From 8d75f7b4a3dfd5714a5dc87cfdaa27bd2d14aa48 Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Wed, 27 Apr 2022 03:03:04 -0700 Subject: [PATCH] platform/x86: intel-uncore-freq: Prevent driver loading in guests Loading this driver in guests results in unchecked MSR access error for MSR 0x620. There is no use of reading and modifying package/die scope uncore MSRs in guests. So check for CPU feature X86_FEATURE_HYPERVISOR to prevent loading of this driver in guests. Fixes: dbce412a7733 ("platform/x86/intel-uncore-freq: Split common and enumeration part") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215870 Suggested-by: Borislav Petkov Signed-off-by: Srinivas Pandruvada Link: https://lore.kernel.org/r/20220427100304.2562990-1-srinivas.pandruvada@linux.intel.com Signed-off-by: Hans de Goede --- drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c index c61f804..8f9c571 100644 --- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c @@ -212,6 +212,9 @@ static int __init intel_uncore_init(void) const struct x86_cpu_id *id; int ret; + if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR)) + return -ENODEV; + id = x86_match_cpu(intel_uncore_cpu_ids); if (!id) return -ENODEV; -- 2.7.4