x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT

For some reason, the _safe MSR functions returned -EFAULT, not -EIO.
However, the only user which cares about the return code as anything
other than a boolean is the MSR driver, which wants -EIO.  Change it
to -EIO across the board.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 09c5ca70d49dea8f3a7e9de7042006e5ee5d6603..943fdd572e16938682cbe83ef345745e838918a0 100644 (file)
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -67,7 +67,7 @@ static inline unsigned long long native_read_msr_safe(unsigned int msr,
                     ".previous\n\t"
                     _ASM_EXTABLE(2b, 3b)
                     : [err] "=r" (*err), EAX_EDX_RET(val, low, high)
-                    : "c" (msr), [fault] "i" (-EFAULT));
+                    : "c" (msr), [fault] "i" (-EIO));
        return EAX_EDX_VAL(val, low, high);
 }
 
@@ -90,7 +90,7 @@ notrace static inline int native_write_msr_safe(unsigned int msr,
                     _ASM_EXTABLE(2b, 3b)
                     : [err] "=a" (err)
                     : "c" (msr), "0" (low), "d" (high),
-                      [fault] "i" (-EFAULT)
+                      [fault] "i" (-EIO)
                     : "memory");
        return err;
 }

diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
index 98fd6cd4e3a479e8e1cea7a4ccfad7063f921850..2cfbb4b2c422e971c9c528c5ec505385fb89c0ca 100644 (file)
--- a/arch/x86/kernel/msr.c
+++ b/arch/x86/kernel/msr.c
@@ -80,11 +80,8 @@ static ssize_t msr_read(struct file *file, char __user *buf,
 
        for (; count; count -= 8) {
                err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]);
-               if (err) {
-                       if (err == -EFAULT) /* Fix idiotic error code */
-                               err = -EIO;
+               if (err)
                        break;
-               }
                if (copy_to_user(tmp, &data, 8)) {
                        err = -EFAULT;
                        break;
@@ -115,11 +112,8 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
                        break;
                }
                err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]);
-               if (err) {
-                       if (err == -EFAULT) /* Fix idiotic error code */
-                               err = -EIO;
+               if (err)
                        break;
-               }
                tmp += 2;
                bytes += 8;
        }

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 0a1700a2be9c8c9a548822ca4deef1bb475b4059..a8432d816903a8fe4b8d2d9b071b80f35de06366 100644 (file)
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -713,7 +713,7 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
        set:
                base = ((u64)high << 32) | low;
                if (HYPERVISOR_set_segment_base(which, base) != 0)
-                       ret = -EFAULT;
+                       ret = -EIO;
                break;
 #endif