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Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c142
1 files changed, 70 insertions, 72 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index bed0cb83fe24..043d93cdcaad 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -21,6 +21,7 @@
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/syscore_ops.h>
+#include <linux/pgtable.h>
#include <asm/stackprotector.h>
#include <asm/perf_event.h>
@@ -35,7 +36,6 @@
#include <asm/vsyscall.h>
#include <linux/topology.h>
#include <linux/cpumask.h>
-#include <asm/pgtable.h>
#include <linux/atomic.h>
#include <asm/proto.h>
#include <asm/setup.h>
@@ -387,7 +387,30 @@ set_register:
bits_missing);
}
}
-EXPORT_SYMBOL(native_write_cr4);
+#if IS_MODULE(CONFIG_LKDTM)
+EXPORT_SYMBOL_GPL(native_write_cr4);
+#endif
+
+void cr4_update_irqsoff(unsigned long set, unsigned long clear)
+{
+ unsigned long newval, cr4 = this_cpu_read(cpu_tlbstate.cr4);
+
+ lockdep_assert_irqs_disabled();
+
+ newval = (cr4 & ~clear) | set;
+ if (newval != cr4) {
+ this_cpu_write(cpu_tlbstate.cr4, newval);
+ __write_cr4(newval);
+ }
+}
+EXPORT_SYMBOL(cr4_update_irqsoff);
+
+/* Read the CR4 shadow. */
+unsigned long cr4_read_shadow(void)
+{
+ return this_cpu_read(cpu_tlbstate.cr4);
+}
+EXPORT_SYMBOL_GPL(cr4_read_shadow);
void cr4_init(void)
{
@@ -854,30 +877,6 @@ static void init_speculation_control(struct cpuinfo_x86 *c)
}
}
-static void init_cqm(struct cpuinfo_x86 *c)
-{
- if (!cpu_has(c, X86_FEATURE_CQM_LLC)) {
- c->x86_cache_max_rmid = -1;
- c->x86_cache_occ_scale = -1;
- return;
- }
-
- /* will be overridden if occupancy monitoring exists */
- c->x86_cache_max_rmid = cpuid_ebx(0xf);
-
- if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC) ||
- cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL) ||
- cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)) {
- u32 eax, ebx, ecx, edx;
-
- /* QoS sub-leaf, EAX=0Fh, ECX=1 */
- cpuid_count(0xf, 1, &eax, &ebx, &ecx, &edx);
-
- c->x86_cache_max_rmid = ecx;
- c->x86_cache_occ_scale = ebx;
- }
-}
-
void get_cpu_cap(struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;
@@ -945,7 +944,6 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
init_scattered_cpuid_features(c);
init_speculation_control(c);
- init_cqm(c);
/*
* Clear/Set all flags overridden by options, after probe.
@@ -1075,9 +1073,30 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
{}
};
-static bool __init cpu_matches(unsigned long which)
+#define VULNBL_INTEL_STEPPINGS(model, steppings, issues) \
+ X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(INTEL, 6, \
+ INTEL_FAM6_##model, steppings, \
+ X86_FEATURE_ANY, issues)
+
+#define SRBDS BIT(0)
+
+static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
+ VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(HASWELL, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(HASWELL_L, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(HASWELL_G, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(BROADWELL_G, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(BROADWELL, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPING_ANY, SRBDS),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPINGS(0x0, 0xC), SRBDS),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPINGS(0x0, 0xD), SRBDS),
+ {}
+};
+
+static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long which)
{
- const struct x86_cpu_id *m = x86_match_cpu(cpu_vuln_whitelist);
+ const struct x86_cpu_id *m = x86_match_cpu(table);
return m && !!(m->driver_data & which);
}
@@ -1097,31 +1116,34 @@ 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))
+ if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) &&
+ !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT);
- if (cpu_matches(NO_SPECULATION))
+ if (cpu_matches(cpu_vuln_whitelist, NO_SPECULATION))
return;
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
- if (!cpu_matches(NO_SPECTRE_V2))
+ if (!cpu_matches(cpu_vuln_whitelist, NO_SPECTRE_V2))
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
- if (!cpu_matches(NO_SSB) && !(ia32_cap & ARCH_CAP_SSB_NO) &&
+ if (!cpu_matches(cpu_vuln_whitelist, 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);
if (ia32_cap & ARCH_CAP_IBRS_ALL)
setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
- if (!cpu_matches(NO_MDS) && !(ia32_cap & ARCH_CAP_MDS_NO)) {
+ if (!cpu_matches(cpu_vuln_whitelist, NO_MDS) &&
+ !(ia32_cap & ARCH_CAP_MDS_NO)) {
setup_force_cpu_bug(X86_BUG_MDS);
- if (cpu_matches(MSBDS_ONLY))
+ if (cpu_matches(cpu_vuln_whitelist, MSBDS_ONLY))
setup_force_cpu_bug(X86_BUG_MSBDS_ONLY);
}
- if (!cpu_matches(NO_SWAPGS))
+ if (!cpu_matches(cpu_vuln_whitelist, NO_SWAPGS))
setup_force_cpu_bug(X86_BUG_SWAPGS);
/*
@@ -1139,7 +1161,16 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
(ia32_cap & ARCH_CAP_TSX_CTRL_MSR)))
setup_force_cpu_bug(X86_BUG_TAA);
- if (cpu_matches(NO_MELTDOWN))
+ /*
+ * SRBDS affects CPUs which support RDRAND or RDSEED and are listed
+ * in the vulnerability blacklist.
+ */
+ if ((cpu_has(c, X86_FEATURE_RDRAND) ||
+ cpu_has(c, X86_FEATURE_RDSEED)) &&
+ cpu_matches(cpu_vuln_blacklist, SRBDS))
+ setup_force_cpu_bug(X86_BUG_SRBDS);
+
+ if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
return;
/* Rogue Data Cache Load? No! */
@@ -1148,7 +1179,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
- if (cpu_matches(NO_L1TF))
+ if (cpu_matches(cpu_vuln_whitelist, NO_L1TF))
return;
setup_force_cpu_bug(X86_BUG_L1TF);
@@ -1377,20 +1408,6 @@ static void generic_identify(struct cpuinfo_x86 *c)
#endif
}
-static void x86_init_cache_qos(struct cpuinfo_x86 *c)
-{
- /*
- * The heavy lifting of max_rmid and cache_occ_scale are handled
- * in get_cpu_cap(). Here we just set the max_rmid for the boot_cpu
- * in case CQM bits really aren't there in this CPU.
- */
- if (c != &boot_cpu_data) {
- boot_cpu_data.x86_cache_max_rmid =
- min(boot_cpu_data.x86_cache_max_rmid,
- c->x86_cache_max_rmid);
- }
-}
-
/*
* Validate that ACPI/mptables have the same information about the
* effective APIC id and update the package map.
@@ -1503,7 +1520,6 @@ static void identify_cpu(struct cpuinfo_x86 *c)
#endif
x86_init_rdrand(c);
- x86_init_cache_qos(c);
setup_pku(c);
/*
@@ -1591,6 +1607,7 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c)
mtrr_ap_init();
validate_apic_and_package_id(c);
x86_spec_ctrl_setup_ap();
+ update_srbds_msr();
}
static __init int setup_noclflush(char *arg)
@@ -1689,25 +1706,6 @@ void syscall_init(void)
X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT);
}
-DEFINE_PER_CPU(int, debug_stack_usage);
-DEFINE_PER_CPU(u32, debug_idt_ctr);
-
-void debug_stack_set_zero(void)
-{
- this_cpu_inc(debug_idt_ctr);
- load_current_idt();
-}
-NOKPROBE_SYMBOL(debug_stack_set_zero);
-
-void debug_stack_reset(void)
-{
- if (WARN_ON(!this_cpu_read(debug_idt_ctr)))
- return;
- if (this_cpu_dec_return(debug_idt_ctr) == 0)
- load_current_idt();
-}
-NOKPROBE_SYMBOL(debug_stack_reset);
-
#else /* CONFIG_X86_64 */
DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;