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_n

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 <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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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_RESERV

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.

[[email protected]: remove duplicated include in vmcore_info.c]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Baoquan He <[email protected]>
Signed-off-by: Yang Li <[email protected]>
Acked-by: Hari Bathini <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Pingfan Liu <[email protected]>
Cc: Klara Modin <[email protected]>
Cc: Michael Kelley <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Yang Li <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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buildid: reduce header file dependencies for module

The vmlinux decompressor code intentionally has only a limited set of
included header files, but this started running into a build failure
because

buildid: reduce header file dependencies for module

The vmlinux decompressor code intentionally has only a limited set of
included header files, but this started running into a build failure
because of the bitmap logic needing linux/errno.h:

In file included from include/linux/cpumask.h:12,
from include/linux/mm_types_task.h:14,
from include/linux/mm_types.h:5,
from include/linux/buildid.h:5,
from include/linux/module.h:14,
from arch/arm/boot/compressed/../../../../lib/lz4/lz4_decompress.c:39,
from arch/arm/boot/compressed/../../../../lib/decompress_unlz4.c:10,
from arch/arm/boot/compressed/decompress.c:60:
include/linux/bitmap.h: In function 'bitmap_allocate_region':
include/linux/bitmap.h:527:25: error: 'EBUSY' undeclared (first use in this function)
527 | return -EBUSY;
| ^~~~~
include/linux/bitmap.h:527:25: note: each undeclared identifier is reported only once for each function it appears in
include/linux/bitmap.h: In function 'bitmap_find_free_region':
include/linux/bitmap.h:554:17: error: 'ENOMEM' undeclared (first use in this function)
554 | return -ENOMEM;
| ^~~~~~

This is easily avoided by changing linux/buildid.h to no longer depend on
linux/mm_types.h, a header that pulls in a huge number of indirect dependencies.

Fixes: b9c957f554442 ("bitmap: move bitmap_*_region() functions to bitmap.h")
Fixes: bd7525dacd7e2 ("bpf: Move stack_map_get_build_id into lib")
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Yury Norov <[email protected]>

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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/20210511003845.24298

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/[email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Evan Green <[email protected]>
Cc: Hsin-Yi Wang <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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dump_stack: add vmlinux build ID to stack traces

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
debug

dump_stack: add vmlinux build ID to stack traces

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/[email protected]
Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1]
Link: https://sourceware.org/elfutils/Debuginfod.html [2]
Signed-off-by: Stephen Boyd <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Evan Green <[email protected]>
Cc: Hsin-Yi Wang <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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buildid: stash away kernels build ID on init

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
wil

buildid: stash away kernels build ID on init

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.

[[email protected]: 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/[email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Evan Green <[email protected]>
Cc: Hsin-Yi Wang <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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buildid: add API to parse build ID out of buffer

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: htt

buildid: add API to parse build ID out of buffer

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/[email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Evan Green <[email protected]>
Cc: Hsin-Yi Wang <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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bpf: Add size arg to build_id_parse function

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_

bpf: Add size arg to build_id_parse function

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 <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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bpf: Move stack_map_get_build_id into lib

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

bpf: Move stack_map_get_build_id into lib

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 <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Song Liu <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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