diff options
| author | Jiaqing Zhao <jiaqing.zhao@linux.intel.com> | 2025-05-09 17:06:33 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-06-19 15:31:32 +0200 |
| commit | d3cc08bad4b7fcb7eba82a0705a3fa74fb244823 (patch) | |
| tree | e26841b9c321cef21b8580a25ba28262fe626c76 | |
| parent | f551f0e630a766e0a73167ffc57be0ef3a090a47 (diff) | |
x86/mtrr: Check if fixed-range MTRRs exist in mtrr_save_fixed_ranges()
[ Upstream commit 824c6384e8d9275d4ec7204f3f79a4ac6bc10379 ]
When suspending, save_processor_state() calls mtrr_save_fixed_ranges()
to save fixed-range MTRRs.
On platforms without fixed-range MTRRs like the ACRN hypervisor which
has removed fixed-range MTRR emulation, accessing these MSRs will
trigger an unchecked MSR access error. Make sure fixed-range MTRRs are
supported before access to prevent such error.
Since mtrr_state.have_fixed is only set when MTRRs are present and
enabled, checking the CPU feature flag in mtrr_save_fixed_ranges() is
unnecessary.
Fixes: 3ebad5905609 ("[PATCH] x86: Save and restore the fixed-range MTRRs of the BSP when suspending")
Signed-off-by: Jiaqing Zhao <jiaqing.zhao@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250509170633.3411169-2-jiaqing.zhao@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/generic.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c index 7b29ebda024f..1ececfce7a46 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -591,7 +591,7 @@ static void get_fixed_ranges(mtrr_type *frs) void mtrr_save_fixed_ranges(void *info) { - if (boot_cpu_has(X86_FEATURE_MTRR)) + if (mtrr_state.have_fixed) get_fixed_ranges(mtrr_state.fixed_ranges); } |