diff options
author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2024-10-15 12:58:17 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-10-20 07:07:02 -0400 |
commit | 8e690b817e38769dc2fa0e7473e5a5dc1fc25795 (patch) | |
tree | bbe51d126b176306c2f51dba5520354cea20a058 /arch/x86 | |
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 <kirill.shutemov@linux.intel.com>
Suggested-by: Binbin Wu <binbin.wu@intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Message-ID: <20241015095818.357915-1-kirill.shutemov@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
-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) |