diff options
| author | Baoquan He <bhe@redhat.com> | 2023-09-26 15:09:05 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-09-30 03:20:48 +0300 |
| commit | e2a8f20dd8e9df695f736e51cd9115ae55be92d1 (patch) | |
| tree | 035bcc68fdf06a1f68ba00281e5b228fdaadbf93 /mm | |
| parent | bbe246f875d064ecfb872fe4f66152e743dfd22d (diff) | |
| download | linux-e2a8f20dd8e9df695f736e51cd9115ae55be92d1.tar.xz | |
Crash: add lock to serialize crash hotplug handling
Eric reported that handling corresponding crash hotplug event can be
failed easily when many memory hotplug event are notified in a short
period. They failed because failing to take __kexec_lock.
=======
[ 78.714569] Fallback order for Node 0: 0
[ 78.714575] Built 1 zonelists, mobility grouping on. Total pages: 1817886
[ 78.717133] Policy zone: Normal
[ 78.724423] crash hp: kexec_trylock() failed, elfcorehdr may be inaccurate
[ 78.727207] crash hp: kexec_trylock() failed, elfcorehdr may be inaccurate
[ 80.056643] PEFILE: Unsigned PE binary
=======
The memory hotplug events are notified very quickly and very many, while
the handling of crash hotplug is much slower relatively. So the atomic
variable __kexec_lock and kexec_trylock() can't guarantee the
serialization of crash hotplug handling.
Here, add a new mutex lock __crash_hotplug_lock to serialize crash hotplug
handling specifically. This doesn't impact the usage of __kexec_lock.
Link: https://lkml.kernel.org/r/20230926120905.392903-1-bhe@redhat.com
Fixes: 247262756121 ("crash: add generic infrastructure for crash hotplug support")
Signed-off-by: Baoquan He <bhe@redhat.com>
Tested-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
0 files changed, 0 insertions, 0 deletions