On Thu, Feb 14, 2019 at 09:17:37AM +0100, Ard Biesheuvel wrote: > On Wed, 13 Feb 2019 at 20:34, Hedi Berriche <hedi.berriche@xxxxxxx> 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 > > > > Hi Hedi, > > The patches look good to me now. > > For the series, > > Reviewed-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > > However, I don't think all the patches should go to -stable. Only 4/4 > fixes an actual bug, and the remaining patches don't look like they > are prerequisites for that change. > > Also, if your colleagues reviewed your patches, now would be the time > to ask them to give their Reviewed-by as well. Reviewed-by: Russ Anderson <rja@xxxxxxx> Thanks. > -- > Ard. > > > > > --- > > > > 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 > > -- Russ Anderson, SuperDome Flex Linux Kernel Group Manager HPE - Hewlett Packard Enterprise (formerly SGI) rja@xxxxxxx
