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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-16 14:58:12 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-16 14:58:12 -0800
commit37507717de51a8332a34ee07fd88700be88df5bf (patch)
treed6eb5d00a798a4b1ce40c8c4c8ca74b0d22fe1df /arch/x86
parenta68fb48380bb993306dd62a58cbd946b4348222a (diff)
parenta66734297f78707ce39d756b656bfae861d53f62 (diff)
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 perf updates from Ingo Molnar: "This series tightens up RDPMC permissions: currently even highly sandboxed x86 execution environments (such as seccomp) have permission to execute RDPMC, which may leak various perf events / PMU state such as timing information and other CPU execution details. This 'all is allowed' RDPMC mode is still preserved as the (non-default) /sys/devices/cpu/rdpmc=2 setting. The new default is that RDPMC access is only allowed if a perf event is mmap-ed (which is needed to correctly interpret RDPMC counter values in any case). As a side effect of these changes CR4 handling is cleaned up in the x86 code and a shadow copy of the CR4 value is added. The extra CR4 manipulation adds ~ <50ns to the context switch cost between rdpmc-capable and rdpmc-non-capable mms" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks perf/x86: Only allow rdpmc if a perf_event is mapped perf: Pass the event to arch_perf_update_userpage() perf: Add pmu callbacks to track event mapping and unmapping x86: Add a comment clarifying LDT context switching x86: Store a per-cpu shadow copy of CR4 x86: Clean up cr4 manipulation
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/mmu.h2
-rw-r--r--arch/x86/include/asm/mmu_context.h33
-rw-r--r--arch/x86/include/asm/paravirt.h6
-rw-r--r--arch/x86/include/asm/processor.h33
-rw-r--r--arch/x86/include/asm/special_insns.h6
-rw-r--r--arch/x86/include/asm/tlbflush.h77
-rw-r--r--arch/x86/include/asm/virtext.h5
-rw-r--r--arch/x86/kernel/acpi/sleep.c2
-rw-r--r--arch/x86/kernel/cpu/common.c17
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c3
-rw-r--r--arch/x86/kernel/cpu/mcheck/p5.c3
-rw-r--r--arch/x86/kernel/cpu/mcheck/winchip.c3
-rw-r--r--arch/x86/kernel/cpu/mtrr/cyrix.c6
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c6
-rw-r--r--arch/x86/kernel/cpu/perf_event.c76
-rw-r--r--arch/x86/kernel/cpu/perf_event.h2
-rw-r--r--arch/x86/kernel/head32.c1
-rw-r--r--arch/x86/kernel/head64.c2
-rw-r--r--arch/x86/kernel/i387.c3
-rw-r--r--arch/x86/kernel/process.c5
-rw-r--r--arch/x86/kernel/process_32.c2
-rw-r--r--arch/x86/kernel/process_64.c2
-rw-r--r--arch/x86/kernel/setup.c2
-rw-r--r--arch/x86/kernel/xsave.c3
-rw-r--r--arch/x86/kvm/svm.c2
-rw-r--r--arch/x86/kvm/vmx.c10
-rw-r--r--arch/x86/mm/fault.c2
-rw-r--r--arch/x86/mm/init.c13
-rw-r--r--arch/x86/mm/tlb.c3
-rw-r--r--arch/x86/power/cpu.c11
-rw-r--r--arch/x86/realmode/init.c2
-rw-r--r--arch/x86/xen/enlighten.c4
32 files changed, 231 insertions, 116 deletions
diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h
index 876e74e8eec7..09b9620a73b4 100644
--- a/arch/x86/include/asm/mmu.h
+++ b/arch/x86/include/asm/mmu.h
@@ -19,6 +19,8 @@ typedef struct {
struct mutex lock;
void __user *vdso;
+
+ atomic_t perf_rdpmc_allowed; /* nonzero if rdpmc is allowed */
} mm_context_t;
#ifdef CONFIG_SMP
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 4b75d591eb5e..883f6b933fa4 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -18,6 +18,21 @@ static inline void paravirt_activate_mm(struct mm_struct *prev,
}
#endif /* !CONFIG_PARAVIRT */
+#ifdef CONFIG_PERF_EVENTS
+extern struct static_key rdpmc_always_available;
+
+static inline void load_mm_cr4(struct mm_struct *mm)
+{
+ if (static_key_true(&rdpmc_always_available) ||
+ atomic_read(&mm->context.perf_rdpmc_allowed))
+ cr4_set_bits(X86_CR4_PCE);
+ else
+ cr4_clear_bits(X86_CR4_PCE);
+}
+#else
+static inline void load_mm_cr4(struct mm_struct *mm) {}
+#endif
+
/*
* Used for LDT copy/destruction.
*/
@@ -52,15 +67,20 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
/* Stop flush ipis for the previous mm */
cpumask_clear_cpu(cpu, mm_cpumask(prev));
+ /* Load per-mm CR4 state */
+ load_mm_cr4(next);
+
/*
* Load the LDT, if the LDT is different.
*
- * It's possible leave_mm(prev) has been called. If so,
- * then prev->context.ldt could be out of sync with the
- * LDT descriptor or the LDT register. This can only happen
- * if prev->context.ldt is non-null, since we never free
- * an LDT. But LDTs can't be shared across mms, so
- * prev->context.ldt won't be equal to next->context.ldt.
+ * It's possible that prev->context.ldt doesn't match
+ * the LDT register. This can happen if leave_mm(prev)
+ * was called and then modify_ldt changed
+ * prev->context.ldt but suppressed an IPI to this CPU.
+ * In this case, prev->context.ldt != NULL, because we
+ * never free an LDT while the mm still exists. That
+ * means that next->context.ldt != prev->context.ldt,
+ * because mms never share an LDT.
*/
if (unlikely(prev->context.ldt != next->context.ldt))
load_LDT_nolock(&next->context);
@@ -85,6 +105,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
*/
load_cr3(next->pgd);
trace_tlb_flush(TLB_FLUSH_ON_TASK_SWITCH, TLB_FLUSH_ALL);
+ load_mm_cr4(next);
load_LDT_nolock(&next->context);
}
}
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 32444ae939ca..965c47d254aa 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -80,16 +80,16 @@ static inline void write_cr3(unsigned long x)
PVOP_VCALL1(pv_mmu_ops.write_cr3, x);
}
-static inline unsigned long read_cr4(void)
+static inline unsigned long __read_cr4(void)
{
return PVOP_CALL0(unsigned long, pv_cpu_ops.read_cr4);
}
-static inline unsigned long read_cr4_safe(void)
+static inline unsigned long __read_cr4_safe(void)
{
return PVOP_CALL0(unsigned long, pv_cpu_ops.read_cr4_safe);
}
-static inline void write_cr4(unsigned long x)
+static inline void __write_cr4(unsigned long x)
{
PVOP_VCALL1(pv_cpu_ops.write_cr4, x);
}
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index a092a0cce0b7..ec1c93588cef 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -579,39 +579,6 @@ static inline void load_sp0(struct tss_struct *tss,
#define set_iopl_mask native_set_iopl_mask
#endif /* CONFIG_PARAVIRT */
-/*
- * Save the cr4 feature set we're using (ie
- * Pentium 4MB enable and PPro Global page
- * enable), so that any CPU's that boot up
- * after us can get the correct flags.
- */
-extern unsigned long mmu_cr4_features;
-extern u32 *trampoline_cr4_features;
-
-static inline void set_in_cr4(unsigned long mask)
-{
- unsigned long cr4;
-
- mmu_cr4_features |= mask;
- if (trampoline_cr4_features)
- *trampoline_cr4_features = mmu_cr4_features;
- cr4 = read_cr4();
- cr4 |= mask;
- write_cr4(cr4);
-}
-
-static inline void clear_in_cr4(unsigned long mask)
-{
- unsigned long cr4;
-
- mmu_cr4_features &= ~mask;
- if (trampoline_cr4_features)
- *trampoline_cr4_features = mmu_cr4_features;
- cr4 = read_cr4();
- cr4 &= ~mask;
- write_cr4(cr4);
-}
-
typedef struct {
unsigned long seg;
} mm_segment_t;
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index e820c080a4e9..6a4b00fafb00 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -137,17 +137,17 @@ static inline void write_cr3(unsigned long x)
native_write_cr3(x);
}
-static inline unsigned long read_cr4(void)
+static inline unsigned long __read_cr4(void)
{
return native_read_cr4();
}
-static inline unsigned long read_cr4_safe(void)
+static inline unsigned long __read_cr4_safe(void)
{
return native_read_cr4_safe();
}
-static inline void write_cr4(unsigned long x)
+static inline void __write_cr4(unsigned long x)
{
native_write_cr4(x);
}
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 04905bfc508b..cd791948b286 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -15,6 +15,75 @@
#define __flush_tlb_single(addr) __native_flush_tlb_single(addr)
#endif
+struct tlb_state {
+#ifdef CONFIG_SMP
+ struct mm_struct *active_mm;
+ int state;
+#endif
+
+ /*
+ * Access to this CR4 shadow and to H/W CR4 is protected by
+ * disabling interrupts when modifying either one.
+ */
+ unsigned long cr4;
+};
+DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
+
+/* Initialize cr4 shadow for this CPU. */
+static inline void cr4_init_shadow(void)
+{
+ this_cpu_write(cpu_tlbstate.cr4, __read_cr4());
+}
+
+/* Set in this cpu's CR4. */
+static inline void cr4_set_bits(unsigned long mask)
+{
+ unsigned long cr4;
+
+ cr4 = this_cpu_read(cpu_tlbstate.cr4);
+ if ((cr4 | mask) != cr4) {
+ cr4 |= mask;
+ this_cpu_write(cpu_tlbstate.cr4, cr4);
+ __write_cr4(cr4);
+ }
+}
+
+/* Clear in this cpu's CR4. */
+static inline void cr4_clear_bits(unsigned long mask)
+{
+ unsigned long cr4;
+
+ cr4 = this_cpu_read(cpu_tlbstate.cr4);
+ if ((cr4 & ~mask) != cr4) {
+ cr4 &= ~mask;
+ this_cpu_write(cpu_tlbstate.cr4, cr4);
+ __write_cr4(cr4);
+ }
+}
+
+/* Read the CR4 shadow. */
+static inline unsigned long cr4_read_shadow(void)
+{
+ return this_cpu_read(cpu_tlbstate.cr4);
+}
+
+/*
+ * Save some of cr4 feature set we're using (e.g. Pentium 4MB
+ * enable and PPro Global page enable), so that any CPU's that boot
+ * up after us can get the correct flags. This should only be used
+ * during boot on the boot cpu.
+ */
+extern unsigned long mmu_cr4_features;
+extern u32 *trampoline_cr4_features;
+
+static inline void cr4_set_bits_and_update_boot(unsigned long mask)
+{
+ mmu_cr4_features |= mask;
+ if (trampoline_cr4_features)
+ *trampoline_cr4_features = mmu_cr4_features;
+ cr4_set_bits(mask);
+}
+
static inline void __native_flush_tlb(void)
{
native_write_cr3(native_read_cr3());
@@ -24,7 +93,7 @@ static inline void __native_flush_tlb_global_irq_disabled(void)
{
unsigned long cr4;
- cr4 = native_read_cr4();
+ cr4 = this_cpu_read(cpu_tlbstate.cr4);
/* clear PGE */
native_write_cr4(cr4 & ~X86_CR4_PGE);
/* write old PGE again and flush TLBs */
@@ -184,12 +253,6 @@ void native_flush_tlb_others(const struct cpumask *cpumask,
#define TLBSTATE_OK 1
#define TLBSTATE_LAZY 2
-struct tlb_state {
- struct mm_struct *active_mm;
- int state;
-};
-DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
-
static inline void reset_lazy_tlbstate(void)
{
this_cpu_write(cpu_tlbstate.state, 0);
diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h
index 5da71c27cc59..cce9ee68e335 100644
--- a/arch/x86/include/asm/virtext.h
+++ b/arch/x86/include/asm/virtext.h
@@ -19,6 +19,7 @@
#include <asm/vmx.h>
#include <asm/svm.h>
+#include <asm/tlbflush.h>
/*
* VMX functions:
@@ -40,12 +41,12 @@ static inline int cpu_has_vmx(void)
static inline void cpu_vmxoff(void)
{
asm volatile (ASM_VMX_VMXOFF : : : "cc");
- write_cr4(read_cr4() & ~X86_CR4_VMXE);
+ cr4_clear_bits(X86_CR4_VMXE);
}
static inline int cpu_vmx_enabled(void)
{
- return read_cr4() & X86_CR4_VMXE;
+ return __read_cr4() & X86_CR4_VMXE;
}
/** Disable VMX if it is enabled on the current CPU
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 31368207837c..d1daead5fcdd 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -78,7 +78,7 @@ int x86_acpi_suspend_lowlevel(void)
header->pmode_cr0 = read_cr0();
if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
- header->pmode_cr4 = read_cr4();
+ header->pmode_cr4 = __read_cr4();
header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
}
if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index b15bffcaba6d..b5c8ff5e9dfc 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -19,6 +19,7 @@
#include <asm/archrandom.h>
#include <asm/hypervisor.h>
#include <asm/processor.h>
+#include <asm/tlbflush.h>
#include <asm/debugreg.h>
#include <asm/sections.h>
#include <asm/vsyscall.h>
@@ -278,7 +279,7 @@ __setup("nosmep", setup_disable_smep);
static __always_inline void setup_smep(struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_SMEP))
- set_in_cr4(X86_CR4_SMEP);
+ cr4_set_bits(X86_CR4_SMEP);
}
static __init int setup_disable_smap(char *arg)
@@ -298,9 +299,9 @@ static __always_inline void setup_smap(struct cpuinfo_x86 *c)
if (cpu_has(c, X86_FEATURE_SMAP)) {
#ifdef CONFIG_X86_SMAP
- set_in_cr4(X86_CR4_SMAP);
+ cr4_set_bits(X86_CR4_SMAP);
#else
- clear_in_cr4(X86_CR4_SMAP);
+ cr4_clear_bits(X86_CR4_SMAP);
#endif
}
}
@@ -1295,6 +1296,12 @@ void cpu_init(void)
wait_for_master_cpu(cpu);
/*
+ * Initialize the CR4 shadow before doing anything that could
+ * try to read it.
+ */
+ cr4_init_shadow();
+
+ /*
* Load microcode on this cpu if a valid microcode is available.
* This is early microcode loading procedure.
*/
@@ -1313,7 +1320,7 @@ void cpu_init(void)
pr_debug("Initializing CPU#%d\n", cpu);
- clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_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,
@@ -1394,7 +1401,7 @@ void cpu_init(void)
printk(KERN_INFO "Initializing CPU#%d\n", cpu);
if (cpu_feature_enabled(X86_FEATURE_VME) || cpu_has_tsc || cpu_has_de)
- clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
+ cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
load_current_idt();
switch_to_new_gdt(cpu);
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index cdfed7953963..3be9fa69f875 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -44,6 +44,7 @@
#include <asm/processor.h>
#include <asm/traps.h>
+#include <asm/tlbflush.h>
#include <asm/mce.h>
#include <asm/msr.h>
@@ -1452,7 +1453,7 @@ static void __mcheck_cpu_init_generic(void)
bitmap_fill(all_banks, MAX_NR_BANKS);
machine_check_poll(MCP_UC | m_fl, &all_banks);
- set_in_cr4(X86_CR4_MCE);
+ cr4_set_bits(X86_CR4_MCE);
rdmsrl(MSR_IA32_MCG_CAP, cap);
if (cap & MCG_CTL_P)
diff --git a/arch/x86/kernel/cpu/mcheck/p5.c b/arch/x86/kernel/cpu/mcheck/p5.c
index ec2663a708e4..737b0ad4e61a 100644
--- a/arch/x86/kernel/cpu/mcheck/p5.c
+++ b/arch/x86/kernel/cpu/mcheck/p5.c
@@ -9,6 +9,7 @@
#include <asm/processor.h>
#include <asm/traps.h>
+#include <asm/tlbflush.h>
#include <asm/mce.h>
#include <asm/msr.h>
@@ -65,7 +66,7 @@ void intel_p5_mcheck_init(struct cpuinfo_x86 *c)
"Intel old style machine check architecture supported.\n");
/* Enable MCE: */
- set_in_cr4(X86_CR4_MCE);
+ cr4_set_bits(X86_CR4_MCE);
printk(KERN_INFO
"Intel old style machine check reporting enabled on CPU#%d.\n",
smp_processor_id());
diff --git a/arch/x86/kernel/cpu/mcheck/winchip.c b/arch/x86/kernel/cpu/mcheck/winchip.c
index bd5d46a32210..44f138296fbe 100644
--- a/arch/x86/kernel/cpu/mcheck/winchip.c
+++ b/arch/x86/kernel/cpu/mcheck/winchip.c
@@ -8,6 +8,7 @@
#include <asm/processor.h>
#include <asm/traps.h>
+#include <asm/tlbflush.h>
#include <asm/mce.h>
#include <asm/msr.h>
@@ -36,7 +37,7 @@ void winchip_mcheck_init(struct cpuinfo_x86 *c)
lo &= ~(1<<4); /* Enable MCE */
wrmsr(MSR_IDT_FCR1, lo, hi);
- set_in_cr4(X86_CR4_MCE);
+ cr4_set_bits(X86_CR4_MCE);
printk(KERN_INFO
"Winchip machine check reporting enabled on CPU#0.\n");
diff --git a/arch/x86/kernel/cpu/mtrr/cyrix.c b/arch/x86/kernel/cpu/mtrr/cyrix.c
index 9e451b0876b5..f8c81ba0b465 100644
--- a/arch/x86/kernel/cpu/mtrr/cyrix.c
+++ b/arch/x86/kernel/cpu/mtrr/cyrix.c
@@ -138,8 +138,8 @@ static void prepare_set(void)
/* Save value of CR4 and clear Page Global Enable (bit 7) */
if (cpu_has_pge) {
- cr4 = read_cr4();
- write_cr4(cr4 & ~X86_CR4_PGE);
+ cr4 = __read_cr4();
+ __write_cr4(cr4 & ~X86_CR4_PGE);
}
/*
@@ -171,7 +171,7 @@ static void post_set(void)
/* Restore value of CR4 */
if (cpu_has_pge)
- write_cr4(cr4);
+ __write_cr4(cr4);
}
static void cyrix_set_arr(unsigned int reg, unsigned long base,
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 0e25a1bc5ab5..7d74f7b3c6ba 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -678,8 +678,8 @@ static void prepare_set(void) __acquires(set_atomicity_lock)
/* Save value of CR4 and clear Page Global Enable (bit 7) */
if (cpu_has_pge) {
- cr4 = read_cr4();
- write_cr4(cr4 & ~X86_CR4_PGE);
+ cr4 = __read_cr4();
+ __write_cr4(cr4 & ~X86_CR4_PGE);
}
/* Flush all TLBs via a mov %cr3, %reg; mov %reg, %cr3 */
@@ -708,7 +708,7 @@ static void post_set(void) __releases(set_atomicity_lock)
/* Restore value of CR4 */
if (cpu_has_pge)
- write_cr4(cr4);
+ __write_cr4(cr4);
raw_spin_unlock(&set_atomicity_lock);
}
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 143e5f5dc855..b71a7f86d68a 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -31,6 +31,8 @@
#include <asm/nmi.h>
#include <asm/smp.h>
#include <asm/alternative.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
#include <asm/timer.h>
#include <asm/desc.h>
#include <asm/ldt.h>
@@ -43,6 +45,8 @@ DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
.enabled = 1,
};
+struct static_key rdpmc_always_available = STATIC_KEY_INIT_FALSE;
+
u64 __read_mostly hw_cache_event_ids
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
@@ -1327,8 +1331,6 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
break;
case CPU_STARTING:
- if (x86_pmu.attr_rdpmc)
- set_in_cr4(X86_CR4_PCE);
if (x86_pmu.cpu_starting)
x86_pmu.cpu_starting(cpu);
break;
@@ -1804,14 +1806,44 @@ static int x86_pmu_event_init(struct perf_event *event)
event->destroy(event);
}
+ if (ACCESS_ONCE(x86_pmu.attr_rdpmc))
+ event->hw.flags |= PERF_X86_EVENT_RDPMC_ALLOWED;
+
return err;
}
+static void refresh_pce(void *ignored)
+{
+ if (current->mm)
+ load_mm_cr4(current->mm);
+}
+
+static void x86_pmu_event_mapped(struct perf_event *event)
+{
+ if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED))
+ return;
+
+ if (atomic_inc_return(&current->mm->context.perf_rdpmc_allowed) == 1)
+ on_each_cpu_mask(mm_cpumask(current->mm), refresh_pce, NULL, 1);
+}
+
+static void x86_pmu_event_unmapped(struct perf_event *event)
+{
+ if (!current->mm)
+ return;
+
+ if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED))
+ return;
+
+ if (atomic_dec_and_test(&current->mm->context.perf_rdpmc_allowed))
+ on_each_cpu_mask(mm_cpumask(current->mm), refresh_pce, NULL, 1);
+}
+
static int x86_pmu_event_idx(struct perf_event *event)
{
int idx = event->hw.idx;
- if (!x86_pmu.attr_rdpmc)
+ if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED))
return 0;
if (x86_pmu.num_counters_fixed && idx >= INTEL_PMC_IDX_FIXED) {
@@ -1829,16 +1861,6 @@ static ssize_t get_attr_rdpmc(struct device *cdev,
return snprintf(buf, 40, "%d\n", x86_pmu.attr_rdpmc);
}
-static void change_rdpmc(void *info)
-{
- bool enable = !!(unsigned long)info;
-
- if (enable)
- set_in_cr4(X86_CR4_PCE);
- else
- clear_in_cr4(X86_CR4_PCE);
-}
-
static ssize_t set_attr_rdpmc(struct device *cdev,
struct device_attribute *attr,
const char *buf, size_t count)
@@ -1850,14 +1872,27 @@ static ssize_t set_attr_rdpmc(struct device *cdev,
if (ret)
return ret;
+ if (val > 2)
+ return -EINVAL;
+
if (x86_pmu.attr_rdpmc_broken)
return -ENOTSUPP;
- if (!!val != !!x86_pmu.attr_rdpmc) {
- x86_pmu.attr_rdpmc = !!val;
- on_each_cpu(change_rdpmc, (void *)val, 1);
+ if ((val == 2) != (x86_pmu.attr_rdpmc == 2)) {
+ /*
+ * Changing into or out of always available, aka
+ * perf-event-bypassing mode. This path is extremely slow,
+ * but only root can trigger it, so it's okay.
+ */
+ if (val == 2)
+ static_key_slow_inc(&rdpmc_always_available);
+ else
+ static_key_slow_dec(&rdpmc_always_available);
+ on_each_cpu(refresh_pce, NULL, 1);
}
+ x86_pmu.attr_rdpmc = val;
+
return count;
}
@@ -1900,6 +1935,9 @@ static struct pmu pmu = {
.event_init = x86_pmu_event_init,
+ .event_mapped = x86_pmu_event_mapped,
+ .event_unmapped = x86_pmu_event_unmapped,
+
.add = x86_pmu_add,
.del = x86_pmu_del,
.start = x86_pmu_start,
@@ -1914,13 +1952,15 @@ static struct pmu pmu = {
.flush_branch_stack = x86_pmu_flush_branch_stack,
};
-void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
+void arch_perf_update_userpage(struct perf_event *event,
+ struct perf_event_mmap_page *userpg, u64 now)
{
struct cyc2ns_data *data;
userpg->cap_user_time = 0;
userpg->cap_user_time_zero = 0;
- userpg->cap_user_rdpmc = x86_pmu.attr_rdpmc;
+ userpg->cap_user_rdpmc =
+ !!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED);
userpg->pmc_width = x86_pmu.cntval_bits;
if (!sched_clock_stable())
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index 4e6cdb0ddc70..df525d2be1e8 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -71,6 +71,8 @@ struct event_constraint {
#define PERF_X86_EVENT_COMMITTED 0x8 /* event passed commit_txn */
#define PERF_X86_EVENT_PEBS_LD_HSW 0x10 /* haswell style datala, load */
#define PERF_X86_EVENT_PEBS_NA_HSW 0x20 /* haswell style datala, unknown */
+#define PERF_X86_EVENT_RDPMC_ALLOWED 0x40 /* grant rdpmc permission */
+
struct amd_nb {
int nb_id; /* NorthBridge id */
diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index d6c1b9836995..2911ef3a9f1c 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -31,6 +31,7 @@ static void __init i386_default_early_setup(void)
asmlinkage __visible void __init i386_start_kernel(void)
{
+ cr4_init_shadow();
sanitize_boot_params(&boot_params);
/* Call the subarch specific early setup function */
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index efcddfaf05f9..c4f8d4659070 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -156,6 +156,8 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
(__START_KERNEL & PGDIR_MASK)));
BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
+ cr4_init_shadow();
+
/* Kill off the identity-map trampoline */
reset_early_page_tables();
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 81049ffab2d6..d5651fce0b71 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -13,6 +13,7 @@
#include <asm/sigcontext.h>
#include <asm/processor.h>
#include <asm/math_emu.h>
+#include <asm/tlbflush.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/i387.h>
@@ -193,7 +194,7 @@ void fpu_init(void)
if (cpu_has_xmm)
cr4_mask |= X86_CR4_OSXMMEXCPT;
if (cr4_mask)
- set_in_cr4(cr4_mask);
+ cr4_set_bits(cr4_mask);
cr0 = read_cr0();
cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index e127ddaa2d5a..046e2d620bbe 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -28,6 +28,7 @@
#include <asm/fpu-internal.h>
#include <asm/debugreg.h>
#include <asm/nmi.h>
+#include <asm/tlbflush.h>
/*
* per-CPU TSS segments. Threads are completely 'soft' on Linux,
@@ -141,7 +142,7 @@ void flush_thread(void)
static void hard_disable_TSC(void)
{
- write_cr4(read_cr4() | X86_CR4_TSD);
+ cr4_set_bits(X86_CR4_TSD);
}
void disable_TSC(void)
@@ -158,7 +159,7 @@ void disable_TSC(void)
static void hard_enable_TSC(void)
{
- write_cr4(read_cr4() & ~X86_CR4_TSD);
+ cr4_clear_bits(X86_CR4_TSD);
}
static void enable_TSC(void)
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 8f3ebfe710d0..603c4f99cb5a 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -101,7 +101,7 @@ void __show_regs(struct pt_regs *regs, int all)
cr0 = read_cr0();
cr2 = read_cr2();
cr3 = read_cr3();
- cr4 = read_cr4_safe();
+ cr4 = __read_cr4_safe();
printk(KERN_DEFAULT "CR0: %08lx CR2: %08lx CR3: %08lx CR4: %08lx\n",
cr0, cr2, cr3, cr4);
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 5a2c02913af3..67fcc43577d2 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -93,7 +93,7 @@ void __show_regs(struct pt_regs *regs, int all)
cr0 = read_cr0();
cr2 = read_cr2();
cr3 = read_cr3();
- cr4 = read_cr4();
+ cr4 = __read_cr4();
printk(KERN_DEFAULT "FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
fs, fsindex, gs, gsindex, shadowgs);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 27d200929864..0a2421cca01f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1179,7 +1179,7 @@ void __init setup_arch(char **cmdline_p)
if (boot_cpu_data.cpuid_level >= 0) {
/* A CPU has %cr4 if and only if it has CPUID */
- mmu_cr4_features = read_cr4();
+ mmu_cr4_features = __read_cr4();
if (trampoline_cr4_features)
*trampoline_cr4_features = mmu_cr4_features;
}
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index 0de1fae2bdf0..34f66e58a896 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -12,6 +12,7 @@
#include <asm/i387.h>
#include <asm/fpu-internal.h>
#include <asm/sigframe.h>
+#include <asm/tlbflush.h>
#include <asm/xcr.h>
/*
@@ -453,7 +454,7 @@ static void prepare_fx_sw_frame(void)
*/
static inline void xstate_enable(void)
{
- set_in_cr4(X86_CR4_OSXSAVE);
+ cr4_set_bits(X86_CR4_OSXSAVE);
xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
}
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a17d848c6d42..d319e0c24758 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1583,7 +1583,7 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
static int svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
- unsigned long host_cr4_mce = read_cr4() & X86_CR4_MCE;
+ unsigned long host_cr4_mce = cr4_read_shadow() & X86_CR4_MCE;
unsigned long old_cr4 = to_svm(vcpu)->vmcb->save.cr4;
if (cr4 & X86_CR4_VMXE)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3f73bfad0349..14c1a18d206a 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2871,7 +2871,7 @@ static int hardware_enable(void)
u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
u64 old, test_bits;
- if (read_cr4() & X86_CR4_VMXE)
+ if (cr4_read_shadow() & X86_CR4_VMXE)
return -EBUSY;
INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));
@@ -2898,7 +2898,7 @@ static int hardware_enable(void)
/* enable and lock */
wrmsrl(MSR_IA32_FEATURE_CONTROL, old | test_bits);
}
- write_cr4(read_cr4() | X86_CR4_VMXE); /* FIXME: not cpu hotplug safe */
+ cr4_set_bits(X86_CR4_VMXE);
if (vmm_exclusive) {
kvm_cpu_vmxon(phys_addr);
@@ -2935,7 +2935,7 @@ static void hardware_disable(void)
vmclear_local_loaded_vmcss();
kvm_cpu_vmxoff();
}
- write_cr4(read_cr4() & ~X86_CR4_VMXE);
+ cr4_clear_bits(X86_CR4_VMXE);
}
static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
@@ -4450,7 +4450,7 @@ static void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
vmcs_writel(HOST_CR3, read_cr3()); /* 22.2.3 FIXME: shadow tables */
/* Save the most likely value for this task's CR4 in the VMCS. */
- cr4 = read_cr4();
+ cr4 = cr4_read_shadow();
vmcs_writel(HOST_CR4, cr4); /* 22.2.3, 22.2.5 */
vmx->host_state.vmcs_host_cr4 = cr4;
@@ -8146,7 +8146,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
if (test_bit(VCPU_REGS_RIP, (unsigned long *)&vcpu->arch.regs_dirty))
vmcs_writel(GUEST_RIP, vcpu->arch.regs[VCPU_REGS_RIP]);
- cr4 = read_cr4();
+ cr4 = cr4_read_shadow();
if (unlikely(cr4 != vmx->host_state.vmcs_host_cr4)) {
vmcs_writel(HOST_CR4, cr4);
vmx->host_state.vmcs_host_cr4 = cr4;
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index e3ff27a5b634..ede025fb46f1 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -600,7 +600,7 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code,
printk(nx_warning, from_kuid(&init_user_ns, current_uid()));
if (pte && pte_present(*pte) && pte_exec(*pte) &&
(pgd_flags(*pgd) & _PAGE_USER) &&
- (read_cr4() & X86_CR4_SMEP))
+ (__read_cr4() & X86_CR4_SMEP))
printk(smep_warning, from_kuid(&init_user_ns, current_uid()));
}
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 649da47d3827..553c094b9cd7 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -173,11 +173,11 @@ static void __init probe_page_size_mask(void)
/* Enable PSE if available */
if (cpu_has_pse)
- set_in_cr4(X86_CR4_PSE);
+ cr4_set_bits_and_update_boot(X86_CR4_PSE);
/* Enable PGE if available */
if (cpu_has_pge) {
- set_in_cr4(X86_CR4_PGE);
+ cr4_set_bits_and_update_boot(X86_CR4_PGE);
__supported_pte_mask |= _PAGE_GLOBAL;
}
}
@@ -713,6 +713,15 @@ void __init zone_sizes_init(void)
free_area_init_nodes(max_zone_pfns);
}
+DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = {
+#ifdef CONFIG_SMP
+ .active_mm = &init_mm,
+ .state = 0,
+#endif
+ .cr4 = ~0UL, /* fail hard if we screw up cr4 shadow initialization */
+};
+EXPORT_SYMBOL_GPL(cpu_tlbstate);
+
void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache)
{
/* entry 0 MUST be WB (hardwired to speed up translations) */
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index ee61c36d64f8..3250f2371aea 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -14,9 +14,6 @@
#include <asm/uv/uv.h>
#include <linux/debugfs.h>
-DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate)
- = { &init_mm, 0, };
-
/*
* Smarter SMP flushing macros.
* c/o Linus Torvalds.
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index 6ec7910f59bf..3e32ed5648a0 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -105,11 +105,8 @@ static void __save_processor_state(struct saved_context *ctxt)
ctxt->cr0 = read_cr0();
ctxt->cr2 = read_cr2();
ctxt->cr3 = read_cr3();
-#ifdef CONFIG_X86_32
- ctxt->cr4 = read_cr4_safe();
-#else
-/* CONFIG_X86_64 */
- ctxt->cr4 = read_cr4();
+ ctxt->cr4 = __read_cr4_safe();
+#ifdef CONFIG_X86_64
ctxt->cr8 = read_cr8();
#endif
ctxt->misc_enable_saved = !rdmsrl_safe(MSR_IA32_MISC_ENABLE,
@@ -175,12 +172,12 @@ static void notrace __restore_processor_state(struct saved_context *ctxt)
/* cr4 was introduced in the Pentium CPU */
#ifdef CONFIG_X86_32
if (ctxt->cr4)
- write_cr4(ctxt->cr4);
+ __write_cr4(ctxt->cr4);
#else
/* CONFIG X86_64 */
wrmsrl(MSR_EFER, ctxt->efer);
write_cr8(ctxt->cr8);
- write_cr4(ctxt->cr4);
+ __write_cr4(ctxt->cr4);
#endif
write_cr3(ctxt->cr3);
write_cr2(ctxt->cr2);
diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index bad628a620c4..0b7a63d98440 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c
@@ -81,7 +81,7 @@ void __init setup_real_mode(void)
trampoline_header->start = (u64) secondary_startup_64;
trampoline_cr4_features = &trampoline_header->cr4;
- *trampoline_cr4_features = read_cr4();
+ *trampoline_cr4_features = __read_cr4();
trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd);
trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd;
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 78a881b7fc41..bd8b8459c3d0 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1494,10 +1494,10 @@ static void xen_pvh_set_cr_flags(int cpu)
* set them here. For all, OSFXSR OSXMMEXCPT are set in fpu_init.
*/
if (cpu_has_pse)
- set_in_cr4(X86_CR4_PSE);
+ cr4_set_bits_and_update_boot(X86_CR4_PSE);
if (cpu_has_pge)
- set_in_cr4(X86_CR4_PGE);
+ cr4_set_bits_and_update_boot(X86_CR4_PGE);
}
/*