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| author | Ben Hutchings <ben@decadent.org.uk> | 2020-09-27 23:50:42 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2020-10-02 19:01:55 +0200 |
| commit | 7cecb47f55e00282f972a1e0b09136c8cd938221 (patch) | |
| tree | bf016b79779583ffdc402c6c94924728e372046c /drivers/acpi/acpi_extlog.c | |
| parent | Linux 5.9-rc7 (diff) | |
| download | linux-7cecb47f55e00282f972a1e0b09136c8cd938221.tar.xz linux-7cecb47f55e00282f972a1e0b09136c8cd938221.zip | |
ACPI / extlog: Check for RDMSR failure
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@photojim.ca
References: https://bugs.debian.org/971058
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/acpi_extlog.c')
| -rw-r--r-- | drivers/acpi/acpi_extlog.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c index f138e12b7b82..72f1fb77abcd 100644 --- 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; |