Commit Graph

32 Commits

Author SHA1 Message Date
Matthew Wilcox (Oracle) 1c5509be58 mm: remove 'First tail page' members from struct page
All former users now use the folio equivalents, so remove them from the
definition of struct page.

Link: https://lkml.kernel.org/r/20230111142915.1001531-23-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:59 -08:00
Stephen Brennan 08fc35f31b vmcoreinfo: warn if we exceed vmcoreinfo data size
Though vmcoreinfo is intended to be small, at just one page, useful
information is still added to it, so we risk running out of space. 
Currently there is no runtime check to see whether the vmcoreinfo buffer
has been exhausted.  Add a warning for this case.

Currently, my static checking tool[1] indicates that a good upper bound
for vmcoreinfo size is currently 3415 bytes, but the best time to add
warnings is before the risk becomes too high.

[1] https://github.com/brenns10/kernel_stuff/blob/master/vmcoreinfosize/vmcoreinfosize.py

Link: https://lkml.kernel.org/r/20221027205008.312534-1-stephen.s.brennan@oracle.com
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30 16:13:17 -08:00
Stephen Brennan f09bddbd86 vmcoreinfo: add kallsyms_num_syms symbol
The rest of the kallsyms symbols are useless without knowing the number of
symbols in the table.  In an earlier patch, I somehow dropped the
kallsyms_num_syms symbol, so add it back in.

Link: https://lkml.kernel.org/r/20220808205410.18590-1-stephen.s.brennan@oracle.com
Fixes: 5fd8fea935 ("vmcoreinfo: include kallsyms symbols")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Tao Liu 46d36b1be1 kdump: round up the total memory size to 128M for crashkernel reservation
The total memory size we get in kernel is usually slightly less than the
actual memory size because BIOS/firmware will reserve some memory region. 
So it won't export all memory as usable.

E.g, on my x86_64 kvm guest with 1G memory, the total_mem value shows:
UEFI boot with ovmf: 0x3faef000 Legacy boot kvm guest: 0x3ff7ec00

When specifying crashkernel=1G-2G:128M, if we have a 1G memory machine, we
get total size 1023M from firmware.  Then it will not fall into 1G-2G,
thus no memory reserved.  User will never know this, it is hard to let
user know the exact total value in kernel.

One way is to use dmi/smbios to get physical memory size, but it's not
reliable as well.  According to Prarit hardware vendors sometimes screw
this up.  Thus round up total size to 128M to work around this problem.

This patch is a resend of [1] and rebased onto v5.19-rc2, and the
original credit goes to Dave Young.

[1]: http://lists.infradead.org/pipermail/kexec/2018-April/020568.html

Link: https://lkml.kernel.org/r/20220627074440.187222-1-ltao@redhat.com
Signed-off-by: Tao Liu <ltao@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:31:40 -07:00
Stephen Brennan 5fd8fea935 vmcoreinfo: include kallsyms symbols
The internal kallsyms tables contain information which could be quite
useful to a debugging tool in the absence of other debuginfo.  If kallsyms
is enabled, then a debugging tool could parse it and use it as a fallback
symbol table.  Combined with BTF data, live & post-mortem debuggers can
support basic operations without needing a large DWARF debuginfo file
available.  As many as five symbols are necessary to properly parse
kallsyms names and addresses.  Add these to the vmcoreinfo note.

CONFIG_KALLSYMS_ABSOLUTE_PERCPU does impact the computation of symbol
addresses.  However, a debugger can infer this configuration value by
comparing the address of _stext in the vmcoreinfo with the address
computed via kallsyms.  So there's no need to include information about
this config value in the vmcoreinfo note.

To verify that we're still well below the maximum of 4096 bytes, I created
a script[1] to compute a rough upper bound on the possible size of
vmcoreinfo.  On v5.18-rc7, the script reports 3106 bytes, and with this
patch, the maximum become 3370 bytes.

[1]: https://github.com/brenns10/kernel_stuff/blob/master/vmcoreinfosize/

Link: https://lkml.kernel.org/r/20220517000508.777145-3-stephen.s.brennan@oracle.com
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Bixuan Cui <cuibixuan@huawei.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Vernet <void@manifault.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:31:39 -07:00
Linus Torvalds 6f664045c8 Not a lot of material this cycle. Many singleton patches against various
subsystems.   Most notably some maintenance work in ocfs2 and initramfs.
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Merge tag 'mm-nonmm-stable-2022-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc updates from Andrew Morton:
 "The non-MM patch queue for this merge window.

  Not a lot of material this cycle. Many singleton patches against
  various subsystems. Most notably some maintenance work in ocfs2
  and initramfs"

* tag 'mm-nonmm-stable-2022-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (65 commits)
  kcov: update pos before writing pc in trace function
  ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock
  ocfs2: dlmfs: don't clear USER_LOCK_ATTACHED when destroying lock
  fs/ntfs: remove redundant variable idx
  fat: remove time truncations in vfat_create/vfat_mkdir
  fat: report creation time in statx
  fat: ignore ctime updates, and keep ctime identical to mtime in memory
  fat: split fat_truncate_time() into separate functions
  MAINTAINERS: add Muchun as a memcg reviewer
  proc/sysctl: make protected_* world readable
  ia64: mca: drop redundant spinlock initialization
  tty: fix deadlock caused by calling printk() under tty_port->lock
  relay: remove redundant assignment to pointer buf
  fs/ntfs3: validate BOOT sectors_per_clusters
  lib/string_helpers: fix not adding strarray to device's resource list
  kernel/crash_core.c: remove redundant check of ck_cmdline
  ELF, uapi: fixup ELF_ST_TYPE definition
  ipc/mqueue: use get_tree_nodev() in mqueue_get_tree()
  ipc: update semtimedop() to use hrtimer
  ipc/sem: remove redundant assignments
  ...
2022-05-27 11:22:03 -07:00
lizhe a7bd57b87f kernel/crash_core.c: remove redundant check of ck_cmdline
At the end of get_last_crashkernel(), the judgement of ck_cmdline is
obviously unnecessary and causes redundance, let's clean it up.

Link: https://lkml.kernel.org/r/20220506104116.259323-1-sensor1010@163.com
Signed-off-by: lizhe <sensor1010@163.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Philipp Rudo <prudo@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-12 20:38:36 -07:00
Zhen Lei 2e5920bb07 kdump: return -ENOENT if required cmdline option does not exist
According to the current crashkernel=Y,low support in other ARCHes, it's
an optional command-line option. When it doesn't exist, kernel will try
to allocate minimum required memory below 4G automatically.

However, __parse_crashkernel() returns '-EINVAL' for all error cases. It
can't distinguish the nonexistent option from invalid option.

Change __parse_crashkernel() to return '-ENOENT' for the nonexistent option
case. With this change, crashkernel,low memory will take the default
value if crashkernel=,low is not specified; while crashkernel reservation
will fail and bail out if an invalid option is specified.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220506114402.365-2-thunder.leizhen@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-07 19:54:33 +01:00
Philipp Rudo 71d2bcec2d kernel/crash_core: suppress unknown crashkernel parameter warning
When booting with crashkernel= on the kernel command line a warning
similar to

    Kernel command line: ro console=ttyS0 crashkernel=256M
    Unknown kernel command line parameters "crashkernel=256M", will be passed to user space.

is printed.

This comes from crashkernel= being parsed independent from the kernel
parameter handling mechanism.  So the code in init/main.c doesn't know
that crashkernel= is a valid kernel parameter and prints this incorrect
warning.

Suppress the warning by adding a dummy early_param handler for
crashkernel=.

Link: https://lkml.kernel.org/r/20211208133443.6867-1-prudo@redhat.com
Fixes: 86d1919a4f ("init: print out unknown kernel parameters")
Signed-off-by: Philipp Rudo <prudo@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:55 -08:00
Stephen Boyd 44e8a5e912 kdump: use vmlinux_build_id to simplify
We can use the vmlinux_build_id array here now instead of open coding it.
This mostly consolidates code.

Link: https://lkml.kernel.org/r/20210511003845.2429846-14-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:22 -07:00
Mike Rapoport 43b02ba93b mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
After removal of the DISCONTIGMEM memory model the FLAT_NODE_MEM_MAP
configuration option is equivalent to FLATMEM.

Drop CONFIG_FLAT_NODE_MEM_MAP and use CONFIG_FLATMEM instead.

Link: https://lkml.kernel.org/r/20210608091316.3622-10-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:55 -07:00
Mike Rapoport a9ee6cf5c6 mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
After removal of DISCINTIGMEM the NEED_MULTIPLE_NODES and NUMA
configuration options are equivalent.

Drop CONFIG_NEED_MULTIPLE_NODES and use CONFIG_NUMA instead.

Done with

	$ sed -i 's/CONFIG_NEED_MULTIPLE_NODES/CONFIG_NUMA/' \
		$(git grep -wl CONFIG_NEED_MULTIPLE_NODES)
	$ sed -i 's/NEED_MULTIPLE_NODES/NUMA/' \
		$(git grep -wl NEED_MULTIPLE_NODES)

with manual tweaks afterwards.

[rppt@linux.ibm.com: fix arm boot crash]
  Link: https://lkml.kernel.org/r/YMj9vHhHOiCVN4BF@linux.ibm.com

Link: https://lkml.kernel.org/r/20210608091316.3622-9-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:55 -07:00
Pingfan Liu 4f5aecdff2 crash_core, vmcoreinfo: append 'SECTION_SIZE_BITS' to vmcoreinfo
As mentioned in kernel commit 1d50e5d0c5 ("crash_core, vmcoreinfo:
Append 'MAX_PHYSMEM_BITS' to vmcoreinfo"), SECTION_SIZE_BITS in the
formula:

    #define SECTIONS_SHIFT    (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)

Besides SECTIONS_SHIFT, SECTION_SIZE_BITS is also used to calculate
PAGES_PER_SECTION in makedumpfile just like kernel.

Unfortunately, this arch-dependent macro SECTION_SIZE_BITS changes, e.g.
recently in kernel commit f0b13ee232 ("arm64/sparsemem: reduce
SECTION_SIZE_BITS").  But user space wants a stable interface to get
this info.  Such info is impossible to be deduced from a crashdump
vmcore.  Hence append SECTION_SIZE_BITS to vmcoreinfo.

Link: https://lkml.kernel.org/r/20210608103359.84907-1-kernelfans@gmail.com
Link: http://lists.infradead.org/pipermail/kexec/2021-June/022676.html
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Bhupesh Sharma <bhupesh.sharma@linaro.org>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Boris Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-16 09:24:42 -07:00
Alexander Egorenkov ca4a9241cc kdump: append uts_namespace.name offset to VMCOREINFO
The offset of the field 'init_uts_ns.name' has changed since commit
9a56493f69 ("uts: Use generic ns_common::count").

Make the offset of the field 'uts_namespace.name' available in VMCOREINFO
because tools like 'crash-utility' and 'makedumpfile' must be able to read
it from crash dumps.

Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain
Link: https://lkml.kernel.org/r/20200930102328.396488-1-egorenar@linux.ibm.com
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: lijiang <lijiang@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 22:46:18 -08:00
Eric Biggers a24d22b225 crypto: sha - split sha.h into sha1.h and sha2.h
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2,
and <crypto/sha3.h> contains declarations for SHA-3.

This organization is inconsistent, but more importantly SHA-1 is no
longer considered to be cryptographically secure.  So to the extent
possible, SHA-1 shouldn't be grouped together with any of the other SHA
versions, and usage of it should be phased out.

Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and
<crypto/sha2.h>, and make everyone explicitly specify whether they want
the declarations for SHA-1, SHA-2, or both.

This avoids making the SHA-1 declarations visible to files that don't
want anything to do with SHA-1.  It also prepares for potentially moving
sha1.h into a new insecure/ or dangerous/ directory.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-11-20 14:45:33 +11:00
Vijay Balakrishna 0935288c6e kdump: append kernel build-id string to VMCOREINFO
Make kernel GNU build-id available in VMCOREINFO.  Having build-id in
VMCOREINFO facilitates presenting appropriate kernel namelist image with
debug information file to kernel crash dump analysis tools.  Currently
VMCOREINFO lacks uniquely identifiable key for crash analysis automation.

Regarding if this patch is necessary or matching of linux_banner and
OSRELEASE in VMCOREINFO employed by crash(8) meets the need -- IMO,
build-id approach more foolproof, in most instances it is a cryptographic
hash generated using internal code/ELF bits unlike kernel version string
upon which linux_banner is based that is external to the code.  I feel
each is intended for a different purpose.  Also OSRELEASE is not suitable
when two different kernel builds from same version with different features
enabled.

Currently for most linux (and non-linux) systems build-id can be extracted
using standard methods for file types such as user mode crash dumps,
shared libraries, loadable kernel modules etc., This is an exception for
linux kernel dump.  Having build-id in VMCOREINFO brings some uniformity
for automation tools.

Tyler said:

: I think this is a nice improvement over today's linux_banner approach for
: correlating vmlinux to a kernel dump.
:
: The elf notes parsing in this patch lines up with what is described in in
: the "Notes (Nhdr)" section of the elf(5) man page.
:
: BUILD_ID_MAX is sufficient to hold a sha1 build-id, which is the default
: build-id type today in GNU ld(2).  It is also sufficient to hold the
: "fast" build-id, which is the default build-id type today in LLVM lld(2).

Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1591849672-34104-1-git-send-email-vijayb@linux.microsoft.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:01 -07:00
Bhupesh Sharma 1d50e5d0c5 crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfo
Right now user-space tools like 'makedumpfile' and 'crash' need to rely
on a best-guess method of determining value of 'MAX_PHYSMEM_BITS'
supported by underlying kernel.

This value is used in user-space code to calculate the bit-space
required to store a section for SPARESMEM (similar to the existing
calculation method used in the kernel implementation):

  #define SECTIONS_SHIFT    (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)

Now, regressions have been reported in user-space utilities
like 'makedumpfile' and 'crash' on arm64, with the recently added
kernel support for 52-bit physical address space, as there is
no clear method of determining this value in user-space
(other than reading kernel CONFIG flags).

As per suggestion from makedumpfile maintainer (Kazu), it makes more
sense to append 'MAX_PHYSMEM_BITS' to vmcoreinfo in the core code itself
rather than in arch-specific code, so that the user-space code for other
archs can also benefit from this addition to the vmcoreinfo and use it
as a standard way of determining 'SECTIONS_SHIFT' value in user-land.

A reference 'makedumpfile' implementation which reads the
'MAX_PHYSMEM_BITS' value from vmcoreinfo in a arch-independent fashion
is available here:

While at it also update vmcoreinfo documentation for 'MAX_PHYSMEM_BITS'
variable being added to vmcoreinfo.

'MAX_PHYSMEM_BITS' defines the maximum supported physical address
space memory.

Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: John Donnelly <john.p.donnelly@oracle.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Boris Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: x86@kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: kexec@lists.infradead.org
Link: https://lore.kernel.org/r/1589395957-24628-2-git-send-email-bhsharma@redhat.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-02 17:56:11 +01:00
Thomas Gleixner 40b0b3f8fb treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
Based on 2 normalized pattern(s):

  this source code is licensed under the gnu general public license
  version 2 see the file copying for more details

  this source code is licensed under general public license version 2
  see

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 52 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:06 +02:00
David Hildenbrand e04b742f74 kexec: export PG_offline to VMCOREINFO
Right now, pages inflated as part of a balloon driver will be dumped by
dump tools like makedumpfile.  While XEN is able to check in the crash
kernel whether a certain pfn is actuall backed by memory in the
hypervisor (see xen_oldmem_pfn_is_ram) and optimize this case, dumps of
other balloon inflated memory will essentially result in zero pages
getting allocated by the hypervisor and the dump getting filled with
this data.

The allocation and reading of zero pages can directly be avoided if a
dumping tool could know which pages only contain stale information not
to be dumped.

We now have PG_offline which can be (and already is by virtio-balloon)
used for marking pages as logically offline.  Follow up patches will
make use of this flag also in other balloon implementations.

Let's export PG_offline via PAGE_OFFLINE_MAPCOUNT_VALUE, so makedumpfile
can directly skip pages that are logically offline and the content
therefore stale.

Please note that this is also helpful for a problem we were seeing under
Hyper-V: Dumping logically offline memory (pages kept fake offline while
onlining a section via online_page_callback) would under some condicions
result in a kernel panic when dumping them.

Link: http://lkml.kernel.org/r/20181119101616.8901-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:14 -08:00
Arnd Bergmann 91bc9aaf74 kernel/crash_core.c: print timestamp using time64_t
The get_seconds() call returns a 32-bit timestamp on some architectures,
and will overflow in the future.  The newer ktime_get_real_seconds()
always returns a 64-bit timestamp that does not suffer from this problem.

Link: http://lkml.kernel.org/r/20180618150329.941903-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Marc-Andr Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:47 -07:00
Omar Sandoval 23c85094fe proc/kcore: add vmcoreinfo note to /proc/kcore
The vmcoreinfo information is useful for runtime debugging tools, not just
for crash dumps.  A lot of this information can be determined by other
means, but this is much more convenient, and it only adds a page at most
to the file.

Link: http://lkml.kernel.org/r/fddbcd08eed76344863303878b12de1c1e2a04b6.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval <osandov@fb.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:46 -07:00
Omar Sandoval eff4345e7f crash_core: use VMCOREINFO_SYMBOL_ARRAY() for swapper_pg_dir
This is preparation for allowing CRASH_CORE to be enabled for any
architecture.

swapper_pg_dir is always either an array or a macro expanding to NULL.
In the latter case, VMCOREINFO_SYMBOL() won't work, as it tries to take
the address of the given symbol:

	#define VMCOREINFO_SYMBOL(name) \
		vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)

Instead, use VMCOREINFO_SYMBOL_ARRAY(), which uses the value:

	#define VMCOREINFO_SYMBOL_ARRAY(name) \
		vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)name)

This is the same thing for the array case but isn't an error for the macro
case.

Link: http://lkml.kernel.org/r/c05f9781ec204f40fc96f95086e7b6de6a3eb2c3.1532563124.git.osandov@fb.com
Signed-off-by: Omar Sandoval <osandov@fb.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:46 -07:00
Matthew Wilcox 6e292b9be7 mm: split page_type out from _mapcount
We're already using a union of many fields here, so stop abusing the
_mapcount and make page_type its own field.  That implies renaming some of
the machinery that creates PageBuddy, PageBalloon and PageKmemcg; bring
back the PG_buddy, PG_balloon and PG_kmemcg names.

As suggested by Kirill, make page_type a bitmask.  Because it starts out
life as -1 (thanks to sharing the storage with _mapcount), setting a page
flag means clearing the appropriate bit.  This gives us space for probably
twenty or so extra bits (depending how paranoid we want to be about
_mapcount underflow).

Link: http://lkml.kernel.org/r/20180518194519.3820-3-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:37 -07:00
Petr Tesarik 1cbf29da36 kexec: export PG_swapbacked to VMCOREINFO
Since commit 6326fec112 ("mm: Use owner_priv bit for PageSwapCache,
valid when PageSwapBacked"), PG_swapcache is an alias for
PG_owner_priv_1, which may be also used for other purposes.

To know whether the bit indeed has the PG_swapcache meaning, it is
necessary to check PG_swapbacked, hence this bit must be exported.

Link: http://lkml.kernel.org/r/20180410161345.142e142d@ezekiel.suse.cz
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "Marc-Andr Lureau" <marcandre.lureau@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
Marc-André Lureau 43d4cb47f6 crash: export paddr_vmcoreinfo_note()
The following patch is going to use the symbol from the fw_cfg module,
to call the function and write the note location details in the
vmcoreinfo entry, so qemu can produce dumps with the vmcoreinfo note.

CC: Andrew Morton <akpm@linux-foundation.org>
CC: Hari Bathini <hbathini@linux.vnet.ibm.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 03:17:41 +02:00
Kirill A. Shutemov a0b1280368 kdump: write correct address of mem_section into vmcoreinfo
Depending on configuration mem_section can now be an array or a pointer
to an array allocated dynamically.  In most cases, we can continue to
refer to it as 'mem_section' regardless of what it is.

But there's one exception: '&mem_section' means "address of the array"
if mem_section is an array, but if mem_section is a pointer, it would
mean "address of the pointer".

We've stepped onto this in kdump code.  VMCOREINFO_SYMBOL(mem_section)
writes down address of pointer into vmcoreinfo, not array as we wanted.

Let's introduce VMCOREINFO_SYMBOL_ARRAY() that would handle the
situation correctly for both cases.

Link: http://lkml.kernel.org/r/20180112162532.35896-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Fixes: 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-13 10:42:48 -08:00
Dave Young de40ccefd1 kdump: print a message in case parse_crashkernel_mem resulted in zero bytes
parse_crashkernel_mem() silently returns if we get zero bytes in the
parsing function.  It is useful for debugging to add a message,
especially if the kernel cannot boot correctly.

Add a pr_info instead of pr_warn because it is expected behavior for
size = 0, eg.  crashkernel=2G-4G:128M, size will be 0 in case system
memory is less than 2G.

Link: http://lkml.kernel.org/r/20171114080129.GA6115@dhcp-128-65.nay.redhat.com
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Xunlei Pang 1229384f5b kdump: protect vmcoreinfo data under the crash memory
Currently vmcoreinfo data is updated at boot time subsys_initcall(), it
has the risk of being modified by some wrong code during system is
running.

As a result, vmcore dumped may contain the wrong vmcoreinfo.  Later on,
when using "crash", "makedumpfile", etc utility to parse this vmcore, we
probably will get "Segmentation fault" or other unexpected errors.

E.g.  1) wrong code overwrites vmcoreinfo_data; 2) further crashes the
system; 3) trigger kdump, then we obviously will fail to recognize the
crash context correctly due to the corrupted vmcoreinfo.

Now except for vmcoreinfo, all the crash data is well
protected(including the cpu note which is fully updated in the crash
path, thus its correctness is guaranteed).  Given that vmcoreinfo data
is a large chunk prepared for kdump, we better protect it as well.

To solve this, we relocate and copy vmcoreinfo_data to the crash memory
when kdump is loading via kexec syscalls.  Because the whole crash
memory will be protected by existing arch_kexec_protect_crashkres()
mechanism, we naturally protect vmcoreinfo_data from write(even read)
access under kernel direct mapping after kdump is loaded.

Since kdump is usually loaded at the very early stage after boot, we can
trust the correctness of the vmcoreinfo data copied.

On the other hand, we still need to operate the vmcoreinfo safe copy
when crash happens to generate vmcoreinfo_note again, we rely on vmap()
to map out a new kernel virtual address and update to use this new one
instead in the following crash_save_vmcoreinfo().

BTW, we do not touch vmcoreinfo_note, because it will be fully updated
using the protected vmcoreinfo_data after crash which is surely correct
just like the cpu crash note.

Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:00 -07:00
Xunlei Pang 5203f4995d powerpc/fadump: use the correct VMCOREINFO_NOTE_SIZE for phdr
vmcoreinfo_max_size stands for the vmcoreinfo_data, the correct one we
should use is vmcoreinfo_note whose total size is VMCOREINFO_NOTE_SIZE.

Like explained in commit 77019967f0 ("kdump: fix exported size of
vmcoreinfo note"), it should not affect the actual function, but we
better fix it, also this change should be safe and backward compatible.

After this, we can get rid of variable vmcoreinfo_max_size, let's use
the corresponding macros directly, fewer variables means more safety for
vmcoreinfo operation.

[xlpang@redhat.com: fix build warning]
  Link: http://lkml.kernel.org/r/1494830606-27736-1-git-send-email-xlpang@redhat.com
Link: http://lkml.kernel.org/r/1493281021-20737-2-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:25:59 -07:00
Xunlei Pang 203e9e4121 kexec: move vmcoreinfo out of the kernel's .bss section
As Eric said,
 "what we need to do is move the variable vmcoreinfo_note out of the
  kernel's .bss section. And modify the code to regenerate and keep this
  information in something like the control page.

  Definitely something like this needs a page all to itself, and ideally
  far away from any other kernel data structures. I clearly was not
  watching closely the data someone decided to keep this silly thing in
  the kernel's .bss section."

This patch allocates extra pages for these vmcoreinfo_XXX variables, one
advantage is that it enhances some safety of vmcoreinfo, because
vmcoreinfo now is kept far away from other kernel data structures.

Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Suggested-by: Eric Biederman <ebiederm@xmission.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:25:59 -07:00
Hari Bathini 51dbd92520 ia64: reuse append_elf_note() and final_note() functions
Get rid of multiple definitions of append_elf_note() & final_note()
functions.  Reuse these functions compiled under CONFIG_CRASH_CORE Also,
define Elf_Word and use it instead of generic u32 or the more specific
Elf64_Word.

Link: http://lkml.kernel.org/r/149035342324.6881.11667840929850361402.stgit@hbathini.in.ibm.com
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.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>
2017-05-08 17:15:11 -07:00
Hari Bathini 692f66f26a crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE
Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and
reuse crashkernel parameter for fadump", v4.

Traditionally, kdump is used to save vmcore in case of a crash.  Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism.  Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.

This patchset removes dependency with CONFIG_KEXEC for crashkernel
parameter and vmcoreinfo related code as it can be reused without kexec
support.  Also, crashkernel parameter is reused instead of
fadump_reserve_mem to reserve memory for fadump.

The first patch moves crashkernel parameter parsing and vmcoreinfo
related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE.  The
second patch reuses the definitions of append_elf_note() & final_note()
functions under CONFIG_CRASH_CORE in IA64 arch code.  The third patch
removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump)
in powerpc.  The next patch reuses crashkernel parameter for reserving
memory for fadump, instead of the fadump_reserve_mem parameter.  This
has the advantage of using all syntaxes crashkernel parameter supports,
for fadump as well.  The last patch updates fadump kernel documentation
about use of crashkernel parameter.

This patch (of 5):

Traditionally, kdump is used to save vmcore in case of a crash.  Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism.  Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.

But currently, code related to vmcoreinfo and parsing of crashkernel
parameter is built under CONFIG_KEXEC_CORE.  This patch introduces
CONFIG_CRASH_CORE and moves the above mentioned code under this config,
allowing code reuse without dependency on CONFIG_KEXEC.  There is no
functional change with this patch.

Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.com
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.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>
2017-05-08 17:15:11 -07:00