From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
commit 7cecb47f55e00282f972a1e0b09136c8cd938221 upstream.
extlog_init() uses rdmsrl() to read an MSR, which on older CPUs
provokes a error message at boot:
unchecked MSR access error: RDMSR from 0x179 at rIP: 0xcd047307 (native_read_msr+0x7/0x40)
Use rdmsrl_safe() instead, and return -ENODEV if it fails.
Reported-by: jim@xxxxxxxxxxx
Cc: All applicable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/acpi_extlog.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/acpi/acpi_extlog.c
+++ b/drivers/acpi/acpi_extlog.c
@@ -222,9 +222,9 @@ static int __init extlog_init(void)
u64 cap;
int rc;
- rdmsrl(MSR_IA32_MCG_CAP, cap);
-
- if (!(cap & MCG_ELOG_P) || !extlog_get_l1addr())
+ if (rdmsrl_safe(MSR_IA32_MCG_CAP, &cap) ||
+ !(cap & MCG_ELOG_P) ||
+ !extlog_get_l1addr())
return -ENODEV;
rc = -EINVAL;
