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-rw-r--r--arch/x86/kernel/cpu/amd.c17
-rw-r--r--arch/x86/kernel/cpu/mshyperv.c11
-rw-r--r--arch/x86/kernel/cpu/scattered.c1
3 files changed, 28 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index a6f88ca1a6b4..5398db4dedb4 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -546,6 +546,23 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
u64 msr;
/*
+ * Mark using WBINVD is needed during kexec on processors that
+ * support SME. This provides support for performing a successful
+ * kexec when going from SME inactive to SME active (or vice-versa).
+ *
+ * The cache must be cleared so that if there are entries with the
+ * same physical address, both with and without the encryption bit,
+ * they don't race each other when flushed and potentially end up
+ * with the wrong entry being committed to memory.
+ *
+ * Test the CPUID bit directly because with mem_encrypt=off the
+ * BSP will clear the X86_FEATURE_SME bit and the APs will not
+ * see it set after that.
+ */
+ if (c->extended_cpuid_level >= 0x8000001f && (cpuid_eax(0x8000001f) & BIT(0)))
+ __this_cpu_write(cache_state_incoherent, true);
+
+ /*
* BIOS support is required for SME and SEV.
* For SME: If BIOS has enabled SME then adjust x86_phys_bits by
* the SME physical address space reduction value.
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index c78f860419d6..25773af116bc 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -565,6 +565,11 @@ static void __init ms_hyperv_init_platform(void)
machine_ops.crash_shutdown = hv_machine_crash_shutdown;
#endif
#endif
+ /*
+ * HV_ACCESS_TSC_INVARIANT is always zero for the root partition. Root
+ * partition doesn't need to write to synthetic MSR to enable invariant
+ * TSC feature. It sees what the hardware provides.
+ */
if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
/*
* Writing to synthetic MSR 0x40000118 updates/changes the
@@ -636,8 +641,12 @@ static void __init ms_hyperv_init_platform(void)
* TSC should be marked as unstable only after Hyper-V
* clocksource has been initialized. This ensures that the
* stability of the sched_clock is not altered.
+ *
+ * HV_ACCESS_TSC_INVARIANT is always zero for the root partition. No
+ * need to check for it.
*/
- if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT))
+ if (!hv_root_partition() &&
+ !(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT))
mark_tsc_unstable("running on Hyper-V");
hardlockup_detector_disable();
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 4cee6213d667..caa4dc885c21 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -27,6 +27,7 @@ static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
{ X86_FEATURE_INTEL_PPIN, CPUID_EBX, 0, 0x00000007, 1 },
+ { X86_FEATURE_MSR_IMM, CPUID_ECX, 5, 0x00000007, 1 },
{ X86_FEATURE_APX, CPUID_EDX, 21, 0x00000007, 1 },
{ X86_FEATURE_RRSBA_CTRL, CPUID_EDX, 2, 0x00000007, 2 },
{ X86_FEATURE_BHI_CTRL, CPUID_EDX, 4, 0x00000007, 2 },