]> git.karo-electronics.de Git - linux-beck.git/commit
x86: Serialize EFI time accesses on rtc_lock
authorJan Beulich <JBeulich@novell.com>
Tue, 19 Jul 2011 10:53:07 +0000 (11:53 +0100)
committerIngo Molnar <mingo@elte.hu>
Thu, 21 Jul 2011 07:21:00 +0000 (09:21 +0200)
commitef68c8f87ed13f65df867dddf36c0e185b27b942
tree5caf15b1d46697bda2201fd1625d498e64df9f01
parentac619f4eba45da10053fc991f8a5d47b3be79fa3
x86: Serialize EFI time accesses on rtc_lock

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>
arch/x86/platform/efi/efi.c