1 files changed, 43 insertions, 32 deletions

diff --git a/arch/x86/lib/msr-smp.c b/arch/x86/lib/msr-smp.c
index ce68b6a9d7d1..b8f63419e6ae 100644
--- a/arch/x86/lib/msr-smp.c
+++ b/arch/x86/lib/msr-smp.c
@@ -1,16 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/export.h>
 #include <linux/preempt.h>
 #include <linux/smp.h>
+#include <linux/completion.h>
 #include <asm/msr.h>
 
 static void __rdmsr_on_cpu(void *info)
 {
 	struct msr_info *rv = info;
 	struct msr *reg;
-	int this_cpu = raw_smp_processor_id();
 
 	if (rv->msrs)
-		reg = per_cpu_ptr(rv->msrs, this_cpu);
+		reg = this_cpu_ptr(rv->msrs);
 	else
 		reg = &rv->reg;
 
@@ -21,10 +22,9 @@ static void __wrmsr_on_cpu(void *info)
 {
 	struct msr_info *rv = info;
 	struct msr *reg;
-	int this_cpu = raw_smp_processor_id();
 
 	if (rv->msrs)
-		reg = per_cpu_ptr(rv->msrs, this_cpu);
+		reg = this_cpu_ptr(rv->msrs);
 	else
 		reg = &rv->reg;
 
@@ -47,7 +47,7 @@ int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 }
 EXPORT_SYMBOL(rdmsr_on_cpu);
 
-int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+int rdmsrq_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
 {
 	int err;
 	struct msr_info rv;
@@ -60,7 +60,7 @@ int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
 
 	return err;
 }
-EXPORT_SYMBOL(rdmsrl_on_cpu);
+EXPORT_SYMBOL(rdmsrq_on_cpu);
 
 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 {
@@ -78,7 +78,7 @@ int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 }
 EXPORT_SYMBOL(wrmsr_on_cpu);
 
-int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+int wrmsrq_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
 {
 	int err;
 	struct msr_info rv;
@@ -92,10 +92,10 @@ int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
 
 	return err;
 }
-EXPORT_SYMBOL(wrmsrl_on_cpu);
+EXPORT_SYMBOL(wrmsrq_on_cpu);
 
 static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
-			    struct msr *msrs,
+			    struct msr __percpu *msrs,
 			    void (*msr_func) (void *info))
 {
 	struct msr_info rv;
@@ -122,7 +122,7 @@ static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
  * @msrs:       array of MSR values
  *
  */
-void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs)
+void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
 {
 	__rwmsr_on_cpus(mask, msr_no, msrs, __rdmsr_on_cpu);
 }
@@ -136,19 +136,25 @@ EXPORT_SYMBOL(rdmsr_on_cpus);
  * @msrs:       array of MSR values
  *
  */
-void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs)
+void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
 {
 	__rwmsr_on_cpus(mask, msr_no, msrs, __wrmsr_on_cpu);
 }
 EXPORT_SYMBOL(wrmsr_on_cpus);
 
+struct msr_info_completion {
+	struct msr_info		msr;
+	struct completion	done;
+};
+
 /* These "safe" variants are slower and should be used when the target MSR
    may not actually exist. */
 static void __rdmsr_safe_on_cpu(void *info)
 {
-	struct msr_info *rv = info;
+	struct msr_info_completion *rv = info;
 
-	rv->err = rdmsr_safe(rv->msr_no, &rv->reg.l, &rv->reg.h);
+	rv->msr.err = rdmsr_safe(rv->msr.msr_no, &rv->msr.reg.l, &rv->msr.reg.h);
+	complete(&rv->done);
 }
 
 static void __wrmsr_safe_on_cpu(void *info)
@@ -160,17 +166,25 @@ static void __wrmsr_safe_on_cpu(void *info)
 
 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 {
+	struct msr_info_completion rv;
+	call_single_data_t csd;
 	int err;
-	struct msr_info rv;
+
+	INIT_CSD(&csd, __rdmsr_safe_on_cpu, &rv);
 
 	memset(&rv, 0, sizeof(rv));
+	init_completion(&rv.done);
+	rv.msr.msr_no = msr_no;
 
-	rv.msr_no = msr_no;
-	err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
-	*l = rv.reg.l;
-	*h = rv.reg.h;
+	err = smp_call_function_single_async(cpu, &csd);
+	if (!err) {
+		wait_for_completion(&rv.done);
+		err = rv.msr.err;
+	}
+	*l = rv.msr.reg.l;
+	*h = rv.msr.reg.h;
 
-	return err ? err : rv.err;
+	return err;
 }
 EXPORT_SYMBOL(rdmsr_safe_on_cpu);
 
@@ -190,7 +204,7 @@ int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 }
 EXPORT_SYMBOL(wrmsr_safe_on_cpu);
 
-int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+int wrmsrq_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
 {
 	int err;
 	struct msr_info rv;
@@ -204,22 +218,19 @@ int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
 
 	return err ? err : rv.err;
 }
-EXPORT_SYMBOL(wrmsrl_safe_on_cpu);
+EXPORT_SYMBOL(wrmsrq_safe_on_cpu);
 
-int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+int rdmsrq_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));
 
-	rv.msr_no = msr_no;
-	err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
-	*q = rv.reg.q;
+	err = rdmsr_safe_on_cpu(cpu, msr_no, &low, &high);
+	*q = (u64)high << 32 | low;
 
-	return err ? err : rv.err;
+	return err;
 }
-EXPORT_SYMBOL(rdmsrl_safe_on_cpu);
+EXPORT_SYMBOL(rdmsrq_safe_on_cpu);
 
 /*
  * These variants are significantly slower, but allows control over
@@ -239,7 +250,7 @@ static void __wrmsr_safe_regs_on_cpu(void *info)
 	rv->err = wrmsr_safe_regs(rv->regs);
 }
 
-int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
+int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
 {
 	int err;
 	struct msr_regs_info rv;
@@ -252,7 +263,7 @@ int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
 }
 EXPORT_SYMBOL(rdmsr_safe_regs_on_cpu);
 
-int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
+int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
 {
 	int err;
 	struct msr_regs_info rv;