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Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c284
1 files changed, 140 insertions, 144 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 9ae7d1bcd4f4..2e4d90294fe6 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -24,6 +24,7 @@
#include <asm/stackprotector.h>
#include <asm/perf_event.h>
#include <asm/mmu_context.h>
+#include <asm/doublefault.h>
#include <asm/archrandom.h>
#include <asm/hypervisor.h>
#include <asm/processor.h>
@@ -53,10 +54,7 @@
#include <asm/microcode_intel.h>
#include <asm/intel-family.h>
#include <asm/cpu_device_id.h>
-
-#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/uv/uv.h>
-#endif
#include "cpu.h"
@@ -565,8 +563,9 @@ static const char *table_lookup_model(struct cpuinfo_x86 *c)
return NULL; /* Not found */
}
-__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS];
-__u32 cpu_caps_set[NCAPINTS + NBUGINTS];
+/* Aligned to unsigned long to avoid split lock in atomic bitmap ops */
+__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long));
+__u32 cpu_caps_set[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long));
void load_percpu_segment(int cpu)
{
@@ -1016,13 +1015,14 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#endif
}
-#define NO_SPECULATION BIT(0)
-#define NO_MELTDOWN BIT(1)
-#define NO_SSB BIT(2)
-#define NO_L1TF BIT(3)
-#define NO_MDS BIT(4)
-#define MSBDS_ONLY BIT(5)
-#define NO_SWAPGS BIT(6)
+#define NO_SPECULATION BIT(0)
+#define NO_MELTDOWN BIT(1)
+#define NO_SSB BIT(2)
+#define NO_L1TF BIT(3)
+#define NO_MDS BIT(4)
+#define MSBDS_ONLY BIT(5)
+#define NO_SWAPGS BIT(6)
+#define NO_ITLB_MULTIHIT BIT(7)
#define VULNWL(_vendor, _family, _model, _whitelist) \
{ X86_VENDOR_##_vendor, _family, _model, X86_FEATURE_ANY, _whitelist }
@@ -1043,27 +1043,27 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL(NSC, 5, X86_MODEL_ANY, NO_SPECULATION),
/* Intel Family 6 */
- VULNWL_INTEL(ATOM_SALTWELL, NO_SPECULATION),
- VULNWL_INTEL(ATOM_SALTWELL_TABLET, NO_SPECULATION),
- VULNWL_INTEL(ATOM_SALTWELL_MID, NO_SPECULATION),
- VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION),
- VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION),
-
- VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(ATOM_SILVERMONT_D, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
+ VULNWL_INTEL(ATOM_SALTWELL, NO_SPECULATION | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_SALTWELL_TABLET, NO_SPECULATION | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_SALTWELL_MID, NO_SPECULATION | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION | NO_ITLB_MULTIHIT),
+
+ VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_SILVERMONT_D, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
VULNWL_INTEL(CORE_YONAH, NO_SSB),
- VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
- VULNWL_INTEL(ATOM_AIRMONT_NP, NO_L1TF | NO_SWAPGS),
+ VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_AIRMONT_NP, NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
- VULNWL_INTEL(ATOM_GOLDMONT, NO_MDS | NO_L1TF | NO_SWAPGS),
- VULNWL_INTEL(ATOM_GOLDMONT_D, NO_MDS | NO_L1TF | NO_SWAPGS),
- VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_MDS | NO_L1TF | NO_SWAPGS),
+ VULNWL_INTEL(ATOM_GOLDMONT, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_GOLDMONT_D, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
/*
* Technically, swapgs isn't serializing on AMD (despite it previously
@@ -1073,15 +1073,17 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
* good enough for our purposes.
*/
+ VULNWL_INTEL(ATOM_TREMONT_D, NO_ITLB_MULTIHIT),
+
/* AMD Family 0xf - 0x12 */
- VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS),
- VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS),
- VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS),
- VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS),
+ VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
/* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */
- VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS),
- VULNWL_HYGON(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS),
+ VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
+ VULNWL_HYGON(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT),
{}
};
@@ -1092,19 +1094,30 @@ static bool __init cpu_matches(unsigned long which)
return m && !!(m->driver_data & which);
}
-static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
+u64 x86_read_arch_cap_msr(void)
{
u64 ia32_cap = 0;
+ if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
+ rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
+
+ return ia32_cap;
+}
+
+static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
+{
+ u64 ia32_cap = x86_read_arch_cap_msr();
+
+ /* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */
+ if (!cpu_matches(NO_ITLB_MULTIHIT) && !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
+ setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT);
+
if (cpu_matches(NO_SPECULATION))
return;
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
- if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
- rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
-
if (!cpu_matches(NO_SSB) && !(ia32_cap & ARCH_CAP_SSB_NO) &&
!cpu_has(c, X86_FEATURE_AMD_SSB_NO))
setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
@@ -1121,6 +1134,21 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
if (!cpu_matches(NO_SWAPGS))
setup_force_cpu_bug(X86_BUG_SWAPGS);
+ /*
+ * When the CPU is not mitigated for TAA (TAA_NO=0) set TAA bug when:
+ * - TSX is supported or
+ * - TSX_CTRL is present
+ *
+ * TSX_CTRL check is needed for cases when TSX could be disabled before
+ * the kernel boot e.g. kexec.
+ * 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) &&
+ (cpu_has(c, X86_FEATURE_RTM) ||
+ (ia32_cap & ARCH_CAP_TSX_CTRL_MSR)))
+ setup_force_cpu_bug(X86_BUG_TAA);
+
if (cpu_matches(NO_MELTDOWN))
return;
@@ -1554,6 +1582,8 @@ void __init identify_boot_cpu(void)
#endif
cpu_detect_tlb(&boot_cpu_data);
setup_cr_pinning();
+
+ tsx_init();
}
void identify_secondary_cpu(struct cpuinfo_x86 *c)
@@ -1749,7 +1779,7 @@ static void wait_for_master_cpu(int cpu)
}
#ifdef CONFIG_X86_64
-static void setup_getcpu(int cpu)
+static inline void setup_getcpu(int cpu)
{
unsigned long cpudata = vdso_encode_cpunode(cpu, early_cpu_to_node(cpu));
struct desc_struct d = { };
@@ -1769,7 +1799,50 @@ static void setup_getcpu(int cpu)
write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_CPUNODE, &d, DESCTYPE_S);
}
+
+static inline void ucode_cpu_init(int cpu)
+{
+ if (cpu)
+ load_ucode_ap();
+}
+
+static inline void tss_setup_ist(struct tss_struct *tss)
+{
+ /* Set up the per-CPU TSS IST stacks */
+ tss->x86_tss.ist[IST_INDEX_DF] = __this_cpu_ist_top_va(DF);
+ tss->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI);
+ tss->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB);
+ tss->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE);
+}
+
+#else /* CONFIG_X86_64 */
+
+static inline void setup_getcpu(int cpu) { }
+
+static inline void ucode_cpu_init(int cpu)
+{
+ show_ucode_info_early();
+}
+
+static inline void tss_setup_ist(struct tss_struct *tss) { }
+
+#endif /* !CONFIG_X86_64 */
+
+static inline void tss_setup_io_bitmap(struct tss_struct *tss)
+{
+ tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET_INVALID;
+
+#ifdef CONFIG_X86_IOPL_IOPERM
+ tss->io_bitmap.prev_max = 0;
+ tss->io_bitmap.prev_sequence = 0;
+ memset(tss->io_bitmap.bitmap, 0xff, sizeof(tss->io_bitmap.bitmap));
+ /*
+ * Invalidate the extra array entry past the end of the all
+ * permission bitmap as required by the hardware.
+ */
+ tss->io_bitmap.mapall[IO_BITMAP_LONGS] = ~0UL;
#endif
+}
/*
* cpu_init() initializes state that is per-CPU. Some data is already
@@ -1777,21 +1850,15 @@ static void setup_getcpu(int cpu)
* and IDT. We reload them nevertheless, this function acts as a
* 'CPU state barrier', nothing should get across.
*/
-#ifdef CONFIG_X86_64
-
void cpu_init(void)
{
+ struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
+ struct task_struct *cur = current;
int cpu = raw_smp_processor_id();
- struct task_struct *me;
- struct tss_struct *t;
- int i;
wait_for_master_cpu(cpu);
- if (cpu)
- load_ucode_ap();
-
- t = &per_cpu(cpu_tss_rw, cpu);
+ ucode_cpu_init(cpu);
#ifdef CONFIG_NUMA
if (this_cpu_read(numa_node) == 0 &&
@@ -1800,63 +1867,47 @@ void cpu_init(void)
#endif
setup_getcpu(cpu);
- me = current;
-
pr_debug("Initializing CPU#%d\n", cpu);
- cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
+ if (IS_ENABLED(CONFIG_X86_64) || cpu_feature_enabled(X86_FEATURE_VME) ||
+ boot_cpu_has(X86_FEATURE_TSC) || boot_cpu_has(X86_FEATURE_DE))
+ cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
/*
* Initialize the per-CPU GDT with the boot GDT,
* and set up the GDT descriptor:
*/
-
switch_to_new_gdt(cpu);
- loadsegment(fs, 0);
-
load_current_idt();
- memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
- syscall_init();
-
- wrmsrl(MSR_FS_BASE, 0);
- wrmsrl(MSR_KERNEL_GS_BASE, 0);
- barrier();
+ if (IS_ENABLED(CONFIG_X86_64)) {
+ loadsegment(fs, 0);
+ memset(cur->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
+ syscall_init();
- x86_configure_nx();
- x2apic_setup();
+ wrmsrl(MSR_FS_BASE, 0);
+ wrmsrl(MSR_KERNEL_GS_BASE, 0);
+ barrier();
- /*
- * set up and load the per-CPU TSS
- */
- if (!t->x86_tss.ist[0]) {
- t->x86_tss.ist[IST_INDEX_DF] = __this_cpu_ist_top_va(DF);
- t->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI);
- t->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB);
- t->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE);
+ x2apic_setup();
}
- t->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
-
- /*
- * <= is required because the CPU will access up to
- * 8 bits beyond the end of the IO permission bitmap.
- */
- for (i = 0; i <= IO_BITMAP_LONGS; i++)
- t->io_bitmap[i] = ~0UL;
-
mmgrab(&init_mm);
- me->active_mm = &init_mm;
- BUG_ON(me->mm);
+ cur->active_mm = &init_mm;
+ BUG_ON(cur->mm);
initialize_tlbstate_and_flush();
- enter_lazy_tlb(&init_mm, me);
+ enter_lazy_tlb(&init_mm, cur);
- /*
- * Initialize the TSS. sp0 points to the entry trampoline stack
- * regardless of what task is running.
- */
+ /* Initialize the TSS. */
+ tss_setup_ist(tss);
+ tss_setup_io_bitmap(tss);
set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
+
load_TR_desc();
+ /*
+ * sp0 points to the entry trampoline stack regardless of what task
+ * is running.
+ */
load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1));
load_mm_ldt(&init_mm);
@@ -1864,6 +1915,8 @@ void cpu_init(void)
clear_all_debug_regs();
dbg_restore_debug_regs();
+ doublefault_init_cpu_tss();
+
fpu__init_cpu();
if (is_uv_system())
@@ -1872,63 +1925,6 @@ void cpu_init(void)
load_fixmap_gdt(cpu);
}
-#else
-
-void cpu_init(void)
-{
- int cpu = smp_processor_id();
- struct task_struct *curr = current;
- struct tss_struct *t = &per_cpu(cpu_tss_rw, cpu);
-
- wait_for_master_cpu(cpu);
-
- show_ucode_info_early();
-
- pr_info("Initializing CPU#%d\n", cpu);
-
- if (cpu_feature_enabled(X86_FEATURE_VME) ||
- boot_cpu_has(X86_FEATURE_TSC) ||
- boot_cpu_has(X86_FEATURE_DE))
- cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
-
- load_current_idt();
- switch_to_new_gdt(cpu);
-
- /*
- * Set up and load the per-CPU TSS and LDT
- */
- mmgrab(&init_mm);
- curr->active_mm = &init_mm;
- BUG_ON(curr->mm);
- initialize_tlbstate_and_flush();
- enter_lazy_tlb(&init_mm, curr);
-
- /*
- * Initialize the TSS. sp0 points to the entry trampoline stack
- * regardless of what task is running.
- */
- set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
- load_TR_desc();
- load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1));
-
- load_mm_ldt(&init_mm);
-
- t->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
-
-#ifdef CONFIG_DOUBLEFAULT
- /* Set up doublefault TSS pointer in the GDT */
- __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
-#endif
-
- clear_all_debug_regs();
- dbg_restore_debug_regs();
-
- fpu__init_cpu();
-
- load_fixmap_gdt(cpu);
-}
-#endif
-
/*
* The microcode loader calls this upon late microcode load to recheck features,
* only when microcode has been updated. Caller holds microcode_mutex and CPU