[PATCH] use __pa_symbol to calculate the address of a C symbol.

[Glauber Costa]

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.

Signed-off-by: Glauber Costa <glommer@xxxxxxxxxx>
---
 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 223af43..e5efcdc 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);
-- 
1.6.2.2

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