amir Goldstein <amir73il@gmail.com>
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Merge tag 'for-linus-4.9-rc2-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull oreangefs updates from Mike Marshall:
"A couple of orangefs cleanups sent in by other developers:
- use d_fsdata instead of d_time (Miklos Szeredi)
- use file_inode(file) instead of file->f_path.dentry->d_inode (Amir
Goldstein)"
* tag 'for-linus-4.9-rc2-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: don't use d_time
orangefs: user file_inode() where it is due
Changes in this update:
o iomap page offset masking fix for page faults
o add IOMAP_REPORT to distinguish between read and fiemap map requests
o cleanups to new shared data extent code
o fix mount active status on failed log recovery
o fix broken dquots in a buffer calculation
o fix locking order issues and merge xfs_reflink_remap_range and
xfs_file_share_range
o rework unmapping of CoW extents and remove now unused functions
o clean state when CoW is done.
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Merge tag 'xfs-fixes-for-linus-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs fixes from Dave Chinner:
"This update contains fixes for most of the outstanding regressions
introduced with the 4.9-rc1 XFS merge. There is also a fix for an
iomap bug, too.
This is a quite a bit larger than I'd prefer for a -rc3, but most of
the change comes from cleaning up the new reflink copy on write code;
it's much simpler and easier to understand now. These changes fixed
several bugs in the new code, and it wasn't clear that there was an
easier/simpler way to fix them. The rest of the fixes are the usual
size you'd expect at this stage.
I've left the commits to soak in linux-next for a some extra time
because of the size before asking you to pull, no new problems with
them have been reported so I think it's all OK.
Summary:
- iomap page offset masking fix for page faults
- add IOMAP_REPORT to distinguish between read and fiemap map
requests
- cleanups to new shared data extent code
- fix mount active status on failed log recovery
- fix broken dquots in a buffer calculation
- fix locking order issues and merge xfs_reflink_remap_range and
xfs_file_share_range
- rework unmapping of CoW extents and remove now unused functions
- clean state when CoW is done"
* tag 'xfs-fixes-for-linus-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (25 commits)
xfs: clear cowblocks tag when cow fork is emptied
xfs: fix up inode cowblocks tracking tracepoints
fs: Do to trim high file position bits in iomap_page_mkwrite_actor
xfs: remove xfs_bunmapi_cow
xfs: optimize xfs_reflink_end_cow
xfs: optimize xfs_reflink_cancel_cow_blocks
xfs: refactor xfs_bunmapi_cow
xfs: optimize writes to reflink files
xfs: don't bother looking at the refcount tree for reads
xfs: handle "raw" delayed extents xfs_reflink_trim_around_shared
xfs: add xfs_trim_extent
iomap: add IOMAP_REPORT
xfs: merge xfs_reflink_remap_range and xfs_file_share_range
xfs: remove xfs_file_wait_for_io
xfs: move inode locking from xfs_reflink_remap_range to xfs_file_share_range
xfs: fix the same_inode check in xfs_file_share_range
xfs: remove the same fs check from xfs_file_share_range
libxfs: v3 inodes are only valid on crc-enabled filesystems
libxfs: clean up _calc_dquots_per_chunk
xfs: unset MS_ACTIVE if mount fails
...
btrfs_remove_all_log_ctxs takes a shortcut where it avoids walking the
list because it knows all of the waiters are patiently waiting for the
commit to finish.
But, there's a small race where btrfs_sync_log can remove itself from
the list if it finds a log commit is already done. Also, it uses
list_del_init() to remove itself from the list, but there's no way to
know if btrfs_remove_all_log_ctxs has already run, so we don't know for
sure if it is safe to call list_del_init().
This gets rid of all the shortcuts for btrfs_remove_all_log_ctxs(), and
just calls it with the proper locking.
This is part two of the corruption fixed by cbd60aa7cd. I should have
done this in the first place, but convinced myself the optimizations were
safe. A 12 hour run of dbench 2048 will eventually trigger a list debug
WARN_ON for the list_del_init() in btrfs_sync_log().
Fixes: d1433debe7
Reported-by: Dave Jones <davej@codemonkey.org.uk>
cc: stable@vger.kernel.org # 3.15+
Signed-off-by: Chris Mason <clm@fb.com>
Two small fixes: one is a fatal section mismatch (reference to init after it's
discarded) and the other two are iscsi locking fixes.
Signed-off-by: James E. J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Two small fixes: one is a fatal section mismatch (reference to init
after it's discarded) and the other two are iscsi locking fixes"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: NCR5380: no longer mark irq probing as __init
scsi: be2iscsi: Replace _bh with _irqsave/irqrestore
scsi: libiscsi: Fix locking in __iscsi_conn_send_pdu
Pull libata fixes from Tejun Heo:
"The AHCI MSI handling change in rc1 was a bit broken and caused disk
probing failures on some machines. These three patches should fix the
issues"
David Howells comments:
"My test machine fell foul of this using a PCIe M.2-attached SSD card.
The patches fix it for me"
* 'for-4.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
ahci: fix the single MSI-X case in ahci_init_one
ahci: fix nvec check
ahci: only try to use multi-MSI mode if there is more than 1 port
Pull block fixes from Jens Axboe:
"A set of fixes for this series, most notably the fix for the blk-mq
software queue regression in from this merge window.
Apart from that, a fix for an unlikely hang if a queue is flooded with
FUA requests from Ming, and a few small fixes for nbd and badblocks.
Lastly, a rename update for the proc softirq output, since the block
polling code was made generic"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq: update hardware and software queues for sleeping alloc
block: flush: fix IO hang in case of flood fua req
nbd: fix incorrect unlock of nbd->sock_lock in sock_shutdown
badblocks: badblocks_set/clear update unacked_exist
softirq: Display IRQ_POLL for irq-poll statistics
The per-zone waitqueues exist because of a scalability issue with the
page waitqueues on some NUMA machines, but it turns out that they hurt
normal loads, and now with the vmalloced stacks they also end up
breaking gfs2 that uses a bit_wait on a stack object:
wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE)
where 'gh' can be a reference to the local variable 'mount_gh' on the
stack of fill_super().
The reason the per-zone hash table breaks for this case is that there is
no "zone" for virtual allocations, and trying to look up the physical
page to get at it will fail (with a BUG_ON()).
It turns out that I actually complained to the mm people about the
per-zone hash table for another reason just a month ago: the zone lookup
also hurts the regular use of "unlock_page()" a lot, because the zone
lookup ends up forcing several unnecessary cache misses and generates
horrible code.
As part of that earlier discussion, we had a much better solution for
the NUMA scalability issue - by just making the page lock have a
separate contention bit, the waitqueue doesn't even have to be looked at
for the normal case.
Peter Zijlstra already has a patch for that, but let's see if anybody
even notices. In the meantime, let's fix the actual gfs2 breakage by
simplifying the bitlock waitqueues and removing the per-zone issue.
Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Tested-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we end up sleeping due to running out of requests, we should
update the hardware and software queues in the map ctx structure.
Otherwise we could end up having rq->mq_ctx point to the pre-sleep
context, and risk corrupting ctx->rq_list since we'll be
grabbing the wrong lock when inserting the request.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Reported-by: Chris Mason <clm@fb.com>
Tested-by: Chris Mason <clm@fb.com>
Fixes: 63581af3f3 ("blk-mq: remove non-blocking pass in blk_mq_map_request")
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch does a couple of things. First of all, powernv immediately
explodes when running a relocated kernel, because the system reset
exception for handling sleeps does not do correct relocated branches.
Secondly, the sleep handling code trashes the condition and cfar
registers, which we would like to preserve for debugging purposes (for
non-sleep case exception).
This patch changes the exception to use the standard format that saves
registers before any tests or branches are made. It adds the test for
idle-wakeup as an "extra" to break out of the normal exception path.
Then it branches to a relocated idle handler that calls the various
idle handling functions.
After this patch, POWER8 CPU simulator now boots powernv kernel that is
running at non-zero.
Fixes: 948cf67c47 ("powerpc: Add NAP mode support on Power7 in HV mode")
Cc: stable@vger.kernel.org # v3.0+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Before this patch, we used tlbiel, if we ever ran only on this core.
That was mostly derived from the nohash usage of the same. But is
incorrect, the ISA 3.0 clarifies tlbiel such that:
"All TLB entries that have all of the following properties are made
invalid on the thread executing the tlbiel instruction"
ie. tlbiel only invalidates TLB entries on the current thread. So if the
mm has been used on any other thread (aka. cpu) then we must broadcast
the invalidate.
This bug could lead to invalid TLB entries if a program runs on multiple
threads of a core.
Hence use tlbiel, if we only ever ran on only the current cpu.
Fixes: 1a472c9dba ("powerpc/mm/radix: Add tlbflush routines")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It should be ALTIVEC, not ALIVEC.
Cyril explains: If a thread performs a transaction with altivec and then
gets preempted for whatever reason, this bug may cause the kernel to not
re-enable altivec when that thread runs again. This will result in an
altivec unavailable fault, when that fault happens inside a user
transaction the kernel has no choice but to enable altivec and doom the
transaction.
The result is that transactions using altivec may get aborted more often
than they should.
The difficulty in catching this with a selftest is my deliberate use of
the word may above. Optimisations to avoid FPU/altivec/VSX faults mean
that the kernel will always leave them on for 255 switches. This code
prevents the kernel turning it off if it got to the 256th switch (and
userspace was transactional).
Fixes: dc16b553c9 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use")
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since commit:
8663e24d56 ("sched/fair: Reorder cgroup creation code")
... the variable 'rq' in alloc_fair_sched_group() is set but no longer used.
Remove it to fix the following GCC warning when building with 'W=1':
kernel/sched/fair.c:8842:13: warning: variable ‘rq’ set but not used [-Wunused-but-set-variable]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161026113704.8981-1-tklauser@distanz.ch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following commit:
3732710ff6 ("objtool: Improve rare switch jump table pattern detection")
... improved objtool's ability to detect GCC switch statement jump
tables for GCC 6. However the check to allow short jumps with the
scanned range of instructions wasn't quite right. The pattern detection
should allow jumps to the indirect jump instruction itself.
This fixes the following warning:
drivers/infiniband/sw/rxe/rxe_comp.o: warning: objtool: rxe_completer()+0x315: sibling call from callable instruction with changed frame pointer
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 3732710ff6 ("objtool: Improve rare switch jump table pattern detection")
Link: http://lkml.kernel.org/r/20161026153408.2rifnw7bvoc5sex7@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since BIG_KEYS can't be compiled as module it requires one of the "stdrng"
providers to be compiled into kernel. Otherwise big_key_crypto_init() fails
on crypto_alloc_rng step and next dereference of big_key_skcipher (e.g. in
big_key_preparse()) results in a NULL pointer dereference.
Fixes: 13100a72f4 ('Security: Keys: Big keys stored encrypted')
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Stephan Mueller <smueller@chronox.de>
cc: Kirill Marinushkin <k.marinushkin@gmail.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
big_key has two separate initialisation functions, one that registers the
key type and one that registers the crypto. If the key type fails to
register, there's no problem if the crypto registers successfully because
there's no way to reach the crypto except through the key type.
However, if the key type registers successfully but the crypto does not,
big_key_rng and big_key_blkcipher may end up set to NULL - but the code
neither checks for this nor unregisters the big key key type.
Furthermore, since the key type is registered before the crypto, it is
theoretically possible for the kernel to try adding a big_key before the
crypto is set up, leading to the same effect.
Fix this by merging big_key_crypto_init() and big_key_init() and calling
the resulting function late. If they're going to be encrypted, we
shouldn't be creating big_keys before we have the facilities to do the
encryption available. The key type registration is also moved after the
crypto initialisation.
The fix also includes message printing on failure.
If the big_key type isn't correctly set up, simply doing:
dd if=/dev/zero bs=4096 count=1 | keyctl padd big_key a @s
ought to cause an oops.
Fixes: 13100a72f4 ('Security: Keys: Big keys stored encrypted')
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Peter Hlavaty <zer0mem@yahoo.com>
cc: Kirill Marinushkin <k.marinushkin@gmail.com>
cc: Artem Savkov <asavkov@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
This fixes CVE-2016-7042.
Fix a short sprintf buffer in proc_keys_show(). If the gcc stack protector
is turned on, this can cause a panic due to stack corruption.
The problem is that xbuf[] is not big enough to hold a 64-bit timeout
rendered as weeks:
(gdb) p 0xffffffffffffffffULL/(60*60*24*7)
$2 = 30500568904943
That's 14 chars plus NUL, not 11 chars plus NUL.
Expand the buffer to 16 chars.
I think the unpatched code apparently works if the stack-protector is not
enabled because on a 32-bit machine the buffer won't be overflowed and on a
64-bit machine there's a 64-bit aligned pointer at one side and an int that
isn't checked again on the other side.
The panic incurred looks something like:
Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81352ebe
CPU: 0 PID: 1692 Comm: reproducer Not tainted 4.7.2-201.fc24.x86_64 #1
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
0000000000000086 00000000fbbd2679 ffff8800a044bc00 ffffffff813d941f
ffffffff81a28d58 ffff8800a044bc98 ffff8800a044bc88 ffffffff811b2cb6
ffff880000000010 ffff8800a044bc98 ffff8800a044bc30 00000000fbbd2679
Call Trace:
[<ffffffff813d941f>] dump_stack+0x63/0x84
[<ffffffff811b2cb6>] panic+0xde/0x22a
[<ffffffff81352ebe>] ? proc_keys_show+0x3ce/0x3d0
[<ffffffff8109f7f9>] __stack_chk_fail+0x19/0x30
[<ffffffff81352ebe>] proc_keys_show+0x3ce/0x3d0
[<ffffffff81350410>] ? key_validate+0x50/0x50
[<ffffffff8134db30>] ? key_default_cmp+0x20/0x20
[<ffffffff8126b31c>] seq_read+0x2cc/0x390
[<ffffffff812b6b12>] proc_reg_read+0x42/0x70
[<ffffffff81244fc7>] __vfs_read+0x37/0x150
[<ffffffff81357020>] ? security_file_permission+0xa0/0xc0
[<ffffffff81246156>] vfs_read+0x96/0x130
[<ffffffff81247635>] SyS_read+0x55/0xc0
[<ffffffff817eb872>] entry_SYSCALL_64_fastpath+0x1a/0xa4
Reported-by: Ondrej Kozina <okozina@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ondrej Kozina <okozina@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
Fix parameter name for __page_to_voff, to match its definition.
At present, we don't see any issue, as page_to_virt's caller
declares 'page'.
Fixes: 9f2875912d ("arm64: mm: restrict virt_to_page() to the linear mapping")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
When booting on NUMA system with memory-less node (no
memory dimm on this memory controller), the print
for setup_node_data() is incorrect:
NUMA: Initmem setup node 2 [mem 0x00000000-0xffffffffffffffff]
It can be fixed by printing [mem 0x00000000-0x00000000] when
end_pfn is 0, but print <memory-less node> will be more useful.
Fixes: 1a2db30034 ("arm64, numa: Add NUMA support for arm64 platforms.")
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch fixes one issue reported by Kent, which can
be triggered in bcachefs over sata disk. Actually it
is a generic issue in block flush vs. blk-tag.
Cc: Christoph Hellwig <hch@infradead.org>
Reported-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit 784d5699ed ("x86: move exports to actual definitions") removed the
EXPORT_SYMBOL(__fentry__) and EXPORT_SYMBOL(mcount) from x8664_ksyms_64.c,
and added EXPORT_SYMBOL(function_hook) in mcount_64.S instead. The problem
is that function_hook isn't a function at all, but a macro that is defined
as either mcount or __fentry__ depending on the support from gcc.
Originally, I thought this was a macro issue, like what __stringify()
is used for. But the problem is a bit deeper. The Makefile.build has
some magic that does post processing of files to create the CRC
bindings. It does some searches for EXPORT_SYMBOL() and because it
finds a macro name and not the actual functions, this causes
function_hook not to be converted into mcount or __fentry__ and they
are missed.
Instead of adding more magic to Makefile.build, just add
EXPORT_SYMBOL() for mcount and __fentry__ where the ifdef is used.
Since this is assembly and not C, it doesn't require being set after
the function is defined.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Borislav Petkov <bp@alien8.de>
Cc: Gabriel C <nix.or.die@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Link: http://lkml.kernel.org/r/20161024150148.4f9d90e4@gandalf.local.home
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
commit 92ca8d20dee2 ("genirq/msi: Switch to new irq spreading")
introduced new parameter to msi_init_setup and but did not update
docbook comments. Fixes 'make htmldocs' warning.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: bhelgaas@google.com
Cc: linux-pci@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This fixes a regression in all these drivers since the cache
mode tracking was fixed for mixed mappings. It uses the new
arch API to add the VRAM range to the PAT mapping tracking
tables.
Fixes: 87744ab383 (mm: fix cache mode tracking in vm_insert_mixed())
Reviewed-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: Dave Airlie <airlied@redhat.com>
A recent change to the mm code in:
87744ab383 mm: fix cache mode tracking in vm_insert_mixed()
started enforcing checking the memory type against the registered list for
amixed pfn insertion mappings. It happens that the drm drivers for a number
of gpus relied on this being broken. Currently the driver only inserted
VRAM mappings into the tracking table when they came from the kernel,
and userspace mappings never landed in the table. This led to a regression
where all the mapping end up as UC instead of WC now.
I've considered a number of solutions but since this needs to be fixed
in fixes and not next, and some of the solutions were going to introduce
overhead that hadn't been there before I didn't consider them viable at
this stage. These mainly concerned hooking into the TTM io reserve APIs,
but these API have a bunch of fast paths I didn't want to unwind to add
this to.
The solution I've decided on is to add a new API like the arch_phys_wc
APIs (these would have worked but wc_del didn't take a range), and
use them from the drivers to add a WC compatible mapping to the table
for all VRAM on those GPUs. This means we can then create userspace
mapping that won't get degraded to UC.
v1.1: use CONFIG_X86_PAT + add some comments in io.h
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: x86@kernel.org
Cc: mcgrof@suse.com
Cc: Dan Williams <dan.j.williams@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Being a Linux kernel maintainer has been my proudest professional
accomplishment, spanning the last 19 years. But now we have a surfeit
of excellent hackers, and I can hand this over without regret.
I'll still be around as co-maintainer for another cycle, but Jessica
is now the one to convince if you want your patches applied. She
rocks, and is far more timely than me too!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Jessica Yu <jeyu@redhat.com>
We need to make sure hpriv->irq is set properly if we don't use per-port
vectors, so switch from blindly assigning pdev->irq to using
pci_irq_vector, which handles all interrupt types correctly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Robert Richter <robert.richter@cavium.com>
Tested-by: Robert Richter <robert.richter@cavium.com>
Tested-by: David Daney <ddaney.cavm@gmail.com>
Fixes: 0b9e2988ab ("ahci: use pci_alloc_irq_vectors")
Signed-off-by: Tejun Heo <tj@kernel.org>
When a timer is enqueued we try to forward the timer base clock. This
mechanism has two issues:
1) Forwarding a remote base unlocked
The forwarding function is called from get_target_base() with the current
timer base lock held. But if the new target base is a different base than
the current base (can happen with NOHZ, sigh!) then the forwarding is done
on an unlocked base. This can lead to corruption of base->clk.
Solution is simple: Invoke the forwarding after the target base is locked.
2) Possible corruption due to jiffies advancing
This is similar to the issue in get_net_timer_interrupt() which was fixed
in the previous patch. jiffies can advance between check and assignement
and therefore advancing base->clk beyond the next expiry value.
So we need to read jiffies into a local variable once and do the checks and
assignment with the local copy.
Fixes: a683f390b93f("timers: Forward the wheel clock whenever possible")
Reported-by: Ashton Holmes <scoopta@gmail.com>
Reported-by: Michael Thayer <michael.thayer@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Michal Necasek <michal.necasek@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: knut.osmundsen@oracle.com
Cc: stable@vger.kernel.org
Cc: stern@rowland.harvard.edu
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161022110552.253640125@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ashton and Michael reported, that kernel versions 4.8 and later suffer from
USB timeouts which are caused by the timer wheel rework.
This is caused by a bug in the base clock forwarding mechanism, which leads
to timers expiring early. The scenario which leads to this is:
run_timers()
while (jiffies >= base->clk) {
collect_expired_timers();
base->clk++;
expire_timers();
}
So base->clk = jiffies + 1. Now the cpu goes idle:
idle()
get_next_timer_interrupt()
nextevt = __next_time_interrupt();
if (time_after(nextevt, base->clk))
base->clk = jiffies;
jiffies has not advanced since run_timers(), so this assignment effectively
decrements base->clk by one.
base->clk is the index into the timer wheel arrays. So let's assume the
following state after the base->clk increment in run_timers():
jiffies = 0
base->clk = 1
A timer gets enqueued with an expiry delta of 63 ticks (which is the case
with the USB timeout and HZ=250) so the resulting bucket index is:
base->clk + delta = 1 + 63 = 64
The timer goes into the first wheel level. The array size is 64 so it ends
up in bucket 0, which is correct as it takes 63 ticks to advance base->clk
to index into bucket 0 again.
If the cpu goes idle before jiffies advance, then the bug in the forwarding
mechanism sets base->clk back to 0, so the next invocation of run_timers()
at the next tick will index into bucket 0 and therefore expire the timer 62
ticks too early.
Instead of blindly setting base->clk to jiffies we must make the forwarding
conditional on jiffies > base->clk, but we cannot use jiffies for this as
we might run into the following issue:
if (time_after(jiffies, base->clk) {
if (time_after(nextevt, base->clk))
base->clk = jiffies;
jiffies can increment between the check and the assigment far enough to
advance beyond nextevt. So we need to use a stable value for checking.
get_next_timer_interrupt() has the basej argument which is the jiffies
value snapshot taken in the calling code. So we can just that.
Thanks to Ashton for bisecting and providing trace data!
Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Reported-by: Ashton Holmes <scoopta@gmail.com>
Reported-by: Michael Thayer <michael.thayer@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Michal Necasek <michal.necasek@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: knut.osmundsen@oracle.com
Cc: stable@vger.kernel.org
Cc: stern@rowland.harvard.edu
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161022110552.175308322@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Linus stumbled over the unlocked modification of the timer expiry value in
mod_timer() which is an optimization for timers which stay in the same
bucket - due to the bucket granularity - despite their expiry time getting
updated.
The optimization itself still makes sense even if we take the lock, because
in case that the bucket stays the same, we avoid the pointless
queue/enqueue dance.
Make the check and the modification of timer->expires protected by the base
lock and shuffle the remaining code around so we can keep the lock held
when we actually have to requeue the timer to a different bucket.
Fixes: f00c0afdfa ("timers: Implement optimization for same expiry time in mod_timer()")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1610241711220.4983@nanos
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Linus noticed that lock_timer_base() lacks a READ_ONCE() for accessing the
timer flags. As a consequence the compiler is allowed to reload the flags
between the initial check for TIMER_MIGRATION and the following timer base
computation and the spin lock of the base.
While this has not been observed (yet), we need to make sure that it never
happens.
Fixes: 0eeda71bc3 ("timer: Replace timer base by a cpu index")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1610241711220.4983@nanos
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
The recent rewrite of the sequencer time accounting using timespec64
in the commit [3915bf2946: ALSA: seq_timer: use monotonic times
internally] introduced a bad regression. Namely, the time reported
back doesn't increase but goes back and forth.
The culprit was obvious: the delta is stored to the result (cur_time =
delta), instead of adding the delta (cur_time += delta)!
Let's fix it.
Fixes: 3915bf2946 ('ALSA: seq_timer: use monotonic times internally')
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=177571
Reported-by: Yves Guillemot <yc.guillemot@wanadoo.fr>
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Some SoC might load the GPIO driver after the I2C driver and
using the I2C bus recovery mechanism via GPIOs. In this case
it is crucial to defer probing if the GPIO request functions
do so, otherwise the I2C driver gets loaded without recovery
mechanisms enabled.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
I2C DesignWare may abort transfer with arbitration lost if I2C slave pulls
SDA down quickly after falling edge of SCL. Reason for this is unknown but
after trial and error it was found this can be avoided by enabling non-zero
SDA RX hold time for the receiver.
By the specification SDA RX hold time extends incoming SDA low to high
transition by n * ic_clk cycles but only when SCL is high. However it
seems to help avoid above faulty arbitration lost error.
Bits 23:16 in IC_SDA_HOLD register define the SDA RX hold time for the
receiver. Be conservative and enable 1 ic_clk cycle long hold time in
case boot firmware hasn't set it up.
Reported-by: Jukka Laitinen <jukka.laitinen@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jukka Laitinen <jukka.laitinen@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Starting with the 8-Series/C220 PCH (Lynx Point), the SMBus
controller includes a SPD EEPROM protection mechanism. Once the SPD
Write Disable bit is set, only reads are allowed to slave addresses
0x50-0x57.
However the legacy implementation of I2C Block Read since the ICH5
looks like a write, and is therefore blocked by the SPD protection
mechanism. This causes the eeprom and at24 drivers to fail.
So assume that I2C Block Read is implemented as an actual read on
these chipsets. I tested it on my Q87 chipset and it seems to work
just fine.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
[wsa: rebased to v4.9-rc2]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBus block command uses the first byte of buffer for the data length.
The dma_buffer should be increased by 1 to avoid the overrun issue.
Reported-by: Phil Endecott <phil_gjouf_endecott@chezphil.org>
Signed-off-by: Hoan Tran <hotran@apm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.
Export the module alias information using the MODULE_DEVICE_TABLE() macro.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.
Export the module alias information using the MODULE_DEVICE_TABLE() macro.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.
Export the module alias information using the MODULE_DEVICE_TABLE() macro.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.
Export the module alias information using the MODULE_DEVICE_TABLE() macro.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The i2c controller used by Freescales iMX processors is the same
hardware module used on Freescales ColdFire family of processors.
We can use the existing i2c-imx driver on ColdFire family members.
Modify the configuration to allow it to be selected when compiling
for ColdFire targets.
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Instantiated I2C device nodes are marked with OF_POPULATE. This was
introduced in 4f001fd301. On unloading, loaded device nodes will of
course be unmarked. The problem are nodes that fail during
initialisation: If a node fails, it won't be unloaded and hence not be
unmarked.
If a I2C driver module is unloaded and reloaded, it will skip nodes that
failed before.
Skip device nodes that are already populated and mark them only in case
of success.
Fixes: 4f001fd301 ("i2c: Mark instantiated device nodes with OF_POPULATE")
Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[wsa: use 14-digit commit sha]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
gcc -Wmaybe-uninitialized detects that quirk_intel_brickland_xeon_ras_cap
uses uninitialized data when CONFIG_PCI is not set:
arch/x86/kernel/quirks.c: In function ‘quirk_intel_brickland_xeon_ras_cap’:
arch/x86/kernel/quirks.c:641:13: error: ‘capid0’ is used uninitialized in this function [-Werror=uninitialized]
However, the function is also not called in this configuration, so we
can avoid the warning by moving the existing #ifdef to cover it as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/20161024153325.2752428-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vince Waver reported the following bug:
WARNING: CPU: 0 PID: 21338 at arch/x86/mm/fault.c:435 vmalloc_fault+0x58/0x1f0
CPU: 0 PID: 21338 Comm: perf_fuzzer Not tainted 4.8.0+ #37
Hardware name: Hewlett-Packard HP Compaq Pro 6305 SFF/1850, BIOS K06 v02.57 08/16/2013
Call Trace:
<NMI> ? dump_stack+0x46/0x59
? __warn+0xd5/0xee
? vmalloc_fault+0x58/0x1f0
? __do_page_fault+0x6d/0x48e
? perf_log_throttle+0xa4/0xf4
? trace_page_fault+0x22/0x30
? __unwind_start+0x28/0x42
? perf_callchain_kernel+0x75/0xac
? get_perf_callchain+0x13a/0x1f0
? perf_callchain+0x6a/0x6c
? perf_prepare_sample+0x71/0x2eb
? perf_event_output_forward+0x1a/0x54
? __default_send_IPI_shortcut+0x10/0x2d
? __perf_event_overflow+0xfb/0x167
? x86_pmu_handle_irq+0x113/0x150
? native_read_msr+0x6/0x34
? perf_event_nmi_handler+0x22/0x39
? perf_ibs_nmi_handler+0x4a/0x51
? perf_event_nmi_handler+0x22/0x39
? nmi_handle+0x4d/0xf0
? perf_ibs_handle_irq+0x3d1/0x3d1
? default_do_nmi+0x3c/0xd5
? do_nmi+0x92/0x102
? end_repeat_nmi+0x1a/0x1e
? entry_SYSCALL_64_after_swapgs+0x12/0x4a
? entry_SYSCALL_64_after_swapgs+0x12/0x4a
? entry_SYSCALL_64_after_swapgs+0x12/0x4a
<EOE> ^A4---[ end trace 632723104d47d31a ]---
BUG: stack guard page was hit at ffffc90008500000 (stack is ffffc900084fc000..ffffc900084fffff)
kernel stack overflow (page fault): 0000 [#1] SMP
...
The NMI hit in the entry code right after setting up the stack pointer
from 'cpu_current_top_of_stack', so the kernel stack was empty. The
'guess' version of __unwind_start() attempted to dereference the "top of
stack" pointer, which is not actually *on* the stack.
Add a check in the guess unwinder to deal with an empty stack. (The
frame pointer unwinder already has such a check.)
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 7c7900f897 ("x86/unwind: Add new unwind interface and implementations")
Link: http://lkml.kernel.org/r/20161024133127.e5evgeebdbohnmpb@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
