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-rw-r--r--arch/x86/kernel/acpi/wakeup_64.S10
-rw-r--r--arch/x86/kernel/alternative.c6
-rw-r--r--arch/x86/kernel/amd_nb.c3
-rw-r--r--arch/x86/kernel/apic/apic.c92
-rw-r--r--arch/x86/kernel/apic/bigsmp_32.c24
-rw-r--r--arch/x86/kernel/apic/io_apic.c8
-rw-r--r--arch/x86/kernel/apic/probe_32.c3
-rw-r--r--arch/x86/kernel/asm-offsets_64.c20
-rw-r--r--arch/x86/kernel/cpu/amd.c92
-rw-r--r--arch/x86/kernel/cpu/bugs.c125
-rw-r--r--arch/x86/kernel/cpu/common.c45
-rw-r--r--arch/x86/kernel/cpu/cpuid-deps.c97
-rw-r--r--arch/x86/kernel/cpu/hygon.c21
-rw-r--r--arch/x86/kernel/cpu/intel.c31
-rw-r--r--arch/x86/kernel/cpu/mce/intel.c2
-rw-r--r--arch/x86/kernel/cpu/mce/severity.c4
-rw-r--r--arch/x86/kernel/cpu/mtrr/cyrix.c1
-rw-r--r--arch/x86/kernel/cpu/umwait.c39
-rw-r--r--arch/x86/kernel/cpu/vmware.c94
-rw-r--r--arch/x86/kernel/crash.c2
-rw-r--r--arch/x86/kernel/dumpstack.c7
-rw-r--r--arch/x86/kernel/head_64.S8
-rw-r--r--arch/x86/kernel/hpet.c12
-rw-r--r--arch/x86/kernel/irq.c10
-rw-r--r--arch/x86/kernel/irq_32.c7
-rw-r--r--arch/x86/kernel/irq_64.c9
-rw-r--r--arch/x86/kernel/kprobes/core.c2
-rw-r--r--arch/x86/kernel/kprobes/opt.c2
-rw-r--r--arch/x86/kernel/kvm.c10
-rw-r--r--arch/x86/kernel/machine_kexec_32.c4
-rw-r--r--arch/x86/kernel/pci-dma.c20
-rw-r--r--arch/x86/kernel/ptrace.c1
-rw-r--r--arch/x86/kernel/quirks.c4
-rw-r--r--arch/x86/kernel/smpboot.c5
-rw-r--r--arch/x86/kernel/stacktrace.c2
-rw-r--r--arch/x86/kernel/sysfb_efi.c46
-rw-r--r--arch/x86/kernel/tsc.c2
-rw-r--r--arch/x86/kernel/tsc_msr.c5
-rw-r--r--arch/x86/kernel/umip.c65
-rw-r--r--arch/x86/kernel/uprobes.c17
40 files changed, 641 insertions, 316 deletions
diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S
index b0715c3ac18d..7f9ade13bbcf 100644
--- a/arch/x86/kernel/acpi/wakeup_64.S
+++ b/arch/x86/kernel/acpi/wakeup_64.S
@@ -18,8 +18,13 @@ ENTRY(wakeup_long64)
movq saved_magic, %rax
movq $0x123456789abcdef0, %rdx
cmpq %rdx, %rax
- jne bogus_64_magic
+ je 2f
+ /* stop here on a saved_magic mismatch */
+ movq $0xbad6d61676963, %rcx
+1:
+ jmp 1b
+2:
movw $__KERNEL_DS, %ax
movw %ax, %ss
movw %ax, %ds
@@ -37,9 +42,6 @@ ENTRY(wakeup_long64)
jmp *%rax
ENDPROC(wakeup_long64)
-bogus_64_magic:
- jmp bogus_64_magic
-
ENTRY(do_suspend_lowlevel)
FRAME_BEGIN
subq $8, %rsp
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index ccd32013c47a..9d3a971ea364 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -713,7 +713,7 @@ void __init alternative_instructions(void)
* Don't stop machine check exceptions while patching.
* MCEs only happen when something got corrupted and in this
* case we must do something about the corruption.
- * Ignoring it is worse than a unlikely patching race.
+ * Ignoring it is worse than an unlikely patching race.
* Also machine checks tend to be broadcast and if one CPU
* goes into machine check the others follow quickly, so we don't
* expect a machine check to cause undue problems during to code
@@ -753,8 +753,8 @@ void __init alternative_instructions(void)
* When you use this code to patch more than one byte of an instruction
* you need to make sure that other CPUs cannot execute this code in parallel.
* Also no thread must be currently preempted in the middle of these
- * instructions. And on the local CPU you need to be protected again NMI or MCE
- * handlers seeing an inconsistent instruction while you patch.
+ * instructions. And on the local CPU you need to be protected against NMI or
+ * MCE handlers seeing an inconsistent instruction while you patch.
*/
void __init_or_module text_poke_early(void *addr, const void *opcode,
size_t len)
diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c
index d63e63b7d1d9..251c795b4eb3 100644
--- a/arch/x86/kernel/amd_nb.c
+++ b/arch/x86/kernel/amd_nb.c
@@ -21,6 +21,7 @@
#define PCI_DEVICE_ID_AMD_17H_DF_F4 0x1464
#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
+#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
/* Protect the PCI config register pairs used for SMN and DF indirect access. */
static DEFINE_MUTEX(smn_mutex);
@@ -50,6 +51,7 @@ const struct pci_device_id amd_nb_misc_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
{}
};
EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
@@ -63,6 +65,7 @@ static const struct pci_device_id amd_nb_link_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
{}
};
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 3a31875bd0a3..9e2dd2b296cd 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -590,21 +590,21 @@ static u32 skx_deadline_rev(void)
static const struct x86_cpu_id deadline_match[] = {
DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_HASWELL_X, hsx_deadline_rev),
DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_X, 0x0b000020),
- DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_BROADWELL_XEON_D, bdx_deadline_rev),
+ DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_BROADWELL_D, bdx_deadline_rev),
DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_SKYLAKE_X, skx_deadline_rev),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_CORE, 0x22),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_ULT, 0x20),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_GT3E, 0x17),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL, 0x22),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_L, 0x20),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_G, 0x17),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_CORE, 0x25),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_GT3E, 0x17),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL, 0x25),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_G, 0x17),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_MOBILE, 0xb2),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_DESKTOP, 0xb2),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_L, 0xb2),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE, 0xb2),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_MOBILE, 0x52),
- DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_DESKTOP, 0x52),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_L, 0x52),
+ DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE, 0x52),
{},
};
@@ -722,7 +722,7 @@ static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
/*
- * Temporary interrupt handler.
+ * Temporary interrupt handler and polled calibration function.
*/
static void __init lapic_cal_handler(struct clock_event_device *dev)
{
@@ -834,6 +834,10 @@ bool __init apic_needs_pit(void)
if (!boot_cpu_has(X86_FEATURE_APIC))
return true;
+ /* Virt guests may lack ARAT, but still have DEADLINE */
+ if (!boot_cpu_has(X86_FEATURE_ARAT))
+ return true;
+
/* Deadline timer is based on TSC so no further PIT action required */
if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
return false;
@@ -851,7 +855,8 @@ bool __init apic_needs_pit(void)
static int __init calibrate_APIC_clock(void)
{
struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
- void (*real_handler)(struct clock_event_device *dev);
+ u64 tsc_perj = 0, tsc_start = 0;
+ unsigned long jif_start;
unsigned long deltaj;
long delta, deltatsc;
int pm_referenced = 0;
@@ -878,28 +883,64 @@ static int __init calibrate_APIC_clock(void)
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
"calibrating APIC timer ...\n");
+ /*
+ * There are platforms w/o global clockevent devices. Instead of
+ * making the calibration conditional on that, use a polling based
+ * approach everywhere.
+ */
local_irq_disable();
- /* Replace the global interrupt handler */
- real_handler = global_clock_event->event_handler;
- global_clock_event->event_handler = lapic_cal_handler;
-
/*
* Setup the APIC counter to maximum. There is no way the lapic
* can underflow in the 100ms detection time frame
*/
__setup_APIC_LVTT(0xffffffff, 0, 0);
- /* Let the interrupts run */
+ /*
+ * Methods to terminate the calibration loop:
+ * 1) Global clockevent if available (jiffies)
+ * 2) TSC if available and frequency is known
+ */
+ jif_start = READ_ONCE(jiffies);
+
+ if (tsc_khz) {
+ tsc_start = rdtsc();
+ tsc_perj = div_u64((u64)tsc_khz * 1000, HZ);
+ }
+
+ /*
+ * Enable interrupts so the tick can fire, if a global
+ * clockevent device is available
+ */
local_irq_enable();
- while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
- cpu_relax();
+ while (lapic_cal_loops <= LAPIC_CAL_LOOPS) {
+ /* Wait for a tick to elapse */
+ while (1) {
+ if (tsc_khz) {
+ u64 tsc_now = rdtsc();
+ if ((tsc_now - tsc_start) >= tsc_perj) {
+ tsc_start += tsc_perj;
+ break;
+ }
+ } else {
+ unsigned long jif_now = READ_ONCE(jiffies);
+
+ if (time_after(jif_now, jif_start)) {
+ jif_start = jif_now;
+ break;
+ }
+ }
+ cpu_relax();
+ }
- local_irq_disable();
+ /* Invoke the calibration routine */
+ local_irq_disable();
+ lapic_cal_handler(NULL);
+ local_irq_enable();
+ }
- /* Restore the real event handler */
- global_clock_event->event_handler = real_handler;
+ local_irq_disable();
/* Build delta t1-t2 as apic timer counts down */
delta = lapic_cal_t1 - lapic_cal_t2;
@@ -943,10 +984,11 @@ static int __init calibrate_APIC_clock(void)
levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
/*
- * PM timer calibration failed or not turned on
- * so lets try APIC timer based calibration
+ * PM timer calibration failed or not turned on so lets try APIC
+ * timer based calibration, if a global clockevent device is
+ * available.
*/
- if (!pm_referenced) {
+ if (!pm_referenced && global_clock_event) {
apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
/*
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index 9703b552f25a..38b5b51d42f6 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -33,32 +33,12 @@ static int bigsmp_early_logical_apicid(int cpu)
return early_per_cpu(x86_cpu_to_apicid, cpu);
}
-static inline unsigned long calculate_ldr(int cpu)
-{
- unsigned long val, id;
-
- val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
- id = per_cpu(x86_bios_cpu_apicid, cpu);
- val |= SET_APIC_LOGICAL_ID(id);
-
- return val;
-}
-
/*
- * Set up the logical destination ID.
- *
- * Intel recommends to set DFR, LDR and TPR before enabling
- * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
- * document number 292116). So here it goes...
+ * bigsmp enables physical destination mode
+ * and doesn't use LDR and DFR
*/
static void bigsmp_init_apic_ldr(void)
{
- unsigned long val;
- int cpu = smp_processor_id();
-
- apic_write(APIC_DFR, APIC_DFR_FLAT);
- val = calculate_ldr(cpu);
- apic_write(APIC_LDR, val);
}
static void bigsmp_setup_apic_routing(void)
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index c7bb6c69f21c..d6af97fd170a 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2438,7 +2438,13 @@ unsigned int arch_dynirq_lower_bound(unsigned int from)
* dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use
* gsi_top if ioapic_dynirq_base hasn't been initialized yet.
*/
- return ioapic_initialized ? ioapic_dynirq_base : gsi_top;
+ if (!ioapic_initialized)
+ return gsi_top;
+ /*
+ * For DT enabled machines ioapic_dynirq_base is irrelevant and not
+ * updated. So simply return @from if ioapic_dynirq_base == 0.
+ */
+ return ioapic_dynirq_base ? : from;
}
#ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 0ac9fd667c99..67b33d67002f 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -147,7 +147,8 @@ void __init default_setup_apic_routing(void)
def_to_bigsmp = 0;
break;
}
- /* If P4 and above fall through */
+ /* P4 and above */
+ /* fall through */
case X86_VENDOR_HYGON:
case X86_VENDOR_AMD:
def_to_bigsmp = 1;
diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c
index 8b54d8e3a561..24d2fde30d00 100644
--- a/arch/x86/kernel/asm-offsets_64.c
+++ b/arch/x86/kernel/asm-offsets_64.c
@@ -6,13 +6,28 @@
#include <asm/ia32.h>
#define __SYSCALL_64(nr, sym, qual) [nr] = 1,
+#define __SYSCALL_X32(nr, sym, qual)
static char syscalls_64[] = {
#include <asm/syscalls_64.h>
};
+#undef __SYSCALL_64
+#undef __SYSCALL_X32
+
+#ifdef CONFIG_X86_X32_ABI
+#define __SYSCALL_64(nr, sym, qual)
+#define __SYSCALL_X32(nr, sym, qual) [nr] = 1,
+static char syscalls_x32[] = {
+#include <asm/syscalls_64.h>
+};
+#undef __SYSCALL_64
+#undef __SYSCALL_X32
+#endif
+
#define __SYSCALL_I386(nr, sym, qual) [nr] = 1,
static char syscalls_ia32[] = {
#include <asm/syscalls_32.h>
};
+#undef __SYSCALL_I386
#if defined(CONFIG_KVM_GUEST) && defined(CONFIG_PARAVIRT_SPINLOCKS)
#include <asm/kvm_para.h>
@@ -79,6 +94,11 @@ int main(void)
DEFINE(__NR_syscall_max, sizeof(syscalls_64) - 1);
DEFINE(NR_syscalls, sizeof(syscalls_64));
+#ifdef CONFIG_X86_X32_ABI
+ DEFINE(__NR_syscall_x32_max, sizeof(syscalls_x32) - 1);
+ DEFINE(X32_NR_syscalls, sizeof(syscalls_x32));
+#endif
+
DEFINE(__NR_syscall_compat_max, sizeof(syscalls_ia32) - 1);
DEFINE(IA32_NR_syscalls, sizeof(syscalls_ia32));
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 8d4e50428b68..90f75e515876 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -8,6 +8,7 @@
#include <linux/sched.h>
#include <linux/sched/clock.h>
#include <linux/random.h>
+#include <linux/topology.h>
#include <asm/processor.h>
#include <asm/apic.h>
#include <asm/cacheinfo.h>
@@ -804,6 +805,64 @@ static void init_amd_ln(struct cpuinfo_x86 *c)
msr_set_bit(MSR_AMD64_DE_CFG, 31);
}
+static bool rdrand_force;
+
+static int __init rdrand_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!strcmp(str, "force"))
+ rdrand_force = true;
+ else
+ return -EINVAL;
+
+ return 0;
+}
+early_param("rdrand", rdrand_cmdline);
+
+static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
+{
+ /*
+ * Saving of the MSR used to hide the RDRAND support during
+ * suspend/resume is done by arch/x86/power/cpu.c, which is
+ * dependent on CONFIG_PM_SLEEP.
+ */
+ if (!IS_ENABLED(CONFIG_PM_SLEEP))
+ return;
+
+ /*
+ * The nordrand option can clear X86_FEATURE_RDRAND, so check for
+ * RDRAND support using the CPUID function directly.
+ */
+ if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
+ return;
+
+ msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
+
+ /*
+ * Verify that the CPUID change has occurred in case the kernel is
+ * running virtualized and the hypervisor doesn't support the MSR.
+ */
+ if (cpuid_ecx(1) & BIT(30)) {
+ pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
+ return;
+ }
+
+ clear_cpu_cap(c, X86_FEATURE_RDRAND);
+ pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
+}
+
+static void init_amd_jg(struct cpuinfo_x86 *c)
+{
+ /*
+ * Some BIOS implementations do not restore proper RDRAND support
+ * across suspend and resume. Check on whether to hide the RDRAND
+ * instruction support via CPUID.
+ */
+ clear_rdrand_cpuid_bit(c);
+}
+
static void init_amd_bd(struct cpuinfo_x86 *c)
{
u64 value;
@@ -818,12 +877,23 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
wrmsrl_safe(MSR_F15H_IC_CFG, value);
}
}
+
+ /*
+ * Some BIOS implementations do not restore proper RDRAND support
+ * across suspend and resume. Check on whether to hide the RDRAND
+ * instruction support via CPUID.
+ */
+ clear_rdrand_cpuid_bit(c);
}
static void init_amd_zn(struct cpuinfo_x86 *c)
{
set_cpu_cap(c, X86_FEATURE_ZEN);
+#ifdef CONFIG_NUMA
+ node_reclaim_distance = 32;
+#endif
+
/*
* Fix erratum 1076: CPB feature bit not being set in CPUID.
* Always set it, except when running under a hypervisor.
@@ -860,6 +930,7 @@ static void init_amd(struct cpuinfo_x86 *c)
case 0x10: init_amd_gh(c); break;
case 0x12: init_amd_ln(c); break;
case 0x15: init_amd_bd(c); break;
+ case 0x16: init_amd_jg(c); break;
case 0x17: init_amd_zn(c); break;
}
@@ -879,12 +950,8 @@ static void init_amd(struct cpuinfo_x86 *c)
init_amd_cacheinfo(c);
if (cpu_has(c, X86_FEATURE_XMM2)) {
- unsigned long long val;
- int ret;
-
/*
- * A serializing LFENCE has less overhead than MFENCE, so
- * use it for execution serialization. On families which
+ * Use LFENCE for execution serialization. On families which
* don't have that MSR, LFENCE is already serializing.
* msr_set_bit() uses the safe accessors, too, even if the MSR
* is not present.
@@ -892,19 +959,8 @@ static void init_amd(struct cpuinfo_x86 *c)
msr_set_bit(MSR_F10H_DECFG,
MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT);
- /*
- * Verify that the MSR write was successful (could be running
- * under a hypervisor) and only then assume that LFENCE is
- * serializing.
- */
- ret = rdmsrl_safe(MSR_F10H_DECFG, &val);
- if (!ret && (val & MSR_F10H_DECFG_LFENCE_SERIALIZE)) {
- /* A serializing LFENCE stops RDTSC speculation */
- set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
- } else {
- /* MFENCE stops RDTSC speculation */
- set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
- }
+ /* A serializing LFENCE stops RDTSC speculation */
+ set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
}
/*
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 6d9636c2ca51..91c2561b905f 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -34,6 +34,7 @@
#include "cpu.h"
+static void __init spectre_v1_select_mitigation(void);
static void __init spectre_v2_select_mitigation(void);
static void __init ssb_select_mitigation(void);
static void __init l1tf_select_mitigation(void);
@@ -98,17 +99,11 @@ void __init check_bugs(void)
if (boot_cpu_has(X86_FEATURE_STIBP))
x86_spec_ctrl_mask |= SPEC_CTRL_STIBP;
- /* Select the proper spectre mitigation before patching alternatives */
+ /* Select the proper CPU mitigations before patching alternatives: */
+ spectre_v1_select_mitigation();
spectre_v2_select_mitigation();
-
- /*
- * Select proper mitigation for any exposure to the Speculative Store
- * Bypass vulnerability.
- */
ssb_select_mitigation();
-
l1tf_select_mitigation();
-
mds_select_mitigation();
arch_smt_update();
@@ -274,6 +269,98 @@ static int __init mds_cmdline(char *str)
early_param("mds", mds_cmdline);
#undef pr_fmt
+#define pr_fmt(fmt) "Spectre V1 : " fmt
+
+enum spectre_v1_mitigation {
+ SPECTRE_V1_MITIGATION_NONE,
+ SPECTRE_V1_MITIGATION_AUTO,
+};
+
+static enum spectre_v1_mitigation spectre_v1_mitigation __ro_after_init =
+ SPECTRE_V1_MITIGATION_AUTO;
+
+static const char * const spectre_v1_strings[] = {
+ [SPECTRE_V1_MITIGATION_NONE] = "Vulnerable: __user pointer sanitization and usercopy barriers only; no swapgs barriers",
+ [SPECTRE_V1_MITIGATION_AUTO] = "Mitigation: usercopy/swapgs barriers and __user pointer sanitization",
+};
+
+/*
+ * Does SMAP provide full mitigation against speculative kernel access to
+ * userspace?
+ */
+static bool smap_works_speculatively(void)
+{
+ if (!boot_cpu_has(X86_FEATURE_SMAP))
+ return false;
+
+ /*
+ * On CPUs which are vulnerable to Meltdown, SMAP does not
+ * prevent speculative access to user data in the L1 cache.
+ * Consider SMAP to be non-functional as a mitigation on these
+ * CPUs.
+ */
+ if (boot_cpu_has(X86_BUG_CPU_MELTDOWN))
+ return false;
+
+ return true;
+}
+
+static void __init spectre_v1_select_mitigation(void)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off()) {
+ spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+ return;
+ }
+
+ if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {
+ /*
+ * With Spectre v1, a user can speculatively control either
+ * path of a conditional swapgs with a user-controlled GS
+ * value. The mitigation is to add lfences to both code paths.
+ *
+ * If FSGSBASE is enabled, the user can put a kernel address in
+ * GS, in which case SMAP provides no protection.
+ *
+ * [ NOTE: Don't check for X86_FEATURE_FSGSBASE until the
+ * FSGSBASE enablement patches have been merged. ]
+ *
+ * If FSGSBASE is disabled, the user can only put a user space
+ * address in GS. That makes an attack harder, but still
+ * possible if there's no SMAP protection.
+ */
+ if (!smap_works_speculatively()) {
+ /*
+ * Mitigation can be provided from SWAPGS itself or
+ * PTI as the CR3 write in the Meltdown mitigation
+ * is serializing.
+ *
+ * If neither is there, mitigate with an LFENCE to
+ * stop speculation through swapgs.
+ */
+ if (boot_cpu_has_bug(X86_BUG_SWAPGS) &&
+ !boot_cpu_has(X86_FEATURE_PTI))
+ setup_force_cpu_cap(X86_FEATURE_FENCE_SWAPGS_USER);
+
+ /*
+ * Enable lfences in the kernel entry (non-swapgs)
+ * paths, to prevent user entry from speculatively
+ * skipping swapgs.
+ */
+ setup_force_cpu_cap(X86_FEATURE_FENCE_SWAPGS_KERNEL);
+ }
+ }
+
+ pr_info("%s\n", spectre_v1_strings[spectre_v1_mitigation]);
+}
+
+static int __init nospectre_v1_cmdline(char *str)
+{
+ spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+ return 0;
+}
+early_param("nospectre_v1", nospectre_v1_cmdline);
+
+#undef pr_fmt
#define pr_fmt(fmt) "Spectre V2 : " fmt
static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
@@ -1097,15 +1184,15 @@ static void override_cache_bits(struct cpuinfo_x86 *c)
case INTEL_FAM6_WESTMERE:
case INTEL_FAM6_SANDYBRIDGE:
case INTEL_FAM6_IVYBRIDGE:
- case INTEL_FAM6_HASWELL_CORE:
- case INTEL_FAM6_HASWELL_ULT:
- case INTEL_FAM6_HASWELL_GT3E:
- case INTEL_FAM6_BROADWELL_CORE:
- case INTEL_FAM6_BROADWELL_GT3E:
- case INTEL_FAM6_SKYLAKE_MOBILE:
- case INTEL_FAM6_SKYLAKE_DESKTOP:
- case INTEL_FAM6_KABYLAKE_MOBILE:
- case INTEL_FAM6_KABYLAKE_DESKTOP:
+ case INTEL_FAM6_HASWELL:
+ case INTEL_FAM6_HASWELL_L:
+ case INTEL_FAM6_HASWELL_G:
+ case INTEL_FAM6_BROADWELL:
+ case INTEL_FAM6_BROADWELL_G:
+ case INTEL_FAM6_SKYLAKE_L:
+ case INTEL_FAM6_SKYLAKE:
+ case INTEL_FAM6_KABYLAKE_L:
+ case INTEL_FAM6_KABYLAKE:
if (c->x86_cache_bits < 44)
c->x86_cache_bits = 44;
break;
@@ -1226,7 +1313,7 @@ static ssize_t l1tf_show_state(char *buf)
static ssize_t mds_show_state(char *buf)
{
- if (!hypervisor_is_type(X86_HYPER_NATIVE)) {
+ if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
return sprintf(buf, "%s; SMT Host state unknown\n",
mds_strings[mds_mitigation]);
}
@@ -1290,7 +1377,7 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
break;
case X86_BUG_SPECTRE_V1:
- return sprintf(buf, "Mitigation: __user pointer sanitization\n");
+ return sprintf(buf, "%s\n", spectre_v1_strings[spectre_v1_mitigation]);
case X86_BUG_SPECTRE_V2:
return sprintf(buf, "%s%s%s%s%s%s\n", spectre_v2_strings[spectre_v2_enabled],
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index e0489d2860d3..9ae7d1bcd4f4 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1022,6 +1022,7 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#define NO_L1TF BIT(3)
#define NO_MDS BIT(4)
#define MSBDS_ONLY BIT(5)
+#define NO_SWAPGS BIT(6)
#define VULNWL(_vendor, _family, _model, _whitelist) \
{ X86_VENDOR_##_vendor, _family, _model, X86_FEATURE_ANY, _whitelist }
@@ -1048,30 +1049,39 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION),
VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION),
- VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY),
- VULNWL_INTEL(ATOM_SILVERMONT_X, NO_SSB | NO_L1TF | MSBDS_ONLY),
- VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF | MSBDS_ONLY),
- VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF | MSBDS_ONLY),
- VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF | MSBDS_ONLY),
- VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS),
+ VULNWL_INTEL(ATO