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-rw-r--r--arch/x86/kernel/cpu/bugs.c87
-rw-r--r--arch/x86/kernel/cpu/common.c48
-rw-r--r--arch/x86/kernel/cpu/cpuid-deps.c6
3 files changed, 67 insertions, 74 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 96bd3ee83..3f38592ec 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -60,6 +60,8 @@ EXPORT_SYMBOL_GPL(x86_spec_ctrl_current);
u64 x86_pred_cmd __ro_after_init = PRED_CMD_IBPB;
EXPORT_SYMBOL_GPL(x86_pred_cmd);
+static u64 __ro_after_init x86_arch_cap_msr;
+
static DEFINE_MUTEX(spec_ctrl_mutex);
void (*x86_return_thunk)(void) __ro_after_init = &__x86_return_thunk;
@@ -143,6 +145,8 @@ void __init cpu_select_mitigations(void)
x86_spec_ctrl_base &= ~SPEC_CTRL_MITIGATIONS_MASK;
}
+ x86_arch_cap_msr = x86_read_arch_cap_msr();
+
/* Select the proper CPU mitigations before patching alternatives: */
spectre_v1_select_mitigation();
spectre_v2_select_mitigation();
@@ -300,8 +304,6 @@ static const char * const taa_strings[] = {
static void __init taa_select_mitigation(void)
{
- u64 ia32_cap;
-
if (!boot_cpu_has_bug(X86_BUG_TAA)) {
taa_mitigation = TAA_MITIGATION_OFF;
return;
@@ -340,9 +342,8 @@ static void __init taa_select_mitigation(void)
* On MDS_NO=1 CPUs if ARCH_CAP_TSX_CTRL_MSR is not set, microcode
* update is required.
*/
- ia32_cap = x86_read_arch_cap_msr();
- if ( (ia32_cap & ARCH_CAP_MDS_NO) &&
- !(ia32_cap & ARCH_CAP_TSX_CTRL_MSR))
+ if ( (x86_arch_cap_msr & ARCH_CAP_MDS_NO) &&
+ !(x86_arch_cap_msr & ARCH_CAP_TSX_CTRL_MSR))
taa_mitigation = TAA_MITIGATION_UCODE_NEEDED;
/*
@@ -400,8 +401,6 @@ static const char * const mmio_strings[] = {
static void __init mmio_select_mitigation(void)
{
- u64 ia32_cap;
-
if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA) ||
boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN) ||
cpu_mitigations_off()) {
@@ -412,8 +411,6 @@ static void __init mmio_select_mitigation(void)
if (mmio_mitigation == MMIO_MITIGATION_OFF)
return;
- ia32_cap = x86_read_arch_cap_msr();
-
/*
* Enable CPU buffer clear mitigation for host and VMM, if also affected
* by MDS or TAA. Otherwise, enable mitigation for VMM only.
@@ -436,7 +433,7 @@ static void __init mmio_select_mitigation(void)
* be propagated to uncore buffers, clearing the Fill buffers on idle
* is required irrespective of SMT state.
*/
- if (!(ia32_cap & ARCH_CAP_FBSDP_NO))
+ if (!(x86_arch_cap_msr & ARCH_CAP_FBSDP_NO))
static_branch_enable(&mds_idle_clear);
/*
@@ -446,10 +443,10 @@ static void __init mmio_select_mitigation(void)
* FB_CLEAR or by the presence of both MD_CLEAR and L1D_FLUSH on MDS
* affected systems.
*/
- if ((ia32_cap & ARCH_CAP_FB_CLEAR) ||
+ if ((x86_arch_cap_msr & ARCH_CAP_FB_CLEAR) ||
(boot_cpu_has(X86_FEATURE_MD_CLEAR) &&
boot_cpu_has(X86_FEATURE_FLUSH_L1D) &&
- !(ia32_cap & ARCH_CAP_MDS_NO)))
+ !(x86_arch_cap_msr & ARCH_CAP_MDS_NO)))
mmio_mitigation = MMIO_MITIGATION_VERW;
else
mmio_mitigation = MMIO_MITIGATION_UCODE_NEEDED;
@@ -507,7 +504,7 @@ static void __init rfds_select_mitigation(void)
if (rfds_mitigation == RFDS_MITIGATION_OFF)
return;
- if (x86_read_arch_cap_msr() & ARCH_CAP_RFDS_CLEAR)
+ if (x86_arch_cap_msr & ARCH_CAP_RFDS_CLEAR)
setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF);
else
rfds_mitigation = RFDS_MITIGATION_UCODE_NEEDED;
@@ -658,8 +655,6 @@ void update_srbds_msr(void)
static void __init srbds_select_mitigation(void)
{
- u64 ia32_cap;
-
if (!boot_cpu_has_bug(X86_BUG_SRBDS))
return;
@@ -668,8 +663,7 @@ static void __init srbds_select_mitigation(void)
* are only exposed to SRBDS when TSX is enabled or when CPU is affected
* by Processor MMIO Stale Data vulnerability.
*/
- ia32_cap = x86_read_arch_cap_msr();
- if ((ia32_cap & ARCH_CAP_MDS_NO) && !boot_cpu_has(X86_FEATURE_RTM) &&
+ if ((x86_arch_cap_msr & ARCH_CAP_MDS_NO) && !boot_cpu_has(X86_FEATURE_RTM) &&
!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA))
srbds_mitigation = SRBDS_MITIGATION_TSX_OFF;
else if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
@@ -812,7 +806,7 @@ static void __init gds_select_mitigation(void)
/* Will verify below that mitigation _can_ be disabled */
/* No microcode */
- if (!(x86_read_arch_cap_msr() & ARCH_CAP_GDS_CTRL)) {
+ if (!(x86_arch_cap_msr & ARCH_CAP_GDS_CTRL)) {
if (gds_mitigation == GDS_MITIGATION_FORCE) {
/*
* This only needs to be done on the boot CPU so do it
@@ -1521,20 +1515,25 @@ static enum spectre_v2_mitigation __init spectre_v2_select_retpoline(void)
return SPECTRE_V2_RETPOLINE;
}
+static bool __ro_after_init rrsba_disabled;
+
/* Disable in-kernel use of non-RSB RET predictors */
static void __init spec_ctrl_disable_kernel_rrsba(void)
{
- u64 ia32_cap;
+ if (rrsba_disabled)
+ return;
- if (!boot_cpu_has(X86_FEATURE_RRSBA_CTRL))
+ if (!(x86_arch_cap_msr & ARCH_CAP_RRSBA)) {
+ rrsba_disabled = true;
return;
+ }
- ia32_cap = x86_read_arch_cap_msr();
+ if (!boot_cpu_has(X86_FEATURE_RRSBA_CTRL))
+ return;
- if (ia32_cap & ARCH_CAP_RRSBA) {
- x86_spec_ctrl_base |= SPEC_CTRL_RRSBA_DIS_S;
- update_spec_ctrl(x86_spec_ctrl_base);
- }
+ x86_spec_ctrl_base |= SPEC_CTRL_RRSBA_DIS_S;
+ update_spec_ctrl(x86_spec_ctrl_base);
+ rrsba_disabled = true;
}
static void __init spectre_v2_determine_rsb_fill_type_at_vmexit(enum spectre_v2_mitigation mode)
@@ -1603,13 +1602,10 @@ static bool __init spec_ctrl_bhi_dis(void)
enum bhi_mitigations {
BHI_MITIGATION_OFF,
BHI_MITIGATION_ON,
- BHI_MITIGATION_AUTO,
};
static enum bhi_mitigations bhi_mitigation __ro_after_init =
- IS_ENABLED(CONFIG_SPECTRE_BHI_ON) ? BHI_MITIGATION_ON :
- IS_ENABLED(CONFIG_SPECTRE_BHI_OFF) ? BHI_MITIGATION_OFF :
- BHI_MITIGATION_AUTO;
+ IS_ENABLED(CONFIG_MITIGATION_SPECTRE_BHI) ? BHI_MITIGATION_ON : BHI_MITIGATION_OFF;
static int __init spectre_bhi_parse_cmdline(char *str)
{
@@ -1620,8 +1616,6 @@ static int __init spectre_bhi_parse_cmdline(char *str)
bhi_mitigation = BHI_MITIGATION_OFF;
else if (!strcmp(str, "on"))
bhi_mitigation = BHI_MITIGATION_ON;
- else if (!strcmp(str, "auto"))
- bhi_mitigation = BHI_MITIGATION_AUTO;
else
pr_err("Ignoring unknown spectre_bhi option (%s)", str);
@@ -1635,9 +1629,12 @@ static void __init bhi_select_mitigation(void)
return;
/* Retpoline mitigates against BHI unless the CPU has RRSBA behavior */
- if (cpu_feature_enabled(X86_FEATURE_RETPOLINE) &&
- !(x86_read_arch_cap_msr() & ARCH_CAP_RRSBA))
- return;
+ if (boot_cpu_has(X86_FEATURE_RETPOLINE) &&
+ !boot_cpu_has(X86_FEATURE_RETPOLINE_LFENCE)) {
+ spec_ctrl_disable_kernel_rrsba();
+ if (rrsba_disabled)
+ return;
+ }
if (spec_ctrl_bhi_dis())
return;
@@ -1649,9 +1646,6 @@ static void __init bhi_select_mitigation(void)
setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT);
pr_info("Spectre BHI mitigation: SW BHB clearing on vm exit\n");
- if (bhi_mitigation == BHI_MITIGATION_AUTO)
- return;
-
/* Mitigate syscalls when the mitigation is forced =on */
setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP);
pr_info("Spectre BHI mitigation: SW BHB clearing on syscall\n");
@@ -1884,8 +1878,6 @@ static void update_indir_branch_cond(void)
/* Update the static key controlling the MDS CPU buffer clear in idle */
static void update_mds_branch_idle(void)
{
- u64 ia32_cap = x86_read_arch_cap_msr();
-
/*
* Enable the idle clearing if SMT is active on CPUs which are
* affected only by MSBDS and not any other MDS variant.
@@ -1900,7 +1892,7 @@ static void update_mds_branch_idle(void)
if (sched_smt_active()) {
static_branch_enable(&mds_idle_clear);
} else if (mmio_mitigation == MMIO_MITIGATION_OFF ||
- (ia32_cap & ARCH_CAP_FBSDP_NO)) {
+ (x86_arch_cap_msr & ARCH_CAP_FBSDP_NO)) {
static_branch_disable(&mds_idle_clear);
}
}
@@ -2788,21 +2780,22 @@ static char *pbrsb_eibrs_state(void)
}
}
-static const char * const spectre_bhi_state(void)
+static const char *spectre_bhi_state(void)
{
if (!boot_cpu_has_bug(X86_BUG_BHI))
return "; BHI: Not affected";
- else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_HW))
+ else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_HW))
return "; BHI: BHI_DIS_S";
- else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP))
+ else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP))
return "; BHI: SW loop, KVM: SW loop";
else if (boot_cpu_has(X86_FEATURE_RETPOLINE) &&
- !(x86_read_arch_cap_msr() & ARCH_CAP_RRSBA))
+ !boot_cpu_has(X86_FEATURE_RETPOLINE_LFENCE) &&
+ rrsba_disabled)
return "; BHI: Retpoline";
- else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT))
- return "; BHI: Syscall hardening, KVM: SW loop";
+ else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT))
+ return "; BHI: Vulnerable, KVM: SW loop";
- return "; BHI: Vulnerable (Syscall hardening enabled)";
+ return "; BHI: Vulnerable";
}
static ssize_t spectre_v2_show_state(char *buf)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 08fe77d2a..f2bc651c0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1308,25 +1308,25 @@ static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long whi
u64 x86_read_arch_cap_msr(void)
{
- u64 ia32_cap = 0;
+ u64 x86_arch_cap_msr = 0;
if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
- rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
+ rdmsrl(MSR_IA32_ARCH_CAPABILITIES, x86_arch_cap_msr);
- return ia32_cap;
+ return x86_arch_cap_msr;
}
-static bool arch_cap_mmio_immune(u64 ia32_cap)
+static bool arch_cap_mmio_immune(u64 x86_arch_cap_msr)
{
- return (ia32_cap & ARCH_CAP_FBSDP_NO &&
- ia32_cap & ARCH_CAP_PSDP_NO &&
- ia32_cap & ARCH_CAP_SBDR_SSDP_NO);
+ return (x86_arch_cap_msr & ARCH_CAP_FBSDP_NO &&
+ x86_arch_cap_msr & ARCH_CAP_PSDP_NO &&
+ x86_arch_cap_msr & ARCH_CAP_SBDR_SSDP_NO);
}
-static bool __init vulnerable_to_rfds(u64 ia32_cap)
+static bool __init vulnerable_to_rfds(u64 x86_arch_cap_msr)
{
/* The "immunity" bit trumps everything else: */
- if (ia32_cap & ARCH_CAP_RFDS_NO)
+ if (x86_arch_cap_msr & ARCH_CAP_RFDS_NO)
return false;
/*
@@ -1334,7 +1334,7 @@ static bool __init vulnerable_to_rfds(u64 ia32_cap)
* indicate that mitigation is needed because guest is running on a
* vulnerable hardware or may migrate to such hardware:
*/
- if (ia32_cap & ARCH_CAP_RFDS_CLEAR)
+ if (x86_arch_cap_msr & ARCH_CAP_RFDS_CLEAR)
return true;
/* Only consult the blacklist when there is no enumeration: */
@@ -1343,11 +1343,11 @@ static bool __init vulnerable_to_rfds(u64 ia32_cap)
static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
{
- u64 ia32_cap = x86_read_arch_cap_msr();
+ u64 x86_arch_cap_msr = x86_read_arch_cap_msr();
/* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */
if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) &&
- !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
+ !(x86_arch_cap_msr & ARCH_CAP_PSCHANGE_MC_NO))
setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT);
if (cpu_matches(cpu_vuln_whitelist, NO_SPECULATION))
@@ -1359,7 +1359,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
if (!cpu_matches(cpu_vuln_whitelist, NO_SSB) &&
- !(ia32_cap & ARCH_CAP_SSB_NO) &&
+ !(x86_arch_cap_msr & ARCH_CAP_SSB_NO) &&
!cpu_has(c, X86_FEATURE_AMD_SSB_NO))
setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
@@ -1367,15 +1367,15 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
* AMD's AutoIBRS is equivalent to Intel's eIBRS - use the Intel feature
* flag and protect from vendor-specific bugs via the whitelist.
*/
- if ((ia32_cap & ARCH_CAP_IBRS_ALL) || cpu_has(c, X86_FEATURE_AUTOIBRS)) {
+ if ((x86_arch_cap_msr & ARCH_CAP_IBRS_ALL) || cpu_has(c, X86_FEATURE_AUTOIBRS)) {
setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
if (!cpu_matches(cpu_vuln_whitelist, NO_EIBRS_PBRSB) &&
- !(ia32_cap & ARCH_CAP_PBRSB_NO))
+ !(x86_arch_cap_msr & ARCH_CAP_PBRSB_NO))
setup_force_cpu_bug(X86_BUG_EIBRS_PBRSB);
}
if (!cpu_matches(cpu_vuln_whitelist, NO_MDS) &&
- !(ia32_cap & ARCH_CAP_MDS_NO)) {
+ !(x86_arch_cap_msr & ARCH_CAP_MDS_NO)) {
setup_force_cpu_bug(X86_BUG_MDS);
if (cpu_matches(cpu_vuln_whitelist, MSBDS_ONLY))
setup_force_cpu_bug(X86_BUG_MSBDS_ONLY);
@@ -1394,9 +1394,9 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
* TSX_CTRL check alone is not sufficient for cases when the microcode
* update is not present or running as guest that don't get TSX_CTRL.
*/
- if (!(ia32_cap & ARCH_CAP_TAA_NO) &&
+ if (!(x86_arch_cap_msr & ARCH_CAP_TAA_NO) &&
(cpu_has(c, X86_FEATURE_RTM) ||
- (ia32_cap & ARCH_CAP_TSX_CTRL_MSR)))
+ (x86_arch_cap_msr & ARCH_CAP_TSX_CTRL_MSR)))
setup_force_cpu_bug(X86_BUG_TAA);
/*
@@ -1422,7 +1422,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
* Set X86_BUG_MMIO_UNKNOWN for CPUs that are neither in the blacklist,
* nor in the whitelist and also don't enumerate MSR ARCH_CAP MMIO bits.
*/
- if (!arch_cap_mmio_immune(ia32_cap)) {
+ if (!arch_cap_mmio_immune(x86_arch_cap_msr)) {
if (cpu_matches(cpu_vuln_blacklist, MMIO))
setup_force_cpu_bug(X86_BUG_MMIO_STALE_DATA);
else if (!cpu_matches(cpu_vuln_whitelist, NO_MMIO))
@@ -1430,7 +1430,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
}
if (!cpu_has(c, X86_FEATURE_BTC_NO)) {
- if (cpu_matches(cpu_vuln_blacklist, RETBLEED) || (ia32_cap & ARCH_CAP_RSBA))
+ if (cpu_matches(cpu_vuln_blacklist, RETBLEED) || (x86_arch_cap_msr & ARCH_CAP_RSBA))
setup_force_cpu_bug(X86_BUG_RETBLEED);
}
@@ -1443,7 +1443,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
* disabling AVX2. The only way to do this in HW is to clear XCR0[2],
* which means that AVX will be disabled.
*/
- if (cpu_matches(cpu_vuln_blacklist, GDS) && !(ia32_cap & ARCH_CAP_GDS_NO) &&
+ if (cpu_matches(cpu_vuln_blacklist, GDS) && !(x86_arch_cap_msr & ARCH_CAP_GDS_NO) &&
boot_cpu_has(X86_FEATURE_AVX))
setup_force_cpu_bug(X86_BUG_GDS);
@@ -1452,11 +1452,11 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_SRSO);
}
- if (vulnerable_to_rfds(ia32_cap))
+ if (vulnerable_to_rfds(x86_arch_cap_msr))
setup_force_cpu_bug(X86_BUG_RFDS);
/* When virtualized, eIBRS could be hidden, assume vulnerable */
- if (!(ia32_cap & ARCH_CAP_BHI_NO) &&
+ if (!(x86_arch_cap_msr & ARCH_CAP_BHI_NO) &&
!cpu_matches(cpu_vuln_whitelist, NO_BHI) &&
(boot_cpu_has(X86_FEATURE_IBRS_ENHANCED) ||
boot_cpu_has(X86_FEATURE_HYPERVISOR)))
@@ -1466,7 +1466,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
return;
/* Rogue Data Cache Load? No! */
- if (ia32_cap & ARCH_CAP_RDCL_NO)
+ if (x86_arch_cap_msr & ARCH_CAP_RDCL_NO)
return;
setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
index c881bcafb..9c19f40b1 100644
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -44,7 +44,10 @@ static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_F16C, X86_FEATURE_XMM2, },
{ X86_FEATURE_AES, X86_FEATURE_XMM2 },
{ X86_FEATURE_SHA_NI, X86_FEATURE_XMM2 },
+ { X86_FEATURE_GFNI, X86_FEATURE_XMM2 },
{ X86_FEATURE_FMA, X86_FEATURE_AVX },
+ { X86_FEATURE_VAES, X86_FEATURE_AVX },
+ { X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX },
{ X86_FEATURE_AVX2, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512F, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512IFMA, X86_FEATURE_AVX512F },
@@ -56,9 +59,6 @@ static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_AVX512VL, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512VBMI, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_VBMI2, X86_FEATURE_AVX512VL },
- { X86_FEATURE_GFNI, X86_FEATURE_AVX512VL },
- { X86_FEATURE_VAES, X86_FEATURE_AVX512VL },
- { X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_VNNI, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_BITALG, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_4VNNIW, X86_FEATURE_AVX512F },
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-02 23:16:38 +0000