JIRA: https://issues.redhat.com/browse/RHEL-63880
Conflicts: Backport secretmem_mapping() from missing commit
f002882ca369 ("mm: merge folio_is_secretmem() and
folio_fast_pin_allowed() into gup_fast_folio_allowed()")
commit 5ac9b4e935dfc6af41eee2ddc21deb5c36507a9f
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Oct 17 10:47:13 2024 -0700
lib/buildid: Handle memfd_secret() files in build_id_parse()
>From memfd_secret(2) manpage:
The memory areas backing the file created with memfd_secret(2) are
visible only to the processes that have access to the file descriptor.
The memory region is removed from the kernel page tables and only the
page tables of the processes holding the file descriptor map the
corresponding physical memory. (Thus, the pages in the region can't be
accessed by the kernel itself, so that, for example, pointers to the
region can't be passed to system calls.)
We need to handle this special case gracefully in build ID fetching
code. Return -EFAULT whenever secretmem file is passed to build_id_parse()
family of APIs. Original report and repro can be found in [0].
[0] https://lore.kernel.org/bpf/ZwyG8Uro%2FSyTXAni@ly-workstation/
Fixes: de3ec364c3c3 ("lib/buildid: add single folio-based file reader abstraction")
Reported-by: Yi Lai <yi1.lai@intel.com>
Suggested-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://lore.kernel.org/bpf/20241017175431.6183-A-hca@linux.ibm.com
Link: https://lore.kernel.org/bpf/20241017174713.2157873-1-andrii@kernel.org
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit cdbb44f9a74fe7d01090ae492672e89cf7d83ce5
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:29 2024 -0700
lib/buildid: don't limit .note.gnu.build-id to the first page in ELF
With freader we don't need to restrict ourselves to a single page, so
let's allow ELF notes to be at any valid position with the file.
We also merge parse_build_id() and parse_build_id_buf() as now the only
difference between them is note offset overflow, which makes sense to
check in all situations.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit ad41251c290dfe3c01472c94d2439a59de23fe97
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:28 2024 -0700
lib/buildid: implement sleepable build_id_parse() API
Extend freader with a flag specifying whether it's OK to cause page
fault to fetch file data that is not already physically present in
memory. With this, it's now easy to wait for data if the caller is
running in sleepable (faultable) context.
We utilize read_cache_folio() to bring the desired folio into page
cache, after which the rest of the logic works just the same at folio level.
Suggested-by: Omar Sandoval <osandov@fb.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
Conflicts: Context change due to missing commit bdcb37a5d8de
("buildid: reduce header file dependencies for module")
commit 45b8fc3096542a53bfd245a9ad8ef870384b4897
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:27 2024 -0700
lib/buildid: rename build_id_parse() into build_id_parse_nofault()
Make it clear that build_id_parse() assumes that it can take no page
fault by renaming it and current few users to build_id_parse_nofault().
Also add build_id_parse() stub which for now falls back to non-sleepable
implementation, but will be changed in subsequent patches to take
advantage of sleepable context. PROCMAP_QUERY ioctl() on
/proc/<pid>/maps file is using build_id_parse() and will automatically
take advantage of more reliable sleepable context implementation.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit 4e9d360c4cdf2dc11a30fd5caf39e8c31f0896cb
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:26 2024 -0700
lib/buildid: remove single-page limit for PHDR search
Now that freader allows to access multiple pages transparently, there is
no need to limit program headers to the very first ELF file page. Remove
this limitation, but still put some sane limit on amount of program
headers that we are willing to iterate over (set arbitrarily to 256).
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit d4deb82423416e3ace7889816eea630af81fe702
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:25 2024 -0700
lib/buildid: take into account e_phoff when fetching program headers
Current code assumption is that program (segment) headers are following
ELF header immediately. This is a common case, but is not guaranteed. So
take into account e_phoff field of the ELF header when accessing program
headers.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit de3ec364c3c37971dbba1e37a55ae5b646c6f24e
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:24 2024 -0700
lib/buildid: add single folio-based file reader abstraction
Add freader abstraction that transparently manages fetching and local
mapping of the underlying file page(s) and provides a simple direct data
access interface.
freader_fetch() is the only and single interface necessary. It accepts
file offset and desired number of bytes that should be accessed, and
will return a kernel mapped pointer that caller can use to dereference
data up to requested size. Requested size can't be bigger than the size
of the extra buffer provided during initialization (because, worst case,
all requested data has to be copied into it, so it's better to flag
wrongly sized buffer unconditionally, regardless if requested data range
is crossing page boundaries or not).
If folio is not paged in, or some of the conditions are not satisfied,
NULL is returned and more detailed error code can be accessed through
freader->err field. This approach makes the usage of freader_fetch()
cleaner.
To accommodate accessing file data that crosses folio boundaries, user
has to provide an extra buffer that will be used to make a local copy,
if necessary. This is done to maintain a simple linear pointer data
access interface.
We switch existing build ID parsing logic to it, without changing or
lifting any of the existing constraints, yet. This will be done
separately.
Given existing code was written with the assumption that it's always
working with a single (first) page of the underlying ELF file, logic
passes direct pointers around, which doesn't really work well with
freader approach and would be limiting when removing the single page (folio)
limitation. So we adjust all the logic to work in terms of file offsets.
There is also a memory buffer-based version (freader_init_from_mem())
for cases when desired data is already available in kernel memory. This
is used for parsing vmlinux's own build ID note. In this mode assumption
is that provided data starts at "file offset" zero, which works great
when parsing ELF notes sections, as all the parsing logic is relative to
note section's start.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
Conflicts: Context change due to missing commit c44f063e740e
("buildid: use kmap_local_page()")
commit 905415ff3ffb1d7e5afa62bacabd79776bd24606
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 10:42:23 2024 -0700
lib/buildid: harden build ID parsing logic
Harden build ID parsing logic, adding explicit READ_ONCE() where it's
important to have a consistent value read and validated just once.
Also, as pointed out by Andi Kleen, we need to make sure that entire ELF
note is within a page bounds, so move the overflow check up and add an
extra note_size boundaries validation.
Fixes tag below points to the code that moved this code into
lib/buildid.c, and then subsequently was used in perf subsystem, making
this code exposed to perf_event_open() users in v5.12+.
Cc: stable@vger.kernel.org
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Jann Horn <jannh@google.com>
Suggested-by: Andi Kleen <ak@linux.intel.com>
Fixes: bd7525dacd ("bpf: Move stack_map_get_build_id into lib")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-63880
commit 961a2851324561caed579764ffbee3db82b32829
Author: Alexey Dobriyan <adobriyan@gmail.com>
Date: Fri Jun 21 21:39:33 2024 +0300
build-id: require program headers to be right after ELF header
Neither ELF spec not ELF loader require program header to be placed right
after ELF header, but build-id code very much assumes such placement:
See
find_get_page(vma->vm_file->f_mapping, 0);
line and checks against PAGE_SIZE.
Returns errors for now until someone rewrites build-id parser
to be more inline with load_elf_binary().
Link: https://lkml.kernel.org/r/d58bc281-6ca7-467a-9a64-40fa214bd63e@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
JIRA: https://issues.redhat.com/browse/RHEL-58641
Upstream Status: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Conflicts: There are conflicts in kernel/crash_core.c because dependency
commit 55c49fee57af ("mm/vmalloc: remove vmap_area_list") not
back ported yet; And commit d99e3140a4d3 ("mm: turn folio_test_hugetlb
into a PageType") which is later than this commit in upstream
has been merged into rhel.
commit 443cbaf9e2fdbef7d7cae457434a6cb8a679441b
Author: Baoquan He <bhe@redhat.com>
Date: Wed Jan 24 13:12:42 2024 +0800
crash: split vmcoreinfo exporting code out from crash_core.c
Now move the relevant codes into separate files:
kernel/crash_reserve.c, include/linux/crash_reserve.h.
And add config item CRASH_RESERVE to control its enabling.
And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
<linux/crash_core.h> and config item dependency on CRASH_CORE
accordingly.
And also do renaming as follows:
- arch/xxx/kernel/{crash_core.c => vmcore_info.c}
because they are only related to vmcoreinfo exporting on x86, arm64,
riscv.
And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
decide if build in crash_core.c.
[yang.lee@linux.alibaba.com: remove duplicated include in vmcore_info.c]
Link: https://lkml.kernel.org/r/20240126005744.16561-1-yang.lee@linux.alibaba.com
Link: https://lkml.kernel.org/r/20240124051254.67105-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pingfan Liu <piliu@redhat.com>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Michael Kelley <mhklinux@outlook.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2179848
commit 70e79866ab36feaaed8ef26dacfbcbac6a0631c9
Author: Alexey Dobriyan <adobriyan@gmail.com>
Date: Tue Feb 28 15:14:17 2023 +0300
ELF: fix all "Elf" typos
ELF is acronym and therefore should be spelled in all caps.
I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like
being written in the first person.
Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jaroslav Kysela <jkysela@redhat.com>
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>
These arguments are never modified so they can be marked const to indicate
as such.
Link: https://lkml.kernel.org/r/20210511003845.2429846-12-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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.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: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the running kernel's build ID[1] to the stacktrace information header.
This makes it simpler for developers to locate the vmlinux with full
debuginfo for a particular kernel stacktrace. Combined with
scripts/decode_stracktrace.sh, a developer can download the correct
vmlinux from a debuginfod[2] server and find the exact file and line
number for the functions plus offsets in a stacktrace.
This is especially useful for pstore crash debugging where the kernel
crashes are recorded in the pstore logs and the recovery kernel is
different or the debuginfo doesn't exist on the device due to space
concerns (the data can be large and a security concern). The stacktrace
can be analyzed after the crash by using the build ID to find the matching
vmlinux and understand where in the function something went wrong.
Example stacktrace from lkdtm:
WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm]
Modules linked in: lkdtm rfcomm algif_hash algif_skcipher af_alg xt_cgroup uinput xt_MASQUERADE
CPU: 4 PID: 3255 Comm: bash Not tainted 5.11 #3 aa23f7a1231c229de205662d5a9e0d4c580f19a1
Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
pstate: 00400009 (nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : lkdtm_WARNING+0x28/0x30 [lkdtm]
The hex string aa23f7a1231c229de205662d5a9e0d4c580f19a1 is the build ID,
following the kernel version number. Put it all behind a config option,
STACKTRACE_BUILD_ID, so that kernel developers can remove this
information if they decide it is too much.
Link: https://lkml.kernel.org/r/20210511003845.2429846-5-swboyd@chromium.org
Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1]
Link: https://sourceware.org/elfutils/Debuginfod.html [2]
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: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Parse the kernel's build ID at initialization so that other code can print
a hex format string representation of the running kernel's build ID. This
will be used in the kdump and dump_stack code so that developers can
easily locate the vmlinux debug symbols for a crash/stacktrace.
[swboyd@chromium.org: fix implicit declaration of init_vmlinux_build_id()]
Link: https://lkml.kernel.org/r/CAE-0n51UjTbay8N9FXAyE7_aR2+ePrQnKSRJ0gbmRsXtcLBVaw@mail.gmail.com
Link: https://lkml.kernel.org/r/20210511003845.2429846-4-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Baoquan He <bhe@redhat.com>
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: 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>
Add an API that can parse the build ID out of a buffer, instead of a vma,
to support printing a kernel module's build ID for stack traces.
Link: https://lkml.kernel.org/r/20210511003845.2429846-3-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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.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: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Add build ID to stacktraces", v6.
This series adds the kernel's build ID[1] to the stacktrace header printed
in oops messages, warnings, etc. and the build ID for any module that
appears in the stacktrace after the module name. The goal is to make the
stacktrace more self-contained and descriptive by including the relevant
build IDs in the kernel logs when something goes wrong. This can be used
by post processing tools like script/decode_stacktrace.sh and kernel
developers to easily locate the debug info associated with a kernel crash
and line up what line and file things started falling apart at.
To show how this can be used I've included a patch to decode_stacktrace.sh
that downloads the debuginfo from a debuginfod server. This also includes
some patches to make the buildid.c file use more const arguments and
consolidate logic into buildid.c from kdump. These are left to the end as
they were mostly cleanup patches.
Here's an example lkdtm stacktrace on arm64.
WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm]
Modules linked in: lkdtm rfcomm algif_hash algif_skcipher af_alg xt_cgroup uinput xt_MASQUERADE
CPU: 4 PID: 3255 Comm: bash Not tainted 5.11 #3 aa23f7a1231c229de205662d5a9e0d4c580f19a1
Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
pstate: 00400009 (nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : lkdtm_WARNING+0x28/0x30 [lkdtm]
lr : lkdtm_do_action+0x24/0x40 [lkdtm]
sp : ffffffc0134fbca0
x29: ffffffc0134fbca0 x28: ffffff92d53ba240
x27: 0000000000000000 x26: 0000000000000000
x25: 0000000000000000 x24: ffffffe3622352c0
x23: 0000000000000020 x22: ffffffe362233366
x21: ffffffe3622352e0 x20: ffffffc0134fbde0
x19: 0000000000000008 x18: 0000000000000000
x17: ffffff929b6536fc x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000012
x13: ffffffe380ed892c x12: ffffffe381d05068
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000001 x8 : ffffffe362237000
x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001
x3 : 0000000000000008 x2 : ffffff93fef25a70
x1 : ffffff93fef15788 x0 : ffffffe3622352e0
Call trace:
lkdtm_WARNING+0x28/0x30 [lkdtm ed5019fdf5e53be37cb1ba7899292d7e143b259e]
direct_entry+0x16c/0x1b4 [lkdtm ed5019fdf5e53be37cb1ba7899292d7e143b259e]
full_proxy_write+0x74/0xa4
vfs_write+0xec/0x2e8
ksys_write+0x84/0xf0
__arm64_sys_write+0x24/0x30
el0_svc_common+0xf4/0x1c0
do_el0_svc_compat+0x28/0x3c
el0_svc_compat+0x10/0x1c
el0_sync_compat_handler+0xa8/0xcc
el0_sync_compat+0x178/0x180
---[ end trace 3d95032303e59e68 ]---
This patch (of 13):
Some kernel elf files have various notes that also happen to have an elf
note type of '3', which matches NT_GNU_BUILD_ID but the note name isn't
"GNU". For example, this note trips up the existing logic:
Owner Data size Description
Xen 0x00000008 Unknown note type: (0x00000003) description data: 00 00 00 ffffff80 ffffffff ffffffff ffffffff ffffffff
Let's make sure that it is a GNU note when parsing the build ID so that we
can use this function to parse a vmlinux's build ID too.
Link: https://lkml.kernel.org/r/20210511003845.2429846-1-swboyd@chromium.org
Link: https://lkml.kernel.org/r/20210511003845.2429846-2-swboyd@chromium.org
Fixes: bd7525dacd ("bpf: Move stack_map_get_build_id into lib")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reported-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Matthew Wilcox <willy@infradead.org>
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: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's possible to have other build id types (other than default SHA1).
Currently there's also ld support for MD5 build id.
Adding size argument to build_id_parse function, that returns (if defined)
size of the parsed build id, so we can recognize the build id type.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-3-jolsa@kernel.org
Moving stack_map_get_build_id into lib with
declaration in linux/buildid.h header:
int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id);
This function returns build id for given struct vm_area_struct.
There is no functional change to stack_map_get_build_id function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-2-jolsa@kernel.org
Jerome Marchand
Baoquan He
Jaroslav Kysela
Stephen Boyd
Jiri Olsa