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| author | Hoeun Ryu <hoeun.ryu@gmail.com> | 2017-08-17 04:24:27 +0200 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2017-08-21 19:01:04 +0200 |
| commit | a88ce63b642cf8cd82cbc278429ccd9de4455a07 (patch) | |
| tree | dca6db72c66d83af27733dcbca50f5d89f55e1a8 /arch/arm64/include/asm/smp.h | |
| parent | arm64: dma-mapping: Mark atomic_pool as __ro_after_init (diff) | |
| download | linux-a88ce63b642cf8cd82cbc278429ccd9de4455a07.tar.xz linux-a88ce63b642cf8cd82cbc278429ccd9de4455a07.zip | |
arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic cores
Commit 0ee5941 : (x86/panic: replace smp_send_stop() with kdump friendly
version in panic path) introduced crash_smp_send_stop() which is a weak
function and can be overridden by architecture codes to fix the side effect
caused by commit f06e515 : (kernel/panic.c: add "crash_kexec_post_
notifiers" option).
ARM64 architecture uses the weak version function and the problem is that
the weak function simply calls smp_send_stop() which makes other CPUs
offline and takes away the chance to save crash information for nonpanic
CPUs in machine_crash_shutdown() when crash_kexec_post_notifiers kernel
option is enabled.
Calling smp_send_crash_stop() in machine_crash_shutdown() is useless
because all nonpanic CPUs are already offline by smp_send_stop() in this
case and smp_send_crash_stop() only works against online CPUs.
The result is that secondary CPUs registers are not saved by
crash_save_cpu() and the vmcore file misreports these CPUs as being
offline.
crash_smp_send_stop() is implemented to fix this problem by replacing the
existing smp_send_crash_stop() and adding a check for multiple calling to
the function. The function (strong symbol version) saves crash information
for nonpanic CPUs and machine_crash_shutdown() tries to save crash
information for nonpanic CPUs only when crash_kexec_post_notifiers kernel
option is disabled.
* crash_kexec_post_notifiers : false
panic()
__crash_kexec()
machine_crash_shutdown()
crash_smp_send_stop() <= save crash dump for nonpanic cores
* crash_kexec_post_notifiers : true
panic()
crash_smp_send_stop() <= save crash dump for nonpanic cores
__crash_kexec()
machine_crash_shutdown()
crash_smp_send_stop() <= just return.
Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/smp.h')
| -rw-r--r-- | arch/arm64/include/asm/smp.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index 55f08c5acfad..f82b447bd34f 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -148,7 +148,7 @@ static inline void cpu_panic_kernel(void) */ bool cpus_are_stuck_in_kernel(void); -extern void smp_send_crash_stop(void); +extern void crash_smp_send_stop(void); extern bool smp_crash_stop_failed(void); #endif /* ifndef __ASSEMBLY__ */ |