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Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c178
1 files changed, 108 insertions, 70 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 80710a68ef7d..e3a65e9fc750 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -18,12 +18,16 @@
#include <linux/init.h>
#include <linux/kprobes.h>
#include <linux/kgdb.h>
+#include <linux/mem_encrypt.h>
#include <linux/smp.h>
+#include <linux/cpu.h>
#include <linux/io.h>
#include <linux/syscore_ops.h>
#include <linux/pgtable.h>
#include <linux/stackprotector.h>
+#include <linux/utsname.h>
+#include <asm/alternative.h>
#include <asm/cmdline.h>
#include <asm/perf_event.h>
#include <asm/mmu_context.h>
@@ -59,7 +63,7 @@
#include <asm/intel-family.h>
#include <asm/cpu_device_id.h>
#include <asm/uv/uv.h>
-#include <asm/sigframe.h>
+#include <asm/set_memory.h>
#include <asm/traps.h>
#include <asm/sev.h>
@@ -67,14 +71,6 @@
u32 elf_hwcap2 __read_mostly;
-/* all of these masks are initialized in setup_cpu_local_masks() */
-cpumask_var_t cpu_initialized_mask;
-cpumask_var_t cpu_callout_mask;
-cpumask_var_t cpu_callin_mask;
-
-/* representing cpus for which sibling maps can be computed */
-cpumask_var_t cpu_sibling_setup_mask;
-
/* Number of siblings per CPU package */
int smp_num_siblings = 1;
EXPORT_SYMBOL(smp_num_siblings);
@@ -169,15 +165,6 @@ clear_ppin:
clear_cpu_cap(c, info->feature);
}
-/* correctly size the local cpu masks */
-void __init setup_cpu_local_masks(void)
-{
- alloc_bootmem_cpumask_var(&cpu_initialized_mask);
- alloc_bootmem_cpumask_var(&cpu_callin_mask);
- alloc_bootmem_cpumask_var(&cpu_callout_mask);
- alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
-}
-
static void default_init(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_64
@@ -1263,6 +1250,10 @@ 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),
@@ -1275,27 +1266,30 @@ 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),
{}
};
@@ -1419,6 +1413,21 @@ 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;
@@ -1502,12 +1511,10 @@ static void __init cpu_parse_early_param(void)
if (!kstrtouint(opt, 10, &bit)) {
if (bit < NCAPINTS * 32) {
-#ifdef CONFIG_X86_FEATURE_NAMES
/* empty-string, i.e., ""-defined feature flags */
if (!x86_cap_flags[bit])
pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit));
else
-#endif
pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit));
setup_clear_cpu_cap(bit);
@@ -1520,7 +1527,6 @@ static void __init cpu_parse_early_param(void)
continue;
}
-#ifdef CONFIG_X86_FEATURE_NAMES
for (bit = 0; bit < 32 * NCAPINTS; bit++) {
if (!x86_cap_flag(bit))
continue;
@@ -1537,7 +1543,6 @@ static void __init cpu_parse_early_param(void)
if (!found)
pr_cont(" (unknown: %s)", opt);
-#endif
}
pr_cont("\n");
@@ -1600,10 +1605,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
sld_setup(c);
- fpu__init_system(c);
-
- init_sigframe_size();
-
#ifdef CONFIG_X86_32
/*
* Regardless of whether PCID is enumerated, the SDM says
@@ -1983,6 +1984,8 @@ 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();
}
@@ -2123,19 +2126,6 @@ static void dbg_restore_debug_regs(void)
#define dbg_restore_debug_regs()
#endif /* ! CONFIG_KGDB */
-static void wait_for_master_cpu(int cpu)
-{
-#ifdef CONFIG_SMP
- /*
- * wait for ACK from master CPU before continuing
- * with AP initialization
- */
- WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask));
- while (!cpumask_test_cpu(cpu, cpu_callout_mask))
- cpu_relax();
-#endif
-}
-
static inline void setup_getcpu(int cpu)
{
unsigned long cpudata = vdso_encode_cpunode(cpu, early_cpu_to_node(cpu));
@@ -2158,11 +2148,7 @@ static inline void setup_getcpu(int cpu)
}
#ifdef CONFIG_X86_64
-static inline void ucode_cpu_init(int cpu)
-{
- if (cpu)
- load_ucode_ap();
-}
+static inline void ucode_cpu_init(int cpu) { }
static inline void tss_setup_ist(struct tss_struct *tss)
{
@@ -2239,8 +2225,6 @@ void cpu_init(void)
struct task_struct *cur = current;
int cpu = raw_smp_processor_id();
- wait_for_master_cpu(cpu);
-
ucode_cpu_init(cpu);
#ifdef CONFIG_NUMA
@@ -2285,26 +2269,12 @@ void cpu_init(void)
doublefault_init_cpu_tss();
- fpu__init_cpu();
-
if (is_uv_system())
uv_cpu_init();
load_fixmap_gdt(cpu);
}
-#ifdef CONFIG_SMP
-void cpu_init_secondary(void)
-{
- /*
- * Relies on the BP having set-up the IDT tables, which are loaded
- * on this CPU in cpu_init_exception_handling().
- */
- cpu_init_exception_handling();
- cpu_init();
-}
-#endif
-
#ifdef CONFIG_MICROCODE_LATE_LOADING
/**
* store_cpu_caps() - Store a snapshot of CPU capabilities
@@ -2341,6 +2311,8 @@ void microcode_check(struct cpuinfo_x86 *prev_info)
perf_check_microcode();
+ amd_check_microcode();
+
store_cpu_caps(&curr_info);
if (!memcmp(&prev_info->x86_capability, &curr_info.x86_capability,
@@ -2362,3 +2334,69 @@ void arch_smt_update(void)
/* Check whether IPI broadcasting can be enabled */
apic_smt_update();
}
+
+void __init arch_cpu_finalize_init(void)
+{
+ identify_boot_cpu();
+
+ /*
+ * identify_boot_cpu() initialized SMT support information, let the
+ * core code know.
+ */
+ cpu_smt_check_topology();
+
+ if (!IS_ENABLED(CONFIG_SMP)) {
+ pr_info("CPU: ");
+ print_cpu_info(&boot_cpu_data);
+ }
+
+ cpu_select_mitigations();
+
+ arch_smt_update();
+
+ if (IS_ENABLED(CONFIG_X86_32)) {
+ /*
+ * Check whether this is a real i386 which is not longer
+ * supported and fixup the utsname.
+ */
+ if (boot_cpu_data.x86 < 4)
+ panic("Kernel requires i486+ for 'invlpg' and other features");
+
+ init_utsname()->machine[1] =
+ '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86);
+ }
+
+ /*
+ * Must be before alternatives because it might set or clear
+ * feature bits.
+ */
+ fpu__init_system();
+ fpu__init_cpu();
+
+ alternative_instructions();
+
+ if (IS_ENABLED(CONFIG_X86_64)) {
+ /*
+ * Make sure the first 2MB area is not mapped by huge pages
+ * There are typically fixed size MTRRs in there and overlapping
+ * MTRRs into large pages causes slow downs.
+ *
+ * Right now we don't do that with gbpages because there seems
+ * very little benefit for that case.
+ */
+ if (!direct_gbpages)
+ set_memory_4k((unsigned long)__va(0), 1);
+ } else {
+ fpu__init_check_bugs();
+ }
+
+ /*
+ * This needs to be called before any devices perform DMA
+ * operations that might use the SWIOTLB bounce buffers. It will
+ * mark the bounce buffers as decrypted so that their usage will
+ * not cause "plain-text" data to be decrypted when accessed. It
+ * must be called after late_time_init() so that Hyper-V x86/x64
+ * hypercalls work when the SWIOTLB bounce buffers are decrypted.
+ */
+ mem_encrypt_init();
+}