diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/generic.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/mtrr.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/kvm.c | 21 | ||||
| -rw-r--r-- | arch/x86/kernel/umip.c | 15 |
4 files changed, 36 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c index 1ececfce7a46..4b1e2d14e5aa 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -423,7 +423,7 @@ void __init mtrr_copy_map(void) } /** - * mtrr_overwrite_state - set static MTRR state + * guest_force_mtrr_state - set static MTRR state for a guest * * Used to set MTRR state via different means (e.g. with data obtained from * a hypervisor). @@ -436,8 +436,8 @@ void __init mtrr_copy_map(void) * @num_var: length of the @var array * @def_type: default caching type */ -void mtrr_overwrite_state(struct mtrr_var_range *var, unsigned int num_var, - mtrr_type def_type) +void guest_force_mtrr_state(struct mtrr_var_range *var, unsigned int num_var, + mtrr_type def_type) { unsigned int i; diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c index 989d368be04f..ecbda0341a8a 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.c +++ b/arch/x86/kernel/cpu/mtrr/mtrr.c @@ -625,7 +625,7 @@ void mtrr_save_state(void) static int __init mtrr_init_finalize(void) { /* - * Map might exist if mtrr_overwrite_state() has been called or if + * Map might exist if guest_force_mtrr_state() has been called or if * mtrr_enabled() returns true. */ mtrr_copy_map(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 21e9e4845354..bd21c568bc2a 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -933,6 +933,19 @@ static void kvm_sev_hc_page_enc_status(unsigned long pfn, int npages, bool enc) static void __init kvm_init_platform(void) { + u64 tolud = PFN_PHYS(e820__end_of_low_ram_pfn()); + /* + * Note, hardware requires variable MTRR ranges to be power-of-2 sized + * and naturally aligned. But when forcing guest MTRR state, Linux + * doesn't program the forced ranges into hardware. Don't bother doing + * the math to generate a technically-legal range. + */ + struct mtrr_var_range pci_hole = { + .base_lo = tolud | X86_MEMTYPE_UC, + .mask_lo = (u32)(~(SZ_4G - tolud - 1)) | MTRR_PHYSMASK_V, + .mask_hi = (BIT_ULL(boot_cpu_data.x86_phys_bits) - 1) >> 32, + }; + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && kvm_para_has_feature(KVM_FEATURE_MIGRATION_CONTROL)) { unsigned long nr_pages; @@ -982,8 +995,12 @@ 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); + /* + * Set WB as the default cache mode for SEV-SNP and TDX, with a single + * UC range for the legacy PCI hole, e.g. so that devices that expect + * to get UC/WC mappings don't get surprised with WB. + */ + guest_force_mtrr_state(&pci_hole, 1, MTRR_TYPE_WRBACK); } #if defined(CONFIG_AMD_MEM_ENCRYPT) diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index 5a4b21389b1d..d432f3824f0c 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -156,15 +156,26 @@ static int identify_insn(struct insn *insn) if (!insn->modrm.nbytes) return -EINVAL; - /* All the instructions of interest start with 0x0f. */ - if (insn->opcode.bytes[0] != 0xf) + /* The instructions of interest have 2-byte opcodes: 0F 00 or 0F 01. */ + if (insn->opcode.nbytes < 2 || insn->opcode.bytes[0] != 0xf) return -EINVAL; if (insn->opcode.bytes[1] == 0x1) { switch (X86_MODRM_REG(insn->modrm.value)) { case 0: + /* The reg form of 0F 01 /0 encodes VMX instructions. */ + if (X86_MODRM_MOD(insn->modrm.value) == 3) + return -EINVAL; + return UMIP_INST_SGDT; case 1: + /* + * The reg form of 0F 01 /1 encodes MONITOR/MWAIT, + * STAC/CLAC, and ENCLS. + */ + if (X86_MODRM_MOD(insn->modrm.value) == 3) + return -EINVAL; + return UMIP_INST_SIDT; case 4: return UMIP_INST_SMSW; |