Commit Graph

3942 Commits

Author SHA1 Message Date
Anshuman Khandual
78e7c5af08 mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
Currently there are many platforms that dont enable ARCH_HAS_PTE_SPECIAL
but required to define quite similar fallback stubs for special page
table entry helpers such as pte_special() and pte_mkspecial(), as they
get build in generic MM without a config check.  This creates two
generic fallback stub definitions for these helpers, eliminating much
code duplication.

mips platform has a special case where pte_special() and pte_mkspecial()
visibility is wider than what ARCH_HAS_PTE_SPECIAL enablement requires.
This restricts those symbol visibility in order to avoid redefinitions
which is now exposed through this new generic stubs and subsequent build
failure.  arm platform set_pte_at() definition needs to be moved into a
C file just to prevent a build failure.

[anshuman.khandual@arm.com: use defined(CONFIG_ARCH_HAS_PTE_SPECIAL) in mips per Thomas]
  Link: http://lkml.kernel.org/r/1583851924-21603-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guo Ren <guoren@kernel.org>			[csky]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Stafford Horne <shorne@gmail.com>		[openrisc]
Acked-by: Helge Deller <deller@gmx.de>			[parisc]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: http://lkml.kernel.org/r/1583802551-15406-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Anshuman Khandual
c62da0c35d mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Arjun Roy
251a0ffeae mm: bring sparc pte_index() semantics inline with other platforms
pte_index() on platforms other than sparc return a numerical index.  On
sparc, it returns a pte_t*.  This presents an issue for
vm_insert_pages(), which relies on pte_index() to find the offset for a
pte within a pmd, for batched inserts.

This patch:
1. Modifies pte_index() for sparc to return a numerical index, like
   other platforms,
2. Defines pte_entry() for sparc which returns a pte_t*
   (as pte_index() used to),
3. Converts existing sparc callers for pte_index() to use pte_entry().

[sfr@canb.auug.org.au: remove pte_entry and just directly modified pte_offset_kernel instead]
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: David Miller <davem@davemloft.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arjun Roy <arjunroy.kdev@gmail.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Link: http://lkml.kernel.org/r/20200227105045.6b421d9f@canb.auug.org.au
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Linus Torvalds
63bef48fd6 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - a lot more of MM, quite a bit more yet to come: (memcg, pagemap,
   vmalloc, pagealloc, migration, thp, ksm, madvise, virtio,
   userfaultfd, memory-hotplug, shmem, rmap, zswap, zsmalloc, cleanups)

 - various other subsystems (procfs, misc, MAINTAINERS, bitops, lib,
   checkpatch, epoll, binfmt, kallsyms, reiserfs, kmod, gcov, kconfig,
   ubsan, fault-injection, ipc)

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (158 commits)
  ipc/shm.c: make compat_ksys_shmctl() static
  ipc/mqueue.c: fix a brace coding style issue
  lib/Kconfig.debug: fix a typo "capabilitiy" -> "capability"
  ubsan: include bug type in report header
  kasan: unset panic_on_warn before calling panic()
  ubsan: check panic_on_warn
  drivers/misc/lkdtm/bugs.c: add arithmetic overflow and array bounds checks
  ubsan: split "bounds" checker from other options
  ubsan: add trap instrumentation option
  init/Kconfig: clean up ANON_INODES and old IO schedulers options
  kernel/gcov/fs.c: replace zero-length array with flexible-array member
  gcov: gcc_3_4: replace zero-length array with flexible-array member
  gcov: gcc_4_7: replace zero-length array with flexible-array member
  kernel/kmod.c: fix a typo "assuems" -> "assumes"
  reiserfs: clean up several indentation issues
  kallsyms: unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()
  samples/hw_breakpoint: drop use of kallsyms_lookup_name()
  samples/hw_breakpoint: drop HW_BREAKPOINT_R when reporting writes
  fs/binfmt_elf.c: don't free interpreter's ELF pheaders on common path
  fs/binfmt_elf.c: allocate less for static executable
  ...
2020-04-07 14:11:54 -07:00
Linus Torvalds
12782fbe0f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc update from David Miller:
 "A per-device DMA ops conversion for sparc32 by Chrstioph Hellwig"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc32: use per-device dma_ops
2020-04-07 12:26:07 -07:00
Masahiro Yamada
12a5b00a53 sparc,x86: vdso: remove meaningless undefining CONFIG_OPTIMIZE_INLINING
The code, #undef CONFIG_OPTIMIZE_INLINING, is not working as expected
because <linux/compiler_types.h> is parsed before vclock_gettime.c since
28128c61e0 ("kconfig.h: Include compiler types to avoid missed struct
attributes").

Since then, <linux/compiler_types.h> is included really early by using the
'-include' option.  So, you cannot negate the decision of
<linux/compiler_types.h> in this way.

You can confirm it by checking the pre-processed code, like this:

  $ make arch/x86/entry/vdso/vdso32/vclock_gettime.i

There is no difference with/without CONFIG_CC_OPTIMIZE_FOR_SIZE.

It is about two years since 28128c61e0.  Nobody has reported a problem
(or, nobody has even noticed the fact that this code is not working).

It is ugly and unreliable to attempt to undefine a CONFIG option from C
files, and anyway the inlining heuristic is up to the compiler.

Just remove the broken code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: David Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20200220110807.32534-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:42 -07:00
Michal Simek
06e85c7e9a asm-generic: fix unistd_32.h generation format
Generated files are also checked by sparse that's why add newline to
remove sparse (C=1) warning.

The issue was found on Microblaze and reported like this:
./arch/microblaze/include/generated/uapi/asm/unistd_32.h:438:45: warning:
no newline at end of file

Mips and PowerPC have it already but let's align with style used by m68k.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Stefan Asserhall <stefan.asserhall@xilinx.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (xtensa)
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/4d32ab4e1fb2edb691d2e1687e8fb303c09fd023.1581504803.git.michal.simek@xilinx.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:42 -07:00
Linus Torvalds
ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Christoph Hellwig
255a69a94b sparc32: use per-device dma_ops
sparc32 is the last platform making dynamic decisions in
get_arch_dma_ops based on the bus passed in.  Instead set the
iommu dma_ops at iommu probing and propagate them in
of_propagate_archdata, falling back to the NULL ops for the
direct mapping in the Leon or PCI case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-02 18:11:55 -07:00
Linus Torvalds
79f51b7b9c SCSI misc on 20200402
update changing all our txt files to rst ones.  Excluding that, we
 have the usual driver updates (qla2xxx, ufs, lpfc, zfcp, ibmvfc,
 pm80xx, aacraid), a treewide update for scnprintf and some other minor
 updates.  The major core update is Hannes moving functions out of the
 aacraid driver and into the core.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This series has a huge amount of churn because it pulls in Mauro's doc
  update changing all our txt files to rst ones.

  Excluding that, we have the usual driver updates (qla2xxx, ufs, lpfc,
  zfcp, ibmvfc, pm80xx, aacraid), a treewide update for scnprintf and
  some other minor updates.

  The major core change is Hannes moving functions out of the aacraid
  driver and into the core"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (223 commits)
  scsi: aic7xxx: aic97xx: Remove FreeBSD-specific code
  scsi: ufs: Do not rely on prefetched data
  scsi: dc395x: remove dc395x_bios_param
  scsi: libiscsi: Fix error count for active session
  scsi: hpsa: correct race condition in offload enabled
  scsi: message: fusion: Replace zero-length array with flexible-array member
  scsi: qedi: Add PCI shutdown handler support
  scsi: qedi: Add MFW error recovery process
  scsi: ufs: Enable block layer runtime PM for well-known logical units
  scsi: ufs-qcom: Override devfreq parameters
  scsi: ufshcd: Let vendor override devfreq parameters
  scsi: ufshcd: Update the set frequency to devfreq
  scsi: ufs: Resume ufs host before accessing ufs device
  scsi: ufs-mediatek: customize the delay for enabling host
  scsi: ufs: make HCE polling more compact to improve initialization latency
  scsi: ufs: allow custom delay prior to host enabling
  scsi: ufs-mediatek: use common delay function
  scsi: ufs: introduce common and flexible delay function
  scsi: ufs: use an enum for host capabilities
  scsi: ufs: fix uninitialized tx_lanes in ufshcd_disable_tx_lcc()
  ...
2020-04-02 17:03:53 -07:00
Peter Xu
4064b98270 mm: allow VM_FAULT_RETRY for multiple times
The idea comes from a discussion between Linus and Andrea [1].

Before this patch we only allow a page fault to retry once.  We achieved
this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing
handle_mm_fault() the second time.  This was majorly used to avoid
unexpected starvation of the system by looping over forever to handle the
page fault on a single page.  However that should hardly happen, and after
all for each code path to return a VM_FAULT_RETRY we'll first wait for a
condition (during which time we should possibly yield the cpu) to happen
before VM_FAULT_RETRY is really returned.

This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY
flag when we receive VM_FAULT_RETRY.  It means that the page fault handler
now can retry the page fault for multiple times if necessary without the
need to generate another page fault event.  Meanwhile we still keep the
FAULT_FLAG_TRIED flag so page fault handler can still identify whether a
page fault is the first attempt or not.

Then we'll have these combinations of fault flags (only considering
ALLOW_RETRY flag and TRIED flag):

  - ALLOW_RETRY and !TRIED:  this means the page fault allows to
                             retry, and this is the first try

  - ALLOW_RETRY and TRIED:   this means the page fault allows to
                             retry, and this is not the first try

  - !ALLOW_RETRY and !TRIED: this means the page fault does not allow
                             to retry at all

  - !ALLOW_RETRY and TRIED:  this is forbidden and should never be used

In existing code we have multiple places that has taken special care of
the first condition above by checking against (fault_flags &
FAULT_FLAG_ALLOW_RETRY).  This patch introduces a simple helper to detect
the first retry of a page fault by checking against both (fault_flags &
FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now
even the 2nd try will have the ALLOW_RETRY set, then use that helper in
all existing special paths.  One example is in __lock_page_or_retry(), now
we'll drop the mmap_sem only in the first attempt of page fault and we'll
keep it in follow up retries, so old locking behavior will be retained.

This will be a nice enhancement for current code [2] at the same time a
supporting material for the future userfaultfd-writeprotect work, since in
that work there will always be an explicit userfault writeprotect retry
for protected pages, and if that cannot resolve the page fault (e.g., when
userfaultfd-writeprotect is used in conjunction with swapped pages) then
we'll possibly need a 3rd retry of the page fault.  It might also benefit
other potential users who will have similar requirement like userfault
write-protection.

GUP code is not touched yet and will be covered in follow up patch.

Please read the thread below for more information.

[1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/
[2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:30 -07:00
Peter Xu
dde1607248 mm: introduce FAULT_FLAG_DEFAULT
Although there're tons of arch-specific page fault handlers, most of them
are still sharing the same initial value of the page fault flags.  Say,
merely all of the page fault handlers would allow the fault to be retried,
and they also allow the fault to respond to SIGKILL.

Let's define a default value for the fault flags to replace those initial
page fault flags that were copied over.  With this, it'll be far easier to
introduce new fault flag that can be used by all the architectures instead
of touching all the archs.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:29 -07:00
Peter Xu
4ef873226c mm: introduce fault_signal_pending()
For most architectures, we've got a quick path to detect fatal signal
after a handle_mm_fault().  Introduce a helper for that quick path.

It cleans the current codes a bit so we don't need to duplicate the same
check across archs.  More importantly, this will be an unified place that
we handle the signal immediately right after an interrupted page fault, so
it'll be much easier for us if we want to change the behavior of handling
signals later on for all the archs.

Note that currently only part of the archs are using this new helper,
because some archs have their own way to handle signals.  In the follow up
patches, we'll try to apply this helper to all the rest of archs.

Another note is that the "regs" parameter in the new helper is not used
yet.  It'll be used very soon.  Now we kept it in this patch only to avoid
touching all the archs again in the follow up patches.

[peterx@redhat.com: fix sparse warnings]
  Link: http://lkml.kernel.org/r/20200311145921.GD479302@xz-x1
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220155353.8676-4-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:29 -07:00
Masahiro Yamada
630f289b71 asm-generic: make more kernel-space headers mandatory
Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
    arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
    (arch/*/include/asm/*.h) or specifies it as generic-y in
    arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

----------------------------------->8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
	xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
	mandatory=yes

	for arch in $arches
	do
		if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &&
			! [ -f arch/$arch/include/asm/$header ]; then
			mandatory=no
			break
		fi
	done

	if [ "$mandatory" = yes ]; then
		echo "mandatory-y += $header" >> $tmpfile

		for arch in $arches
		do
			sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
		done
	fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile >> include/asm-generic/Kbuild

----------------------------------->8-----------------------------------

One obvious benefit is the diff stat:

 25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe
a1b39bae16

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Linus Torvalds
5b67fbfc32 Kbuild updates for v5.7
[Build system]
 
  - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define
    a fixed set of export symbols for Generic Kernel Image (GKI)
 
  - allow to run 'make dt_binding_check' without .config
 
  - use full schema for checking DT examples in *.yaml files
 
  - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
    sense because we know the produced modules are never loadable
 
  - Remove unused 'AS' variable
 
 [Kconfig]
 
  - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig files
 
  - relax the 'imply' behavior so that symbols implied by y can become m
 
  - make 'imply' obey 'depends on' in order to make 'imply' really weak
 
 [Misc]
 
  - add documentation on building the kernel with Clang/LLVM
 
  - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()
 
  - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n
 
  - various script and Makefile cleanups
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Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "Build system:

   - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
     fixed set of export symbols for Generic Kernel Image (GKI)

   - allow to run 'make dt_binding_check' without .config

   - use full schema for checking DT examples in *.yaml files

   - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
     sense because we know the produced modules are never loadable

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

   - relax the 'imply' behavior so that symbols implied by 'y' can
     become 'm'

   - make 'imply' obey 'depends on' in order to make 'imply' really weak

  Misc:

   - add documentation on building the kernel with Clang/LLVM

   - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()

   - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...
2020-03-31 16:03:39 -07:00
Linus Torvalds
336622e9fc NOHZ full updates:
- Remove TIF_NOHZ from 3 architectures
 
     These architectures use a static key to decide whether context tracking
     needs to be invoked and the TIF_NOHZ flag just causes a pointless
     slowpath execution for nothing.
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Merge tag 'timers-nohz-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull NOHZ update from Thomas Gleixner:
 "Remove TIF_NOHZ from three architectures

  These architectures use a static key to decide whether context
  tracking needs to be invoked and the TIF_NOHZ flag just causes a
  pointless slowpath execution for nothing"

* tag 'timers-nohz-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm64: Remove TIF_NOHZ
  arm: Remove TIF_NOHZ
  x86: Remove TIF_NOHZ
  context-tracking: Introduce CONFIG_HAVE_TIF_NOHZ
  x86/entry: Remove _TIF_NOHZ from _TIF_WORK_SYSCALL_ENTRY
2020-03-30 18:29:05 -07:00
Linus Torvalds
992a1a3b45 CPU (hotplug) updates:
- Support for locked CSD objects in smp_call_function_single_async()
     which allows to simplify callsites in the scheduler core and MIPS
 
   - Treewide consolidation of CPU hotplug functions which ensures the
     consistency between the sysfs interface and kernel state. The low level
     functions cpu_up/down() are now confined to the core code and not
     longer accessible from random code.
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Merge tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core SMP updates from Thomas Gleixner:
 "CPU (hotplug) updates:

   - Support for locked CSD objects in smp_call_function_single_async()
     which allows to simplify callsites in the scheduler core and MIPS

   - Treewide consolidation of CPU hotplug functions which ensures the
     consistency between the sysfs interface and kernel state. The low
     level functions cpu_up/down() are now confined to the core code and
     not longer accessible from random code"

* tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus()
  cpu/hotplug: Hide cpu_up/down()
  cpu/hotplug: Move bringup of secondary CPUs out of smp_init()
  torture: Replace cpu_up/down() with add/remove_cpu()
  firmware: psci: Replace cpu_up/down() with add/remove_cpu()
  xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()
  parisc: Replace cpu_up/down() with add/remove_cpu()
  sparc: Replace cpu_up/down() with add/remove_cpu()
  powerpc: Replace cpu_up/down() with add/remove_cpu()
  x86/smp: Replace cpu_up/down() with add/remove_cpu()
  arm64: hibernate: Use bringup_hibernate_cpu()
  cpu/hotplug: Provide bringup_hibernate_cpu()
  arm64: Use reboot_cpu instead of hardconding it to 0
  arm64: Don't use disable_nonboot_cpus()
  ARM: Use reboot_cpu instead of hardcoding it to 0
  ARM: Don't use disable_nonboot_cpus()
  ia64: Replace cpu_down() with smp_shutdown_nonboot_cpus()
  cpu/hotplug: Create a new function to shutdown nonboot cpus
  cpu/hotplug: Add new {add,remove}_cpu() functions
  sched/core: Remove rq.hrtick_csd_pending
  ...
2020-03-30 18:06:39 -07:00
Al Viro
dc88588990 [parisc, s390, sparc64] no need for access_ok() in futex handling
access_ok() is always true on those

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-27 23:58:52 -04:00
Al Viro
a08971e948 futex: arch_futex_atomic_op_inuser() calling conventions change
Move access_ok() in and pagefault_enable()/pagefault_disable() out.
Mechanical conversion only - some instances don't really need
a separate access_ok() at all (e.g. the ones only using
get_user()/put_user(), or architectures where access_ok()
is always true); we'll deal with that in followups.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-27 23:58:51 -04:00
Qais Yousef
7f6707a204 sparc: Replace cpu_up/down() with add/remove_cpu()
The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01dd ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.

This also prepares to make cpu_up/down() a private interface of the CPU
subsystem.

Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Link: https://lkml.kernel.org/r/20200323135110.30522-12-qais.yousef@arm.com
2020-03-25 12:59:36 +01:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Masahiro Yamada
51e4064179 sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
Prior to commit 70a6fcf328 ("[sparc] unify 32bit and 64bit string.h"),
__HAVE_ARCH_STRLEN was defined in both of string_32.h and string_64.h

It did not unify __HAVE_ARCH_STRLEN, but deleted it from string_32.h

This issue was reported by the kbuild test robot in the trial of
forcible linking of $(lib-y) to vmlinux.

Fixes: 70a6fcf328 ("[sparc] unify 32bit and 64bit string.h")
Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
2020-03-25 10:19:43 +09:00
Masahiro Yamada
2a86f66121 kbuild: use KBUILD_DEFCONFIG as the fallback for DEFCONFIG_LIST
Most of the Kconfig commands (except defconfig and all*config) read
the .config file as a base set of CONFIG options.

When it does not exist, the files in DEFCONFIG_LIST are searched in
this order and loaded if found.

I do not see much sense in the last two lines in DEFCONFIG_LIST.

[1] ARCH_DEFCONFIG

The entry for DEFCONFIG_LIST is guarded by 'depends on !UML'. So, the
ARCH_DEFCONFIG definition in arch/x86/um/Kconfig is meaningless.

arch/{sh,sparc,x86}/Kconfig define ARCH_DEFCONFIG depending on 32 or
64 bit variant symbols. This is a little bit strange; ARCH_DEFCONFIG
should be a fixed string because the base config file is loaded before
the symbol evaluation stage.

Using KBUILD_DEFCONFIG makes more sense because it is fixed before
Kconfig is invoked. Fortunately, arch/{sh,sparc,x86}/Makefile define it
in the same way, and it works as expected. Hence, replace ARCH_DEFCONFIG
with "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)".

[2] arch/$(ARCH)/defconfig

This file path is no longer valid. The defconfig files are always located
in the arch configs/ directories.

  $ find arch -name defconfig | sort
  arch/alpha/configs/defconfig
  arch/arm64/configs/defconfig
  arch/csky/configs/defconfig
  arch/nds32/configs/defconfig
  arch/riscv/configs/defconfig
  arch/s390/configs/defconfig
  arch/unicore32/configs/defconfig

The path arch/*/configs/defconfig is already covered by
"arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)". So, this file path is
not necessary.

I moved the default KBUILD_DEFCONFIG to the top Makefile. Otherwise,
the 7 architectures listed above would end up with endless loop of
syncconfig.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-03 20:49:21 +09:00
Diego Elio Pettenò
679b2ec8e0 scsi: sr: remove references to BLK_DEV_SR_VENDOR, leave it enabled
This kernel configuration is basically enabling/disabling sr driver quirks
detection. While these quirks are for fairly rare devices (very old CD
burners, and a glucometer), the additional detection of these models is a
very minimal amount of code.

The logic behind the quirks is always built into the sr driver.

This also removes the config from all the defconfig files that are enabling
this already.

Link: https://lore.kernel.org/r/20200223191144.726-1-flameeyes@flameeyes.com
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-02-24 14:59:01 -05:00
Frederic Weisbecker
490f561b78 context-tracking: Introduce CONFIG_HAVE_TIF_NOHZ
A few archs (x86, arm, arm64) don't rely anymore on TIF_NOHZ to call
into context tracking on user entry/exit but instead use static keys
(or not) to optimize those calls. Ideally every arch should migrate to
that behaviour in the long run.

Settle a config option to let those archs remove their TIF_NOHZ
definitions.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David S. Miller <davem@davemloft.net>
2020-02-14 16:05:04 +01:00
Linus Torvalds
89a47dd1af Kbuild updates for v5.6 (2nd)
- fix randconfig to generate a sane .config
 
  - rename hostprogs-y / always to hostprogs / always-y, which are
    more natual syntax.
 
  - optimize scripts/kallsyms
 
  - fix yes2modconfig and mod2yesconfig
 
  - make multiple directory targets ('make foo/ bar/') work
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Merge tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - fix randconfig to generate a sane .config

 - rename hostprogs-y / always to hostprogs / always-y, which are more
   natual syntax.

 - optimize scripts/kallsyms

 - fix yes2modconfig and mod2yesconfig

 - make multiple directory targets ('make foo/ bar/') work

* tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: make multiple directory targets work
  kconfig: Invalidate all symbols after changing to y or m.
  kallsyms: fix type of kallsyms_token_table[]
  scripts/kallsyms: change table to store (strcut sym_entry *)
  scripts/kallsyms: rename local variables in read_symbol()
  kbuild: rename hostprogs-y/always to hostprogs/always-y
  kbuild: fix the document to use extra-y for vmlinux.lds
  kconfig: fix broken dependency in randconfig-generated .config
2020-02-09 16:05:50 -08:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Peter Zijlstra
ff2e6d7259 asm-generic/tlb: rename HAVE_RCU_TABLE_FREE
Towards a more consistent naming scheme.

[akpm@linux-foundation.org: fix sparc64 Kconfig]
Link: http://lkml.kernel.org/r/20200116064531.483522-7-aneesh.kumar@linux.ibm.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Peter Zijlstra
0ed1325967 mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush
Architectures for which we have hardware walkers of Linux page table
should flush TLB on mmu gather batch allocation failures and batch flush.
Some architectures like POWER supports multiple translation modes (hash
and radix) and in the case of POWER only radix translation mode needs the
above TLBI.  This is because for hash translation mode kernel wants to
avoid this extra flush since there are no hardware walkers of linux page
table.  With radix translation, the hardware also walks linux page table
and with that, kernel needs to make sure to TLB invalidate page walk cache
before page table pages are freed.

More details in commit d86564a2f0 ("mm/tlb, x86/mm: Support invalidating
TLB caches for RCU_TABLE_FREE")

The changes to sparc are to make sure we keep the old behavior since we
are now removing HAVE_RCU_TABLE_NO_INVALIDATE.  The default value for
tlb_needs_table_invalidate is to always force an invalidate and sparc can
avoid the table invalidate.  Hence we define tlb_needs_table_invalidate to
false for sparc architecture.

Link: http://lkml.kernel.org/r/20200116064531.483522-3-aneesh.kumar@linux.ibm.com
Fixes: a46cc7a90f ("powerpc/mm/radix: Improve TLB/PWC flushes")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Cc: <stable@vger.kernel.org>	[4.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Steven Price
8094249358 sparc: mm: add p?d_leaf() definitions
walk_page_range() is going to be allowed to walk page tables other than
those of user space.  For this it needs to know when it has reached a
'leaf' entry in the page tables.  This information is provided by the
p?d_leaf() functions/macros.

For sparc 64 bit, pmd_large() and pud_large() are already provided, so add
macros to provide the p?d_leaf names required by the generic code.

Link: http://lkml.kernel.org/r/20191218162402.45610-10-steven.price@arm.com
Signed-off-by: Steven Price <steven.price@arm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: "Liang, Kan" <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zong Li <zong.li@sifive.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:24 +00:00
Masahiro Yamada
5f2fb52fac kbuild: rename hostprogs-y/always to hostprogs/always-y
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-04 01:53:07 +09:00
Arnd Bergmann
11648b8339 sparc64: fix adjtimex regression
Anatoly Pugachev reported one of the y2038 patches to introduce
a fatal bug from a stupid typo:

[   96.384129] watchdog: BUG: soft lockup - CPU#8 stuck for 22s!
...
[   96.385624]  [0000000000652ca4] handle_mm_fault+0x84/0x320
[   96.385668]  [0000000000b6f2bc] do_sparc64_fault+0x43c/0x820
[   96.385720]  [0000000000407754] sparc64_realfault_common+0x10/0x20
[   96.385769]  [000000000042fa28] __do_sys_sparc_clock_adjtime+0x28/0x80
[   96.385819]  [00000000004307f0] sys_sparc_clock_adjtime+0x10/0x20
[   96.385866]  [0000000000406294] linux_sparc_syscall+0x34/0x44

Fix the code to dereference the correct pointer again.

Reported-by: Anatoly Pugachev <matorola@gmail.com>
Tested-by: Anatoly Pugachev <matorola@gmail.com>
Fixes: 251ec1c159 ("y2038: sparc: remove use of struct timex")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-02 11:54:41 +01:00
Linus Torvalds
9ca4c6429f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc updates from David Miller:

 1) Add a proper .exit.data section.

 2) Fix ipc64_perm type definition, from Arnd Bergmann.

 3) Support folded p4d page tables on sparc64, from Mike Rapport.

 4) Remove uses of struct timex, also from Arnd Bergmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  y2038: sparc: remove use of struct timex
  sparc64: add support for folded p4d page tables
  sparc/console: kill off obsolete declarations
  sparc32: fix struct ipc64_perm type definition
  sparc32, leon: Stop adding vendor and device id to prom ambapp path components
  sparc: Add .exit.data section.
  sparc: remove unneeded uapi/asm/statfs.h
2020-01-30 07:36:43 -08:00
Arnd Bergmann
d68712ee35 y2038: sparc: remove use of struct timex
'struct timex' is one of the last users of 'struct timeval' and is
only referenced in one place in the kernel any more, to convert the
user space timex into the kernel-internal version on sparc64, with a
different tv_usec member type.

As a preparation for hiding the time_t definition and everything
using that in the kernel, change the implementation once more
to only convert the timeval member, and then enclose the
struct definition in an #ifdef.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Julian Calaby <julian.calaby@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-30 11:14:28 +01:00
Mike Rapoport
5637bc5048 sparc64: add support for folded p4d page tables
Implement primitives necessary for the 4th level folding, add walks of p4d
level where appropriate and replace 5level-fixup.h with pgtable-nop4d.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-30 11:14:28 +01:00
Linus Torvalds
83fa805bcb threads-v5.6
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Merge tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull thread management updates from Christian Brauner:
 "Sargun Dhillon over the last cycle has worked on the pidfd_getfd()
  syscall.

  This syscall allows for the retrieval of file descriptors of a process
  based on its pidfd. A task needs to have ptrace_may_access()
  permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and
  Andy) on the target.

  One of the main use-cases is in combination with seccomp's user
  notification feature. As a reminder, seccomp's user notification
  feature was made available in v5.0. It allows a task to retrieve a
  file descriptor for its seccomp filter. The file descriptor is usually
  handed of to a more privileged supervising process. The supervisor can
  then listen for syscall events caught by the seccomp filter of the
  supervisee and perform actions in lieu of the supervisee, usually
  emulating syscalls. pidfd_getfd() is needed to expand its uses.

  There are currently two major users that wait on pidfd_getfd() and one
  future user:

   - Netflix, Sargun said, is working on a service mesh where users
     should be able to connect to a dns-based VIP. When a user connects
     to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be
     redirected to an envoy process. This service mesh uses seccomp user
     notifications and pidfd to intercept all connect calls and instead
     of connecting them to 1.2.3.4:80 connects them to e.g.
     127.0.0.1:8080.

   - LXD uses the seccomp notifier heavily to intercept and emulate
     mknod() and mount() syscalls for unprivileged containers/processes.
     With pidfd_getfd() more uses-cases e.g. bridging socket connections
     will be possible.

   - The patchset has also seen some interest from the browser corner.
     Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a
     broker process. In the future glibc will start blocking all signals
     during dlopen() rendering this type of sandbox impossible. Hence,
     in the future Firefox will switch to a seccomp-user-nofication
     based sandbox which also makes use of file descriptor retrieval.
     The thread for this can be found at
     https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html

  With pidfd_getfd() it is e.g. possible to bridge socket connections
  for the supervisee (binding to a privileged port) and taking actions
  on file descriptors on behalf of the supervisee in general.

  Sargun's first version was using an ioctl on pidfds but various people
  pushed for it to be a proper syscall which he duely implemented as
  well over various review cycles. Selftests are of course included.
  I've also added instructions how to deal with merge conflicts below.

  There's also a small fix coming from the kernel mentee project to
  correctly annotate struct sighand_struct with __rcu to fix various
  sparse warnings. We've received a few more such fixes and even though
  they are mostly trivial I've decided to postpone them until after -rc1
  since they came in rather late and I don't want to risk introducing
  build warnings.

  Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is
  needed to avoid allocation recursions triggerable by storage drivers
  that have userspace parts that run in the IO path (e.g. dm-multipath,
  iscsi, etc). These allocation recursions deadlock the device.

  The new prctl() allows such privileged userspace components to avoid
  allocation recursions by setting the PF_MEMALLOC_NOIO and
  PF_LESS_THROTTLE flags. The patch carries the necessary acks from the
  relevant maintainers and is routed here as part of prctl()
  thread-management."

* tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim
  sched.h: Annotate sighand_struct with __rcu
  test: Add test for pidfd getfd
  arch: wire up pidfd_getfd syscall
  pid: Implement pidfd_getfd syscall
  vfs, fdtable: Add fget_task helper
2020-01-29 19:38:34 -08:00
Linus Torvalds
33c84e89ab SCSI misc on 20200129
This series is slightly unusual because it includes Arnd's compat
 ioctl tree here:
 
 1c46a2cf2d Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue
 
 Excluding Arnd's changes, this is mostly an update of the usual
 drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.  There
 are a couple of core and base updates around error propagation and
 atomicity in the attribute container base we use for the SCSI
 transport classes.  The rest is minor changes and updates.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This series is slightly unusual because it includes Arnd's compat
  ioctl tree here:

    1c46a2cf2d Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue

  Excluding Arnd's changes, this is mostly an update of the usual
  drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.

  There are a couple of core and base updates around error propagation
  and atomicity in the attribute container base we use for the SCSI
  transport classes.

  The rest is minor changes and updates"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits)
  scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask
  scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity
  scsi: hisi_sas: Modify the file permissions of trigger_dump to write only
  scsi: hisi_sas: Replace magic number when handle channel interrupt
  scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock
  scsi: hisi_sas: use threaded irq to process CQ interrupts
  scsi: ufs: Use UFS device indicated maximum LU number
  scsi: ufs: Add max_lu_supported in struct ufs_dev_info
  scsi: ufs: Delete is_init_prefetch from struct ufs_hba
  scsi: ufs: Inline two functions into their callers
  scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init()
  scsi: ufs: Split ufshcd_probe_hba() based on its called flow
  scsi: ufs: Delete struct ufs_dev_desc
  scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails
  scsi: ufs-mediatek: enable low-power mode for hibern8 state
  scsi: ufs: export some functions for vendor usage
  scsi: ufs-mediatek: add dbg_register_dump implementation
  scsi: qla2xxx: Fix a NULL pointer dereference in an error path
  scsi: qla1280: Make checking for 64bit support consistent
  scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1
  ...
2020-01-29 18:16:16 -08:00
Linus Torvalds
22b17db4ea y2038: core, driver and file system changes
These are updates to device drivers and file systems that for some reason
 or another were not included in the kernel in the previous y2038 series.
 
 I've gone through all users of time_t again to make sure the kernel is
 in a long-term maintainable state, replacing all remaining references
 to time_t with safe alternatives.
 
 Some related parts of the series were picked up into the nfsd, xfs,
 alsa and v4l2 trees. A final set of patches in linux-mm removes the now
 unused time_t/timeval/timespec types and helper functions after all five
 branches are merged for linux-5.6, ensuring that no new users get merged.
 
 As a result, linux-5.6, or my backport of the patches to 5.4 [1], should
 be the first release that can serve as a base for a 32-bit system designed
 to run beyond year 2038, with a few remaining caveats:
 
 - All user space must be compiled with a 64-bit time_t, which will be
   supported in the coming musl-1.2 and glibc-2.32 releases, along with
   installed kernel headers from linux-5.6 or higher.
 
 - Applications that use the system call interfaces directly need to be
   ported to use the time64 syscalls added in linux-5.1 in place of the
   existing system calls. This impacts most users of futex() and seccomp()
   as well as programming languages that have their own runtime environment
   not based on libc.
 
 - Applications that use a private copy of kernel uapi header files or
   their contents may need to update to the linux-5.6 version, in
   particular for sound/asound.h, xfs/xfs_fs.h, linux/input.h,
   linux/elfcore.h, linux/sockios.h, linux/timex.h and linux/can/bcm.h.
 
 - A few remaining interfaces cannot be changed to pass a 64-bit time_t
   in a compatible way, so they must be configured to use CLOCK_MONOTONIC
   times or (with a y2106 problem) unsigned 32-bit timestamps. Most
   importantly this impacts all users of 'struct input_event'.
 
 - All y2038 problems that are present on 64-bit machines also apply to
   32-bit machines. In particular this affects file systems with on-disk
   timestamps using signed 32-bit seconds: ext4 with ext3-style small
   inodes, ext2, xfs (to be fixed soon) and ufs.
 
 Changes since v1 [2]:
 
 - Add Acks I received
 - Rebase to v5.5-rc1, dropping patches that got merged already
 - Add NFS, XFS and the final three patches from another series
 - Rewrite etnaviv patches
 - Add one late revert to avoid an etnaviv regression
 
 [1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-endgame
 [2] https://lore.kernel.org/lkml/20191108213257.3097633-1-arnd@arndb.de/
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Merge tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 updates from Arnd Bergmann:
 "Core, driver and file system changes

  These are updates to device drivers and file systems that for some
  reason or another were not included in the kernel in the previous
  y2038 series.

  I've gone through all users of time_t again to make sure the kernel is
  in a long-term maintainable state, replacing all remaining references
  to time_t with safe alternatives.

  Some related parts of the series were picked up into the nfsd, xfs,
  alsa and v4l2 trees. A final set of patches in linux-mm removes the
  now unused time_t/timeval/timespec types and helper functions after
  all five branches are merged for linux-5.6, ensuring that no new users
  get merged.

  As a result, linux-5.6, or my backport of the patches to 5.4 [1],
  should be the first release that can serve as a base for a 32-bit
  system designed to run beyond year 2038, with a few remaining caveats:

   - All user space must be compiled with a 64-bit time_t, which will be
     supported in the coming musl-1.2 and glibc-2.32 releases, along
     with installed kernel headers from linux-5.6 or higher.

   - Applications that use the system call interfaces directly need to
     be ported to use the time64 syscalls added in linux-5.1 in place of
     the existing system calls. This impacts most users of futex() and
     seccomp() as well as programming languages that have their own
     runtime environment not based on libc.

   - Applications that use a private copy of kernel uapi header files or
     their contents may need to update to the linux-5.6 version, in
     particular for sound/asound.h, xfs/xfs_fs.h, linux/input.h,
     linux/elfcore.h, linux/sockios.h, linux/timex.h and
     linux/can/bcm.h.

   - A few remaining interfaces cannot be changed to pass a 64-bit
     time_t in a compatible way, so they must be configured to use
     CLOCK_MONOTONIC times or (with a y2106 problem) unsigned 32-bit
     timestamps. Most importantly this impacts all users of 'struct
     input_event'.

   - All y2038 problems that are present on 64-bit machines also apply
     to 32-bit machines. In particular this affects file systems with
     on-disk timestamps using signed 32-bit seconds: ext4 with
     ext3-style small inodes, ext2, xfs (to be fixed soon) and ufs"

[1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-endgame

* tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (21 commits)
  Revert "drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC"
  y2038: sh: remove timeval/timespec usage from headers
  y2038: sparc: remove use of struct timex
  y2038: rename itimerval to __kernel_old_itimerval
  y2038: remove obsolete jiffies conversion functions
  nfs: fscache: use timespec64 in inode auxdata
  nfs: fix timstamp debug prints
  nfs: use time64_t internally
  sunrpc: convert to time64_t for expiry
  drm/etnaviv: avoid deprecated timespec
  drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC
  drm/msm: avoid using 'timespec'
  hfs/hfsplus: use 64-bit inode timestamps
  hostfs: pass 64-bit timestamps to/from user space
  packet: clarify timestamp overflow
  tsacct: add 64-bit btime field
  acct: stop using get_seconds()
  um: ubd: use 64-bit time_t where possible
  xtensa: ISS: avoid struct timeval
  dlm: use SO_SNDTIMEO_NEW instead of SO_SNDTIMEO_OLD
  ...
2020-01-29 14:55:47 -08:00
Linus Torvalds
6aee4badd8 Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull openat2 support from Al Viro:
 "This is the openat2() series from Aleksa Sarai.

  I'm afraid that the rest of namei stuff will have to wait - it got
  zero review the last time I'd posted #work.namei, and there had been a
  leak in the posted series I'd caught only last weekend. I was going to
  repost it on Monday, but the window opened and the odds of getting any
  review during that... Oh, well.

  Anyway, openat2 part should be ready; that _did_ get sane amount of
  review and public testing, so here it comes"

From Aleksa's description of the series:
 "For a very long time, extending openat(2) with new features has been
  incredibly frustrating. This stems from the fact that openat(2) is
  possibly the most famous counter-example to the mantra "don't silently
  accept garbage from userspace" -- it doesn't check whether unknown
  flags are present[1].

  This means that (generally) the addition of new flags to openat(2) has
  been fraught with backwards-compatibility issues (O_TMPFILE has to be
  defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
  kernels gave errors, since it's insecure to silently ignore the
  flag[2]). All new security-related flags therefore have a tough road
  to being added to openat(2).

  Furthermore, the need for some sort of control over VFS's path
  resolution (to avoid malicious paths resulting in inadvertent
  breakouts) has been a very long-standing desire of many userspace
  applications.

  This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
  (which was a variant of David Drysdale's O_BENEATH patchset[4] which
  was a spin-off of the Capsicum project[5]) with a few additions and
  changes made based on the previous discussion within [6] as well as
  others I felt were useful.

  In line with the conclusions of the original discussion of
  AT_NO_JUMPS, the flag has been split up into separate flags. However,
  instead of being an openat(2) flag it is provided through a new
  syscall openat2(2) which provides several other improvements to the
  openat(2) interface (see the patch description for more details). The
  following new LOOKUP_* flags are added:

  LOOKUP_NO_XDEV:

     Blocks all mountpoint crossings (upwards, downwards, or through
     absolute links). Absolute pathnames alone in openat(2) do not
     trigger this. Magic-link traversal which implies a vfsmount jump is
     also blocked (though magic-link jumps on the same vfsmount are
     permitted).

  LOOKUP_NO_MAGICLINKS:

     Blocks resolution through /proc/$pid/fd-style links. This is done
     by blocking the usage of nd_jump_link() during resolution in a
     filesystem. The term "magic-links" is used to match with the only
     reference to these links in Documentation/, but I'm happy to change
     the name.

     It should be noted that this is different to the scope of
     ~LOOKUP_FOLLOW in that it applies to all path components. However,
     you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
     will *not* fail (assuming that no parent component was a
     magic-link), and you will have an fd for the magic-link.

     In order to correctly detect magic-links, the introduction of a new
     LOOKUP_MAGICLINK_JUMPED state flag was required.

  LOOKUP_BENEATH:

     Disallows escapes to outside the starting dirfd's
     tree, using techniques such as ".." or absolute links. Absolute
     paths in openat(2) are also disallowed.

     Conceptually this flag is to ensure you "stay below" a certain
     point in the filesystem tree -- but this requires some additional
     to protect against various races that would allow escape using
     "..".

     Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
     can trivially beam you around the filesystem (breaking the
     protection). In future, there might be similar safety checks done
     as in LOOKUP_IN_ROOT, but that requires more discussion.

  In addition, two new flags are added that expand on the above ideas:

  LOOKUP_NO_SYMLINKS:

     Does what it says on the tin. No symlink resolution is allowed at
     all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
     can still be used with NOFOLLOW to open an fd for the symlink as
     long as no parent path had a symlink component.

  LOOKUP_IN_ROOT:

     This is an extension of LOOKUP_BENEATH that, rather than blocking
     attempts to move past the root, forces all such movements to be
     scoped to the starting point. This provides chroot(2)-like
     protection but without the cost of a chroot(2) for each filesystem
     operation, as well as being safe against race attacks that
     chroot(2) is not.

     If a race is detected (as with LOOKUP_BENEATH) then an error is
     generated, and similar to LOOKUP_BENEATH it is not permitted to
     cross magic-links with LOOKUP_IN_ROOT.

     The primary need for this is from container runtimes, which
     currently need to do symlink scoping in userspace[7] when opening
     paths in a potentially malicious container.

     There is a long list of CVEs that could have bene mitigated by
     having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
     CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
     few).

  In order to make all of the above more usable, I'm working on
  libpathrs[8] which is a C-friendly library for safe path resolution.
  It features a userspace-emulated backend if the kernel doesn't support
  openat2(2). Hopefully we can get userspace to switch to using it, and
  thus get openat2(2) support for free once it's ready.

  Future work would include implementing things like
  RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
  programs to be sure they don't hit DoSes though stale NFS handles)"

* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Documentation: path-lookup: include new LOOKUP flags
  selftests: add openat2(2) selftests
  open: introduce openat2(2) syscall
  namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
  namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
  namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
  namei: LOOKUP_NO_XDEV: block mountpoint crossing
  namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
  namei: LOOKUP_NO_SYMLINKS: block symlink resolution
  namei: allow set_root() to produce errors
  namei: allow nd_jump_link() to produce errors
  nsfs: clean-up ns_get_path() signature to return int
  namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-29 11:20:24 -08:00
Linus Torvalds
ca9b5b6283 TTY/Serial driver updates for 5.6-rc1
Here are the big set of tty and serial driver updates for 5.6-rc1
 
 Included in here are:
 	- dummy_con cleanups (touches lots of arch code)
 	- sysrq logic cleanups (touches lots of serial drivers)
 	- samsung driver fixes (wasn't really being built)
 	- conmakeshash move to tty subdir out of scripts
 	- lots of small tty/serial driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here are the big set of tty and serial driver updates for 5.6-rc1

  Included in here are:
   - dummy_con cleanups (touches lots of arch code)
   - sysrq logic cleanups (touches lots of serial drivers)
   - samsung driver fixes (wasn't really being built)
   - conmakeshash move to tty subdir out of scripts
   - lots of small tty/serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: n_hdlc: Use flexible-array member and struct_size() helper
  tty: baudrate: SPARC supports few more baud rates
  tty: baudrate: Synchronise baud_table[] and baud_bits[]
  tty: serial: meson_uart: Add support for kernel debugger
  serial: imx: fix a race condition in receive path
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial_core: Remove unused member in uart_port
  vt: Correct comment documenting do_take_over_console()
  vt: Delete comment referencing non-existent unbind_con_driver()
  arch/xtensa/setup: Drop dummy_con initialization
  arch/x86/setup: Drop dummy_con initialization
  arch/unicore32/setup: Drop dummy_con initialization
  arch/sparc/setup: Drop dummy_con initialization
  arch/sh/setup: Drop dummy_con initialization
  arch/s390/setup: Drop dummy_con initialization
  ...
2020-01-29 10:13:27 -08:00
Linus Torvalds
a78208e243 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Removed CRYPTO_TFM_RES flags
   - Extended spawn grabbing to all algorithm types
   - Moved hash descsize verification into API code

  Algorithms:
   - Fixed recursive pcrypt dead-lock
   - Added new 32 and 64-bit generic versions of poly1305
   - Added cryptogams implementation of x86/poly1305

  Drivers:
   - Added support for i.MX8M Mini in caam
   - Added support for i.MX8M Nano in caam
   - Added support for i.MX8M Plus in caam
   - Added support for A33 variant of SS in sun4i-ss
   - Added TEE support for Raven Ridge in ccp
   - Added in-kernel API to submit TEE commands in ccp
   - Added AMD-TEE driver
   - Added support for BCM2711 in iproc-rng200
   - Added support for AES256-GCM based ciphers for chtls
   - Added aead support on SEC2 in hisilicon"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (244 commits)
  crypto: arm/chacha - fix build failured when kernel mode NEON is disabled
  crypto: caam - add support for i.MX8M Plus
  crypto: x86/poly1305 - emit does base conversion itself
  crypto: hisilicon - fix spelling mistake "disgest" -> "digest"
  crypto: chacha20poly1305 - add back missing test vectors and test chunking
  crypto: x86/poly1305 - fix .gitignore typo
  tee: fix memory allocation failure checks on drv_data and amdtee
  crypto: ccree - erase unneeded inline funcs
  crypto: ccree - make cc_pm_put_suspend() void
  crypto: ccree - split overloaded usage of irq field
  crypto: ccree - fix PM race condition
  crypto: ccree - fix FDE descriptor sequence
  crypto: ccree - cc_do_send_request() is void func
  crypto: ccree - fix pm wrongful error reporting
  crypto: ccree - turn errors to debug msgs
  crypto: ccree - fix AEAD decrypt auth fail
  crypto: ccree - fix typo in comment
  crypto: ccree - fix typos in error msgs
  crypto: atmel-{aes,sha,tdes} - Retire crypto_platform_data
  crypto: x86/sha - Eliminate casts on asm implementations
  ...
2020-01-28 15:38:56 -08:00
Linus Torvalds
c677124e63 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "These were the main changes in this cycle:

   - More -rt motivated separation of CONFIG_PREEMPT and
     CONFIG_PREEMPTION.

   - Add more low level scheduling topology sanity checks and warnings
     to filter out nonsensical topologies that break scheduling.

   - Extend uclamp constraints to influence wakeup CPU placement

   - Make the RT scheduler more aware of asymmetric topologies and CPU
     capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y

   - Make idle CPU selection more consistent

   - Various fixes, smaller cleanups, updates and enhancements - please
     see the git log for details"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  sched/fair: Define sched_idle_cpu() only for SMP configurations
  sched/topology: Assert non-NUMA topology masks don't (partially) overlap
  idle: fix spelling mistake "iterrupts" -> "interrupts"
  sched/fair: Remove redundant call to cpufreq_update_util()
  sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
  sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
  sched/fair: calculate delta runnable load only when it's needed
  sched/cputime: move rq parameter in irqtime_account_process_tick
  stop_machine: Make stop_cpus() static
  sched/debug: Reset watchdog on all CPUs while processing sysrq-t
  sched/core: Fix size of rq::uclamp initialization
  sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
  sched/fair: Load balance aggressively for SCHED_IDLE CPUs
  sched/fair : Improve update_sd_pick_busiest for spare capacity case
  watchdog: Remove soft_lockup_hrtimer_cnt and related code
  sched/rt: Make RT capacity-aware
  sched/fair: Make EAS wakeup placement consider uclamp restrictions
  sched/fair: Make task_fits_capacity() consider uclamp restrictions
  sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
  sched/uclamp: Make uclamp util helpers use and return UL values
  ...
2020-01-28 10:07:09 -08:00
Linus Torvalds
634cd4b6af Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cleanup of the GOP [graphics output] handling code in the EFI stub

   - Complete refactoring of the mixed mode handling in the x86 EFI stub

   - Overhaul of the x86 EFI boot/runtime code

   - Increase robustness for mixed mode code

   - Add the ability to disable DMA at the root port level in the EFI
     stub

   - Get rid of RWX mappings in the EFI memory map and page tables,
     where possible

   - Move the support code for the old EFI memory mapping style into its
     only user, the SGI UV1+ support code.

   - plus misc fixes, updates, smaller cleanups.

  ... and due to interactions with the RWX changes, another round of PAT
  cleanups make a guest appearance via the EFI tree - with no side
  effects intended"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  efi/x86: Disable instrumentation in the EFI runtime handling code
  efi/libstub/x86: Fix EFI server boot failure
  efi/x86: Disallow efi=old_map in mixed mode
  x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld
  efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping
  efi: Fix handling of multiple efi_fake_mem= entries
  efi: Fix efi_memmap_alloc() leaks
  efi: Add tracking for dynamically allocated memmaps
  efi: Add a flags parameter to efi_memory_map
  efi: Fix comment for efi_mem_type() wrt absent physical addresses
  efi/arm: Defer probe of PCIe backed efifb on DT systems
  efi/x86: Limit EFI old memory map to SGI UV machines
  efi/x86: Avoid RWX mappings for all of DRAM
  efi/x86: Don't map the entire kernel text RW for mixed mode
  x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd
  efi/libstub/x86: Fix unused-variable warning
  efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode
  efi/libstub/x86: Use const attribute for efi_is_64bit()
  efi: Allow disabling PCI busmastering on bridges during boot
  efi/x86: Allow translating 64-bit arguments for mixed mode calls
  ...
2020-01-28 09:03:40 -08:00
Arnd Bergmann
34ca70ef7d sparc32: fix struct ipc64_perm type definition
As discussed in the strace issue tracker, it appears that the sparc32
sysvipc support has been broken for the past 11 years. It was however
working in compat mode, which is how it must have escaped most of the
regular testing.

The problem is that a cleanup patch inadvertently changed the uid/gid
fields in struct ipc64_perm from 32-bit types to 16-bit types in uapi
headers.

Both glibc and uclibc-ng still use the original types, so they should
work fine with compat mode, but not natively.  Change the definitions
to use __kernel_uid32_t and __kernel_gid32_t again.

Fixes: 83c86984bf ("sparc: unify ipcbuf.h")
Link: https://github.com/strace/strace/issues/116
Cc: <stable@vger.kernel.org> # v2.6.29
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: "Dmitry V . Levin" <ldv@altlinux.org>
Cc: Rich Felker <dalias@libc.org>
Cc: libc-alpha@sourceware.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-21 13:26:19 +01:00
Andreas Larsson
e2b9fc2dd6 sparc32, leon: Stop adding vendor and device id to prom ambapp path components
These extra fields before the @ are not handled in of_node_name_eq,
making commit b3e46d1a05 break node name
comparisons for ambapp path components, thereby making LEON systems
unable to boot.

As there is no need for the tacked on vendor and device ID fields in the
path component, resolve this situation by removing them.

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-21 13:24:35 +01:00
Aleksa Sarai
fddb5d430a open: introduce openat2(2) syscall
/* Background. */
For a very long time, extending openat(2) with new features has been
incredibly frustrating. This stems from the fact that openat(2) is
possibly the most famous counter-example to the mantra "don't silently
accept garbage from userspace" -- it doesn't check whether unknown flags
are present[1].

This means that (generally) the addition of new flags to openat(2) has
been fraught with backwards-compatibility issues (O_TMPFILE has to be
defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
kernels gave errors, since it's insecure to silently ignore the
flag[2]). All new security-related flags therefore have a tough road to
being added to openat(2).

Userspace also has a hard time figuring out whether a particular flag is
supported on a particular kernel. While it is now possible with
contemporary kernels (thanks to [3]), older kernels will expose unknown
flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during
openat(2) time matches modern syscall designs and is far more
fool-proof.

In addition, the newly-added path resolution restriction LOOKUP flags
(which we would like to expose to user-space) don't feel related to the
pre-existing O_* flag set -- they affect all components of path lookup.
We'd therefore like to add a new flag argument.

Adding a new syscall allows us to finally fix the flag-ignoring problem,
and we can make it extensible enough so that we will hopefully never
need an openat3(2).

/* Syscall Prototype. */
  /*
   * open_how is an extensible structure (similar in interface to
   * clone3(2) or sched_setattr(2)). The size parameter must be set to
   * sizeof(struct open_how), to allow for future extensions. All future
   * extensions will be appended to open_how, with their zero value
   * acting as a no-op default.
   */
  struct open_how { /* ... */ };

  int openat2(int dfd, const char *pathname,
              struct open_how *how, size_t size);

/* Description. */
The initial version of 'struct open_how' contains the following fields:

  flags
    Used to specify openat(2)-style flags. However, any unknown flag
    bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR)
    will result in -EINVAL. In addition, this field is 64-bits wide to
    allow for more O_ flags than currently permitted with openat(2).

  mode
    The file mode for O_CREAT or O_TMPFILE.

    Must be set to zero if flags does not contain O_CREAT or O_TMPFILE.

  resolve
    Restrict path resolution (in contrast to O_* flags they affect all
    path components). The current set of flags are as follows (at the
    moment, all of the RESOLVE_ flags are implemented as just passing
    the corresponding LOOKUP_ flag).

    RESOLVE_NO_XDEV       => LOOKUP_NO_XDEV
    RESOLVE_NO_SYMLINKS   => LOOKUP_NO_SYMLINKS
    RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS
    RESOLVE_BENEATH       => LOOKUP_BENEATH
    RESOLVE_IN_ROOT       => LOOKUP_IN_ROOT

open_how does not contain an embedded size field, because it is of
little benefit (userspace can figure out the kernel open_how size at
runtime fairly easily without it). It also only contains u64s (even
though ->mode arguably should be a u16) to avoid having padding fields
which are never used in the future.

Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE
is no longer permitted for openat(2). As far as I can tell, this has
always been a bug and appears to not be used by userspace (and I've not
seen any problems on my machines by disallowing it). If it turns out
this breaks something, we can special-case it and only permit it for
openat(2) but not openat2(2).

After input from Florian Weimer, the new open_how and flag definitions
are inside a separate header from uapi/linux/fcntl.h, to avoid problems
that glibc has with importing that header.

/* Testing. */
In a follow-up patch there are over 200 selftests which ensure that this
syscall has the correct semantics and will correctly handle several
attack scenarios.

In addition, I've written a userspace library[4] which provides
convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary
because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care
must be taken when using RESOLVE_IN_ROOT'd file descriptors with other
syscalls). During the development of this patch, I've run numerous
verification tests using libpathrs (showing that the API is reasonably
usable by userspace).

/* Future Work. */
Additional RESOLVE_ flags have been suggested during the review period.
These can be easily implemented separately (such as blocking auto-mount
during resolution).

Furthermore, there are some other proposed changes to the openat(2)
interface (the most obvious example is magic-link hardening[5]) which
would be a good opportunity to add a way for userspace to restrict how
O_PATH file descriptors can be re-opened.

Another possible avenue of future work would be some kind of
CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace
which openat2(2) flags and fields are supported by the current kernel
(to avoid userspace having to go through several guesses to figure it
out).

[1]: https://lwn.net/Articles/588444/
[2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com
[3]: commit 629e014bb8 ("fs: completely ignore unknown open flags")
[4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523
[5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/
[6]: https://youtu.be/ggD-eb3yPVs

Suggested-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-18 09:19:18 -05:00
Arvind Sankar
2f01bfc1ec arch/sparc/setup: Drop dummy_con initialization
con_init in tty/vt.c will now set conswitchp to dummy_con if it's unset.
Drop it from arch setup code.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20191218214506.49252-22-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 15:29:18 +01:00
Sargun Dhillon
9a2cef09c8
arch: wire up pidfd_getfd syscall
This wires up the pidfd_getfd syscall for all architectures.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200107175927.4558-4-sargun@sargun.me
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-01-13 21:49:47 +01:00
David S. Miller
548f0b9a5f sparc: Add .exit.data section.
This fixes build errors of all sorts.

Also, emit .exit.text unconditionally.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-12 00:07:42 -08:00
Ingo Molnar
57ad87ddce Merge branch 'x86/mm' into efi/core, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-10 18:53:14 +01:00