[PATCH] x86, msr: fix rdmsrl_safe_on_cpu()

From: Eric Dumazet
Date: Tue Mar 27 2018 - 23:22:52 EST


When changing rdmsr_safe_on_cpu() to schedule, I missed that
__rdmsr_safe_on_cpu() was also used by rdmsrl_safe_on_cpu()

Lets make rdmsrl_safe_on_cpu() a wrapper instead of copy/pasting
the code I added for the completion handling.

Fixes: 07cde313b2d2 ("x86/msr: Allow rdmsr_safe_on_cpu() to schedule")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
---
arch/x86/lib/msr-smp.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/arch/x86/lib/msr-smp.c b/arch/x86/lib/msr-smp.c
index 761ba062afdaf7f7d0603ed94ed6cc3e46b37f76..fee8b9c0520c9954e3cf9093332e1a9b53009b8b 100644
--- a/arch/x86/lib/msr-smp.c
+++ b/arch/x86/lib/msr-smp.c
@@ -225,16 +225,13 @@ EXPORT_SYMBOL(wrmsrl_safe_on_cpu);

int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
{
+ u32 low, high;
int err;
- struct msr_info rv;

- memset(&rv, 0, sizeof(rv));
+ err = rdmsr_safe_on_cpu(cpu, msr_no, &low, &high);
+ *q = (u64)high << 32 | low;

- rv.msr_no = msr_no;
- err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
- *q = rv.reg.q;
-
- return err ? err : rv.err;
+ return err;
}
EXPORT_SYMBOL(rdmsrl_safe_on_cpu);

--
2.17.0.rc1.321.gba9d0f2565-goog