For the series: Reviewed-by: Dimitri Sivanich <sivanich@xxxxxxx> On Wed, Feb 13, 2019 at 07:34:09PM +0000, Hedi Berriche wrote: > - Changes since v2 > Addressed comments from Ard Biesheuvel: > * expose efi_runtime_lock to UV platform only instead of globally > * remove unnecessary #ifdef CONFIG_EFI from bios_uv.c > > - Changes since v1: > Addressed comments from Bhupesh Sharma, Thomas Gleixner, and Ard Biesheuvel: > * made __uv_bios_call() static > * moved the efi_enabled() cleanup to its own patchlet > * explained the reason for renaming the efi_runtime_lock semaphore > * dropped the reviewed-bys as they should be given on the mailing list > * Cc'ng stable@xxxxxxxxxxxxxxx given the nature of the problem addressed by the patches > > --- > > Calls into UV BIOS were not being serialised which is wrong as it violates EFI > runtime rules, and bad as it does result in all sorts of potentially hard to > track down hangs and panics when efi_scratch.prev_mm gets clobbered whenever > efi_switch_mm() gets called concurrently from two different CPUs. > > Patch #1 removes an unnecessary #ifdef CONFIG_EFI guard from bios_uv.c. > > Patch #2 removes uv_bios_call_reentrant() because it's dead code. > > Patch #3 is a cleanup that drops test_bit() in favour of the ad hoc efi_enabled(). > > Patch #4 makes uv_bios_call() variants use the efi_runtime_lock semaphore to > protect against concurrency. > > Cc: Russ Anderson <rja@xxxxxxx> > Cc: Mike Travis <mike.travis@xxxxxxx> > Cc: Dimitri Sivanich <sivanich@xxxxxxx> > Cc: Steve Wahl <steve.wahl@xxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx # v4.9+ > > Hedi Berriche (4): > x86/platform/UV: remove unnecessary #ifdef CONFIG_EFI > x86/platform/UV: kill uv_bios_call_reentrant() as it has no callers > x86/platform/UV: use efi_enabled() instead of test_bit() > x86/platform/UV: use efi_runtime_lock to serialise BIOS calls > > arch/x86/include/asm/uv/bios.h | 13 ++++----- > arch/x86/platform/uv/bios_uv.c | 35 ++++++++++++++----------- > drivers/firmware/efi/runtime-wrappers.c | 7 +++++ > 3 files changed, 34 insertions(+), 21 deletions(-) > > -- > 2.20.1 >
