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| author | Baoquan He <bhe@redhat.com> | 2021-01-22 15:42:14 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-02-03 23:23:23 +0100 |
| commit | 8445d9564504e40fd0e3b5323079d4ea02715030 (patch) | |
| tree | a36abdd5c4e39bbfc0cc74551a26f94601c9e144 | |
| parent | 98fa0addc3ce9d6ad079059c46a1ae53fa3c92d6 (diff) | |
| download | linux-stable-8445d9564504e40fd0e3b5323079d4ea02715030.tar.gz linux-stable-8445d9564504e40fd0e3b5323079d4ea02715030.tar.bz2 linux-stable-8445d9564504e40fd0e3b5323079d4ea02715030.zip | |
kernel: kexec: remove the lock operation of system_transition_mutex
commit 56c91a18432b631ca18438841fd1831ef756cabf upstream.
Function kernel_kexec() is called with lock system_transition_mutex
held in reboot system call. While inside kernel_kexec(), it will
acquire system_transition_mutex agin. This will lead to dead lock.
The dead lock should be easily triggered, it hasn't caused any
failure report just because the feature 'kexec jump' is almost not
used by anyone as far as I know. An inquiry can be made about who
is using 'kexec jump' and where it's used. Before that, let's simply
remove the lock operation inside CONFIG_KEXEC_JUMP ifdeffery scope.
Fixes: 55f2503c3b69 ("PM / reboot: Eliminate race between reboot and suspend")
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Pingfan Liu <kernelfans@gmail.com>
Cc: 4.19+ <stable@vger.kernel.org> # 4.19+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/kexec_core.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index faeec8255e7e..6b3d7f7211dd 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -1130,7 +1130,6 @@ int kernel_kexec(void) #ifdef CONFIG_KEXEC_JUMP if (kexec_image->preserve_context) { - lock_system_sleep(); pm_prepare_console(); error = freeze_processes(); if (error) { @@ -1193,7 +1192,6 @@ int kernel_kexec(void) thaw_processes(); Restore_console: pm_restore_console(); - unlock_system_sleep(); } #endif |