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-rw-r--r--arch/x86/kernel/acpi/boot.c4
-rw-r--r--arch/x86/kernel/alternative.c5
-rw-r--r--arch/x86/kernel/amd_nb.c8
-rw-r--r--arch/x86/kernel/apic/ipi.c2
-rw-r--r--arch/x86/kernel/apic/x2apic_uv_x.c5
-rw-r--r--arch/x86/kernel/cpu/amd.c40
-rw-r--r--arch/x86/kernel/cpu/bugs.c356
-rw-r--r--arch/x86/kernel/cpu/common.c50
-rw-r--r--arch/x86/kernel/cpu/cpu.h1
-rw-r--r--arch/x86/kernel/cpu/intel.c176
-rw-r--r--arch/x86/kernel/cpu/intel_epb.c2
-rw-r--r--arch/x86/kernel/cpu/mce/core.c35
-rw-r--r--arch/x86/kernel/cpu/mce/intel.c19
-rw-r--r--arch/x86/kernel/cpu/mce/internal.h6
-rw-r--r--arch/x86/kernel/cpu/microcode/Makefile4
-rw-r--r--arch/x86/kernel/cpu/microcode/amd.c133
-rw-r--r--arch/x86/kernel/cpu/microcode/core.c17
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c304
-rw-r--r--arch/x86/kernel/cpu/microcode/internal.h131
-rw-r--r--arch/x86/kernel/fpu/context.h3
-rw-r--r--arch/x86/kernel/fpu/core.c2
-rw-r--r--arch/x86/kernel/fpu/xstate.c7
-rw-r--r--arch/x86/kernel/head_64.S32
-rw-r--r--arch/x86/kernel/hpet.c2
-rw-r--r--arch/x86/kernel/kprobes/opt.c40
-rw-r--r--arch/x86/kernel/kvm.c4
-rw-r--r--arch/x86/kernel/paravirt.c11
-rw-r--r--arch/x86/kernel/sev.c6
-rw-r--r--arch/x86/kernel/smpboot.c19
-rw-r--r--arch/x86/kernel/static_call.c13
-rw-r--r--arch/x86/kernel/tsc.c2
-rw-r--r--arch/x86/kernel/vmlinux.lds.S37
32 files changed, 1024 insertions, 452 deletions
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 21b542a6866c..53369c57751e 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -52,6 +52,7 @@ int acpi_lapic;
int acpi_ioapic;
int acpi_strict;
int acpi_disable_cmcff;
+bool acpi_int_src_ovr[NR_IRQS_LEGACY];
/* ACPI SCI override configuration */
u8 acpi_sci_flags __initdata;
@@ -588,6 +589,9 @@ acpi_parse_int_src_ovr(union acpi_subtable_headers * header,
acpi_table_print_madt_entry(&header->common);
+ if (intsrc->source_irq < NR_IRQS_LEGACY)
+ acpi_int_src_ovr[intsrc->source_irq] = true;
+
if (intsrc->source_irq == acpi_gbl_FADT.sci_interrupt) {
acpi_sci_ioapic_setup(intsrc->source_irq,
intsrc->inti_flags & ACPI_MADT_POLARITY_MASK,
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 2dcf3a06af09..a5ead6a6d233 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -687,10 +687,6 @@ void __init_or_module noinline apply_retpolines(s32 *start, s32 *end)
#ifdef CONFIG_RETHUNK
-#ifdef CONFIG_CALL_THUNKS
-void (*x86_return_thunk)(void) __ro_after_init = &__x86_return_thunk;
-#endif
-
/*
* Rewrite the compiler generated return thunk tail-calls.
*
@@ -1531,6 +1527,7 @@ static noinline void __init int3_selftest(void)
static __initdata int __alt_reloc_selftest_addr;
+extern void __init __alt_reloc_selftest(void *arg);
__visible noinline void __init __alt_reloc_selftest(void *arg)
{
WARN_ON(arg != &__alt_reloc_selftest_addr);
diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c
index 035a3db5330b..356de955e78d 100644
--- a/arch/x86/kernel/amd_nb.c
+++ b/arch/x86/kernel/amd_nb.c
@@ -24,6 +24,8 @@
#define PCI_DEVICE_ID_AMD_19H_M40H_ROOT 0x14b5
#define PCI_DEVICE_ID_AMD_19H_M60H_ROOT 0x14d8
#define PCI_DEVICE_ID_AMD_19H_M70H_ROOT 0x14e8
+#define PCI_DEVICE_ID_AMD_1AH_M00H_ROOT 0x153a
+#define PCI_DEVICE_ID_AMD_1AH_M20H_ROOT 0x1507
#define PCI_DEVICE_ID_AMD_MI200_ROOT 0x14bb
#define PCI_DEVICE_ID_AMD_17H_DF_F4 0x1464
@@ -39,6 +41,7 @@
#define PCI_DEVICE_ID_AMD_19H_M60H_DF_F4 0x14e4
#define PCI_DEVICE_ID_AMD_19H_M70H_DF_F4 0x14f4
#define PCI_DEVICE_ID_AMD_19H_M78H_DF_F4 0x12fc
+#define PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4 0x12c4
#define PCI_DEVICE_ID_AMD_MI200_DF_F4 0x14d4
/* Protect the PCI config register pairs used for SMN. */
@@ -56,6 +59,8 @@ static const struct pci_device_id amd_root_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_ROOT) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_ROOT) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_ROOT) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_ROOT) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_ROOT) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_ROOT) },
{}
};
@@ -85,6 +90,8 @@ static const struct pci_device_id amd_nb_misc_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F3) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F3) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_DF_F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F3) },
{}
};
@@ -106,6 +113,7 @@ static const struct pci_device_id amd_nb_link_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F4) },
{}
};
diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index 2a6509e8c840..9bfd6e397384 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -301,6 +301,7 @@ void default_send_IPI_mask_logical(const struct cpumask *cpumask, int vector)
local_irq_restore(flags);
}
+#ifdef CONFIG_SMP
/* must come after the send_IPI functions above for inlining */
static int convert_apicid_to_cpu(int apic_id)
{
@@ -329,3 +330,4 @@ int safe_smp_processor_id(void)
return cpuid >= 0 ? cpuid : 0;
}
#endif
+#endif
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d9384d5b4b8e..b524dee1cbbb 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -294,8 +294,7 @@ static void __init early_get_apic_socketid_shift(void)
static void __init uv_stringify(int len, char *to, char *from)
{
- /* Relies on 'to' being NULL chars so result will be NULL terminated */
- strncpy(to, from, len-1);
+ strscpy(to, from, len);
/* Trim trailing spaces */
(void)strim(to);
@@ -1013,7 +1012,7 @@ static void __init calc_mmioh_map(enum mmioh_arch index,
/* One (UV2) mapping */
if (index == UV2_MMIOH) {
- strncpy(id, "MMIOH", sizeof(id));
+ strscpy(id, "MMIOH", sizeof(id));
max_io = max_pnode;
mapped = 0;
goto map_exit;
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 26ad7ca423e7..7eca6a8abbb1 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -73,8 +73,13 @@ static const int amd_erratum_1054[] =
static const int amd_zenbleed[] =
AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
+ AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
+static const int amd_div0[] =
+ AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
+ AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
+
static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
{
int osvw_id = *erratum++;
@@ -1130,6 +1135,11 @@ static void init_amd(struct cpuinfo_x86 *c)
WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
zenbleed_check(c);
+
+ if (cpu_has_amd_erratum(c, amd_div0)) {
+ pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
+ setup_force_cpu_bug(X86_BUG_DIV0);
+ }
}
#ifdef CONFIG_X86_32
@@ -1290,3 +1300,33 @@ void amd_check_microcode(void)
{
on_each_cpu(zenbleed_check_cpu, NULL, 1);
}
+
+bool cpu_has_ibpb_brtype_microcode(void)
+{
+ switch (boot_cpu_data.x86) {
+ /* Zen1/2 IBPB flushes branch type predictions too. */
+ case 0x17:
+ return boot_cpu_has(X86_FEATURE_AMD_IBPB);
+ case 0x19:
+ /* Poke the MSR bit on Zen3/4 to check its presence. */
+ if (!wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
+ setup_force_cpu_cap(X86_FEATURE_SBPB);
+ return true;
+ } else {
+ return false;
+ }
+ default:
+ return false;
+ }
+}
+
+/*
+ * Issue a DIV 0/1 insn to clear any division data from previous DIV
+ * operations.
+ */
+void noinstr amd_clear_divider(void)
+{
+ asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
+ :: "a" (0), "d" (0), "r" (1));
+}
+EXPORT_SYMBOL_GPL(amd_clear_divider);
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 95507448e781..f081d26616ac 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -47,6 +47,8 @@ static void __init taa_select_mitigation(void);
static void __init mmio_select_mitigation(void);
static void __init srbds_select_mitigation(void);
static void __init l1d_flush_select_mitigation(void);
+static void __init srso_select_mitigation(void);
+static void __init gds_select_mitigation(void);
/* The base value of the SPEC_CTRL MSR without task-specific bits set */
u64 x86_spec_ctrl_base;
@@ -56,8 +58,13 @@ EXPORT_SYMBOL_GPL(x86_spec_ctrl_base);
DEFINE_PER_CPU(u64, x86_spec_ctrl_current);
EXPORT_SYMBOL_GPL(x86_spec_ctrl_current);
+u64 x86_pred_cmd __ro_after_init = PRED_CMD_IBPB;
+EXPORT_SYMBOL_GPL(x86_pred_cmd);
+
static DEFINE_MUTEX(spec_ctrl_mutex);
+void (*x86_return_thunk)(void) __ro_after_init = &__x86_return_thunk;
+
/* Update SPEC_CTRL MSR and its cached copy unconditionally */
static void update_spec_ctrl(u64 val)
{
@@ -160,6 +167,13 @@ void __init cpu_select_mitigations(void)
md_clear_select_mitigation();
srbds_select_mitigation();
l1d_flush_select_mitigation();
+
+ /*
+ * srso_select_mitigation() depends and must run after
+ * retbleed_select_mitigation().
+ */
+ srso_select_mitigation();
+ gds_select_mitigation();
}
/*
@@ -646,6 +660,149 @@ static int __init l1d_flush_parse_cmdline(char *str)
early_param("l1d_flush", l1d_flush_parse_cmdline);
#undef pr_fmt
+#define pr_fmt(fmt) "GDS: " fmt
+
+enum gds_mitigations {
+ GDS_MITIGATION_OFF,
+ GDS_MITIGATION_UCODE_NEEDED,
+ GDS_MITIGATION_FORCE,
+ GDS_MITIGATION_FULL,
+ GDS_MITIGATION_FULL_LOCKED,
+ GDS_MITIGATION_HYPERVISOR,
+};
+
+#if IS_ENABLED(CONFIG_GDS_FORCE_MITIGATION)
+static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FORCE;
+#else
+static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FULL;
+#endif
+
+static const char * const gds_strings[] = {
+ [GDS_MITIGATION_OFF] = "Vulnerable",
+ [GDS_MITIGATION_UCODE_NEEDED] = "Vulnerable: No microcode",
+ [GDS_MITIGATION_FORCE] = "Mitigation: AVX disabled, no microcode",
+ [GDS_MITIGATION_FULL] = "Mitigation: Microcode",
+ [GDS_MITIGATION_FULL_LOCKED] = "Mitigation: Microcode (locked)",
+ [GDS_MITIGATION_HYPERVISOR] = "Unknown: Dependent on hypervisor status",
+};
+
+bool gds_ucode_mitigated(void)
+{
+ return (gds_mitigation == GDS_MITIGATION_FULL ||
+ gds_mitigation == GDS_MITIGATION_FULL_LOCKED);
+}
+EXPORT_SYMBOL_GPL(gds_ucode_mitigated);
+
+void update_gds_msr(void)
+{
+ u64 mcu_ctrl_after;
+ u64 mcu_ctrl;
+
+ switch (gds_mitigation) {
+ case GDS_MITIGATION_OFF:
+ rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+ mcu_ctrl |= GDS_MITG_DIS;
+ break;
+ case GDS_MITIGATION_FULL_LOCKED:
+ /*
+ * The LOCKED state comes from the boot CPU. APs might not have
+ * the same state. Make sure the mitigation is enabled on all
+ * CPUs.
+ */
+ case GDS_MITIGATION_FULL:
+ rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+ mcu_ctrl &= ~GDS_MITG_DIS;
+ break;
+ case GDS_MITIGATION_FORCE:
+ case GDS_MITIGATION_UCODE_NEEDED:
+ case GDS_MITIGATION_HYPERVISOR:
+ return;
+ };
+
+ wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+
+ /*
+ * Check to make sure that the WRMSR value was not ignored. Writes to
+ * GDS_MITG_DIS will be ignored if this processor is locked but the boot
+ * processor was not.
+ */
+ rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl_after);
+ WARN_ON_ONCE(mcu_ctrl != mcu_ctrl_after);
+}
+
+static void __init gds_select_mitigation(void)
+{
+ u64 mcu_ctrl;
+
+ if (!boot_cpu_has_bug(X86_BUG_GDS))
+ return;
+
+ if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+ gds_mitigation = GDS_MITIGATION_HYPERVISOR;
+ goto out;
+ }
+
+ if (cpu_mitigations_off())
+ gds_mitigation = GDS_MITIGATION_OFF;
+ /* Will verify below that mitigation _can_ be disabled */
+
+ /* No microcode */
+ if (!(x86_read_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
+ * here rather than in update_gds_msr()
+ */
+ setup_clear_cpu_cap(X86_FEATURE_AVX);
+ pr_warn("Microcode update needed! Disabling AVX as mitigation.\n");
+ } else {
+ gds_mitigation = GDS_MITIGATION_UCODE_NEEDED;
+ }
+ goto out;
+ }
+
+ /* Microcode has mitigation, use it */
+ if (gds_mitigation == GDS_MITIGATION_FORCE)
+ gds_mitigation = GDS_MITIGATION_FULL;
+
+ rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+ if (mcu_ctrl & GDS_MITG_LOCKED) {
+ if (gds_mitigation == GDS_MITIGATION_OFF)
+ pr_warn("Mitigation locked. Disable failed.\n");
+
+ /*
+ * The mitigation is selected from the boot CPU. All other CPUs
+ * _should_ have the same state. If the boot CPU isn't locked
+ * but others are then update_gds_msr() will WARN() of the state
+ * mismatch. If the boot CPU is locked update_gds_msr() will
+ * ensure the other CPUs have the mitigation enabled.
+ */
+ gds_mitigation = GDS_MITIGATION_FULL_LOCKED;
+ }
+
+ update_gds_msr();
+out:
+ pr_info("%s\n", gds_strings[gds_mitigation]);
+}
+
+static int __init gds_parse_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!boot_cpu_has_bug(X86_BUG_GDS))
+ return 0;
+
+ if (!strcmp(str, "off"))
+ gds_mitigation = GDS_MITIGATION_OFF;
+ else if (!strcmp(str, "force"))
+ gds_mitigation = GDS_MITIGATION_FORCE;
+
+ return 0;
+}
+early_param("gather_data_sampling", gds_parse_cmdline);
+
+#undef pr_fmt
#define pr_fmt(fmt) "Spectre V1 : " fmt
enum spectre_v1_mitigation {
@@ -885,6 +1042,9 @@ do_cmd_auto:
setup_force_cpu_cap(X86_FEATURE_RETHUNK);
setup_force_cpu_cap(X86_FEATURE_UNRET);
+ if (IS_ENABLED(CONFIG_RETHUNK))
+ x86_return_thunk = retbleed_return_thunk;
+
if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
pr_err(RETBLEED_UNTRAIN_MSG);
@@ -894,6 +1054,7 @@ do_cmd_auto:
case RETBLEED_MITIGATION_IBPB:
setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB);
+ setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT);
mitigate_smt = true;
break;
@@ -2188,6 +2349,170 @@ static int __init l1tf_cmdline(char *str)
early_param("l1tf", l1tf_cmdline);
#undef pr_fmt
+#define pr_fmt(fmt) "Speculative Return Stack Overflow: " fmt
+
+enum srso_mitigation {
+ SRSO_MITIGATION_NONE,
+ SRSO_MITIGATION_MICROCODE,
+ SRSO_MITIGATION_SAFE_RET,
+ SRSO_MITIGATION_IBPB,
+ SRSO_MITIGATION_IBPB_ON_VMEXIT,
+};
+
+enum srso_mitigation_cmd {
+ SRSO_CMD_OFF,
+ SRSO_CMD_MICROCODE,
+ SRSO_CMD_SAFE_RET,
+ SRSO_CMD_IBPB,
+ SRSO_CMD_IBPB_ON_VMEXIT,
+};
+
+static const char * const srso_strings[] = {
+ [SRSO_MITIGATION_NONE] = "Vulnerable",
+ [SRSO_MITIGATION_MICROCODE] = "Mitigation: microcode",
+ [SRSO_MITIGATION_SAFE_RET] = "Mitigation: safe RET",
+ [SRSO_MITIGATION_IBPB] = "Mitigation: IBPB",
+ [SRSO_MITIGATION_IBPB_ON_VMEXIT] = "Mitigation: IBPB on VMEXIT only"
+};
+
+static enum srso_mitigation srso_mitigation __ro_after_init = SRSO_MITIGATION_NONE;
+static enum srso_mitigation_cmd srso_cmd __ro_after_init = SRSO_CMD_SAFE_RET;
+
+static int __init srso_parse_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!strcmp(str, "off"))
+ srso_cmd = SRSO_CMD_OFF;
+ else if (!strcmp(str, "microcode"))
+ srso_cmd = SRSO_CMD_MICROCODE;
+ else if (!strcmp(str, "safe-ret"))
+ srso_cmd = SRSO_CMD_SAFE_RET;
+ else if (!strcmp(str, "ibpb"))
+ srso_cmd = SRSO_CMD_IBPB;
+ else if (!strcmp(str, "ibpb-vmexit"))
+ srso_cmd = SRSO_CMD_IBPB_ON_VMEXIT;
+ else
+ pr_err("Ignoring unknown SRSO option (%s).", str);
+
+ return 0;
+}
+early_param("spec_rstack_overflow", srso_parse_cmdline);
+
+#define SRSO_NOTICE "WARNING: See https://kernel.org/doc/html/latest/admin-guide/hw-vuln/srso.html for mitigation options."
+
+static void __init srso_select_mitigation(void)
+{
+ bool has_microcode;
+
+ if (!boot_cpu_has_bug(X86_BUG_SRSO) || cpu_mitigations_off())
+ goto pred_cmd;
+
+ /*
+ * The first check is for the kernel running as a guest in order
+ * for guests to verify whether IBPB is a viable mitigation.
+ */
+ has_microcode = boot_cpu_has(X86_FEATURE_IBPB_BRTYPE) || cpu_has_ibpb_brtype_microcode();
+ if (!has_microcode) {
+ pr_warn("IBPB-extending microcode not applied!\n");
+ pr_warn(SRSO_NOTICE);
+ } else {
+ /*
+ * Enable the synthetic (even if in a real CPUID leaf)
+ * flags for guests.
+ */
+ setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
+
+ /*
+ * Zen1/2 with SMT off aren't vulnerable after the right
+ * IBPB microcode has been applied.
+ */
+ if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) {
+ setup_force_cpu_cap(X86_FEATURE_SRSO_NO);
+ return;
+ }
+ }
+
+ if (retbleed_mitigation == RETBLEED_MITIGATION_IBPB) {
+ if (has_microcode) {
+ pr_err("Retbleed IBPB mitigation enabled, using same for SRSO\n");
+ srso_mitigation = SRSO_MITIGATION_IBPB;
+ goto pred_cmd;
+ }
+ }
+
+ switch (srso_cmd) {
+ case SRSO_CMD_OFF:
+ return;
+
+ case SRSO_CMD_MICROCODE:
+ if (has_microcode) {
+ srso_mitigation = SRSO_MITIGATION_MICROCODE;
+ pr_warn(SRSO_NOTICE);
+ }
+ break;
+
+ case SRSO_CMD_SAFE_RET:
+ if (IS_ENABLED(CONFIG_CPU_SRSO)) {
+ /*
+ * Enable the return thunk for generated code
+ * like ftrace, static_call, etc.
+ */
+ setup_force_cpu_cap(X86_FEATURE_RETHUNK);
+ setup_force_cpu_cap(X86_FEATURE_UNRET);
+
+ if (boot_cpu_data.x86 == 0x19) {
+ setup_force_cpu_cap(X86_FEATURE_SRSO_ALIAS);
+ x86_return_thunk = srso_alias_return_thunk;
+ } else {
+ setup_force_cpu_cap(X86_FEATURE_SRSO);
+ x86_return_thunk = srso_return_thunk;
+ }
+ srso_mitigation = SRSO_MITIGATION_SAFE_RET;
+ } else {
+ pr_err("WARNING: kernel not compiled with CPU_SRSO.\n");
+ goto pred_cmd;
+ }
+ break;
+
+ case SRSO_CMD_IBPB:
+ if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) {
+ if (has_microcode) {
+ setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB);
+ srso_mitigation = SRSO_MITIGATION_IBPB;
+ }
+ } else {
+ pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n");
+ goto pred_cmd;
+ }
+ break;
+
+ case SRSO_CMD_IBPB_ON_VMEXIT:
+ if (IS_ENABLED(CONFIG_CPU_SRSO)) {
+ if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) {
+ setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT);
+ srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT;
+ }
+ } else {
+ pr_err("WARNING: kernel not compiled with CPU_SRSO.\n");
+ goto pred_cmd;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ pr_info("%s%s\n", srso_strings[srso_mitigation], (has_microcode ? "" : ", no microcode"));
+
+pred_cmd:
+ if ((boot_cpu_has(X86_FEATURE_SRSO_NO) || srso_cmd == SRSO_CMD_OFF) &&
+ boot_cpu_has(X86_FEATURE_SBPB))
+ x86_pred_cmd = PRED_CMD_SBPB;
+}
+
+#undef pr_fmt
#define pr_fmt(fmt) fmt
#ifdef CONFIG_SYSFS
@@ -2385,6 +2710,21 @@ static ssize_t retbleed_show_state(char *buf)
return sysfs_emit(buf, "%s\n", retbleed_strings[retbleed_mitigation]);
}
+static ssize_t srso_show_state(char *buf)
+{
+ if (boot_cpu_has(X86_FEATURE_SRSO_NO))
+ return sysfs_emit(buf, "Mitigation: SMT disabled\n");
+
+ return sysfs_emit(buf, "%s%s\n",
+ srso_strings[srso_mitigation],
+ (cpu_has_ibpb_brtype_microcode() ? "" : ", no microcode"));
+}
+
+static ssize_t gds_show_state(char *buf)
+{
+ return sysfs_emit(buf, "%s\n", gds_strings[gds_mitigation]);
+}
+
static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
char *buf, unsigned int bug)
{
@@ -2434,6 +2774,12 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
case X86_BUG_RETBLEED:
return retbleed_show_state(buf);
+ case X86_BUG_SRSO:
+ return srso_show_state(buf);
+
+ case X86_BUG_GDS:
+ return gds_show_state(buf);
+
default:
break;
}
@@ -2498,4 +2844,14 @@ ssize_t cpu_show_retbleed(struct device *dev, struct device_attribute *attr, cha
{
return cpu_show_common(dev, attr, buf, X86_BUG_RETBLEED);
}
+
+ssize_t cpu_show_spec_rstack_overflow(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_SRSO);
+}
+
+ssize_t cpu_show_gds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_GDS);
+}
#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 0ba1067f4e5f..41b573f34a10 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -59,7 +59,6 @@
#include <asm/cacheinfo.h>
#include <asm/memtype.h>
#include <asm/microcode.h>
-#include <asm/microcode_intel.h>
#include <asm/intel-family.h>
#include <asm/cpu_device_id.h>
#include <asm/uv/uv.h>
@@ -1250,6 +1249,10 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
#define RETBLEED BIT(3)
/* CPU is affected by SMT (cross-thread) return predictions */
#define SMT_RSB BIT(4)
+/* CPU is affected by SRSO */
+#define SRSO BIT(5)
+/* CPU is affected by GDS */
+#define GDS BIT(6)
static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS),
@@ -1262,27 +1265,30 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(BROADWELL_X, X86_STEPPING_ANY, MMIO),
VULNBL_INTEL_STEPPINGS(BROADWELL, X86_STEPPING_ANY, SRBDS),
VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
- VULNBL_INTEL_STEPPINGS(SKYLAKE_X, X86_STEPPING_ANY, MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE_X, X86_STEPPING_ANY, MMIO | RETBLEED | GDS),
VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
- VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
- VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED | GDS),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED | GDS),
VULNBL_INTEL_STEPPINGS(CANNONLAKE_L, X86_STEPPING_ANY, RETBLEED),
- VULNBL_INTEL_STEPPINGS(ICELAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
- VULNBL_INTEL_STEPPINGS(ICELAKE_D, X86_STEPPING_ANY, MMIO),
- VULNBL_INTEL_STEPPINGS(ICELAKE_X, X86_STEPPING_ANY, MMIO),
- VULNBL_INTEL_STEPPINGS(COMETLAKE, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED | GDS),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_D, X86_STEPPING_ANY, MMIO | GDS),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_X, X86_STEPPING_ANY, MMIO | GDS),
+ VULNBL_INTEL_STEPPINGS(COMETLAKE, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED | GDS),
VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED),
- VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED | GDS),
+ VULNBL_INTEL_STEPPINGS(TIGERLAKE_L, X86_STEPPING_ANY, GDS),
+ VULNBL_INTEL_STEPPINGS(TIGERLAKE, X86_STEPPING_ANY, GDS),
VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
- VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED | GDS),
VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO),
VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
VULNBL_AMD(0x15, RETBLEED),
VULNBL_AMD(0x16, RETBLEED),
- VULNBL_AMD(0x17, RETBLEED | SMT_RSB),
+ VULNBL_AMD(0x17, RETBLEED | SMT_RSB | SRSO),
VULNBL_HYGON(0x18, RETBLEED | SMT_RSB),
+ VULNBL_AMD(0x19, SRSO),
{}
};
@@ -1406,6 +1412,21 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
if (cpu_matches(cpu_vuln_blacklist, SMT_RSB))
setup_force_cpu_bug(X86_BUG_SMT_RSB);
+ if (!cpu_has(c, X86_FEATURE_SRSO_NO)) {
+ if (cpu_matches(cpu_vuln_blacklist, SRSO))
+ setup_force_cpu_bug(X86_BUG_SRSO);
+ }
+
+ /*
+ * Check if CPU is vulnerable to GDS. If running in a virtual machine on
+ * an affected processor, the VMM may have disabled the use of GATHER by
+ * 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) &&
+ boot_cpu_has(X86_FEATURE_AVX))
+ setup_force_cpu_bug(X86_BUG_GDS);
+
if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
return;
@@ -1962,6 +1983,8 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c)
validate_apic_and_package_id(c);
x86_spec_ctrl_setup_ap();
update_srbds_msr();
+ if (boot_cpu_has_bug(X86_BUG_GDS))
+ update_gds_msr();
tsx_ap_init();
}
@@ -2276,8 +2299,7 @@ void store_cpu_caps(struct cpuinfo_x86 *curr_info)
* @prev_info: CPU capabilities stored before an update.
*
* The microcode loader calls this upon late microcode load to recheck features,
- * only when microcode has been updated. Caller holds microcode_mutex and CPU
- * hotplug lock.
+ * only when microcode has been updated. Caller holds and CPU hotplug lock.
*
* Return: None
*/
@@ -2319,7 +2341,7 @@ void __init arch_cpu_finalize_init(void)
* identify_boot_cpu() initialized SMT support information, let the
* core code know.
*/
- cpu_smt_check_topology();
+ cpu_smt_set_num_threads(smp_num_siblings, smp_num_siblings);
if (!IS_ENABLED(CONFIG_SMP)) {
pr_info("CPU: ");
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 1c44630d4789..1dcd7d4e38ef 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -83,6 +83,7 @@ void cpu_select_mitigations(void);
extern void x86_spec_ctrl_setup_ap(void);
extern void update_srbds_msr(void);
+extern void update_gds_msr(void);
extern enum spectre_v2_mitigation spectre_v2_enabled;
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 1c4639588ff9..be4045628fd3 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -20,7 +20,7 @@
#include <asm/bugs.h>
#include <asm/cpu.h>
#include <asm/intel-family.h>
-#include <asm/microcode_intel.h>
+#include <asm/microcode.h>
#include <asm/hwcap2.h>
#include <asm/elf.h>
#include <asm/cpu_device_id.h>
@@ -184,180 +184,6 @@ static