mirror of
https://github.com/torvalds/linux.git
synced 2024-11-08 13:11:45 +00:00
e59310adf5
[Issue] There is a scenario which efi_pstore may hang up: - cpuA grabs efivars->lock - cpuB panics and calls smp_send_stop - smp_send_stop sends IRQ to cpuA - after 1 second, cpuB gives up on cpuA and sends an NMI instead - cpuA is now in an NMI handler while still holding efivars->lock - cpuB is deadlocked This case may happen if a firmware has a bug and cpuA is stuck talking with it. [Solution] This patch changes a spin_lock to a spin_trylock in non-blocking paths. and if the spin_lock has already taken by another cpu, it returns without accessing to a firmware to avoid the deadlock. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Acked-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Tony Luck <tony.luck@intel.com> |
||
|---|---|---|
| .. | ||
| dcdbas.c | ||
| dcdbas.h | ||
| dell_rbu.c | ||
| dmi_scan.c | ||
| dmi-id.c | ||
| dmi-sysfs.c | ||
| edd.c | ||
| efivars.c | ||
| iscsi_ibft_find.c | ||
| iscsi_ibft.c | ||
| Kconfig | ||
| Makefile | ||
| memmap.c | ||
| pcdp.c | ||
| pcdp.h | ||