x86: Serialize EFI time accesses on rtc_lock

Browse source

The EFI specification requires that callers of the time related
runtime functions serialize with other CMOS accesses in the
kernel, as the EFI time functions may choose to also use the
legacy CMOS RTC.

Besides fixing a latent bug, this is a prerequisite to safely
enable the rtc-efi driver for x86, which ought to be preferred
over rtc-cmos on all EFI platforms.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: <mjg@redhat.com>
Link: http://lkml.kernel.org/r/4E257E33020000780004E319@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Matthew Garrett <mjg@redhat.com>

...

This commit is contained in:

Jan Beulich 2011-07-19 11:53:07 +01:00 • committed by Ingo Molnar

parent ac619f4eba

commit ef68c8f87e

1 changed files with 33 additions and 6 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

39

arch/x86/platform/efi/efi.c

View file