diff options
| author | Kirill A. Shutemov <[email protected]> | 2024-10-15 12:58:17 +0300 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2024-10-20 07:07:02 -0400 |
| commit | 8e690b817e38769dc2fa0e7473e5a5dc1fc25795 (patch) | |
| tree | bbe51d126b176306c2f51dba5520354cea20a058 | |
| parent | bc07eea2f3b330127242df2e0ec2d6cd16b4f2e8 (diff) | |
x86/kvm: Override default caching mode for SEV-SNP and TDX
AMD SEV-SNP and Intel TDX have limited access to MTRR: either it is not
advertised in CPUID or it cannot be programmed (on TDX, due to #VE on
CR0.CD clear).
This results in guests using uncached mappings where it shouldn't and
pmd/pud_set_huge() failures due to non-uniform memory type reported by
mtrr_type_lookup().
Override MTRR state, making it WB by default as the kernel does for
Hyper-V guests.
Signed-off-by: Kirill A. Shutemov <[email protected]>
Suggested-by: Binbin Wu <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Tom Lendacky <[email protected]>
Reviewed-by: Juergen Gross <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
| -rw-r--r-- | arch/x86/kernel/kvm.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 263f8aed4e2c..21e9e4845354 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -37,6 +37,7 @@ #include <asm/apic.h> #include <asm/apicdef.h> #include <asm/hypervisor.h> +#include <asm/mtrr.h> #include <asm/tlb.h> #include <asm/cpuidle_haltpoll.h> #include <asm/ptrace.h> @@ -980,6 +981,9 @@ static void __init kvm_init_platform(void) } kvmclock_init(); x86_platform.apic_post_init = kvm_apic_init; + + /* Set WB as the default cache mode for SEV-SNP and TDX */ + mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK); } #if defined(CONFIG_AMD_MEM_ENCRYPT) |