diff options
| author | Glauber Costa <glommer@redhat.com> | 2009-08-31 03:04:31 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-09-24 08:44:06 -0700 |
| commit | 6aece86ef27f5713f7a34a3e4c844ad0ba29fbae (patch) | |
| tree | 96251d2cbd3d704ba31527b6f86dfddef4c956f1 | |
| parent | bd634611e589582bba636434af7fcbf782eceb42 (diff) | |
| download | lwn-6aece86ef27f5713f7a34a3e4c844ad0ba29fbae.tar.gz lwn-6aece86ef27f5713f7a34a3e4c844ad0ba29fbae.zip | |
KVM guest: fix bogus wallclock physical address calculation
commit a20316d2aa41a8f4fd171648bad8f044f6060826 upstream.
The use of __pa() to calculate the address of a C-visible symbol
is wrong, and can lead to unpredictable results. See arch/x86/include/asm/page.h
for details.
It should be replaced with __pa_symbol(), that does the correct math here,
by taking relocations into account. This ensures the correct wallclock data
structure physical address is passed to the hypervisor.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | arch/x86/kernel/kvmclock.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 223af43f1526..e5efcdcca31b 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -50,8 +50,8 @@ static unsigned long kvm_get_wallclock(void) struct timespec ts; int low, high; - low = (int)__pa(&wall_clock); - high = ((u64)__pa(&wall_clock) >> 32); + low = (int)__pa_symbol(&wall_clock); + high = ((u64)__pa_symbol(&wall_clock) >> 32); native_write_msr(MSR_KVM_WALL_CLOCK, low, high); vcpu_time = &get_cpu_var(hv_clock); |