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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-19 10:40:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-19 10:40:11 -0700
commit8de3f7a70572c55201f02b9db804e8eef13cb840 (patch)
tree601365917a673d3112e7f970b7a3997aab701aaf
parentb93124202fc10450a923e24cb052cacb40b2aa46 (diff)
parent24223657806a0ebd0ae5c9caaf7b021091889cf2 (diff)
downloadop-kernel-dev-8de3f7a70572c55201f02b9db804e8eef13cb840.zip
op-kernel-dev-8de3f7a70572c55201f02b9db804e8eef13cb840.tar.gz
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar: "Two kernel side fixes: - an Intel uncore PMU driver potential crash fix - a kprobes/perf-call-graph interaction fix" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Use rdmsrl_safe() when initializing RAPL PMU kprobes/x86: Fix page-fault handling logic
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel_rapl.c12
-rw-r--r--arch/x86/kernel/kprobes/core.c16
2 files changed, 16 insertions, 12 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel_rapl.c b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
index 4b9a9e9..7c87424 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
@@ -535,6 +535,7 @@ static int rapl_cpu_prepare(int cpu)
struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
int phys_id = topology_physical_package_id(cpu);
u64 ms;
+ u64 msr_rapl_power_unit_bits;
if (pmu)
return 0;
@@ -542,6 +543,9 @@ static int rapl_cpu_prepare(int cpu)
if (phys_id < 0)
return -1;
+ if (!rdmsrl_safe(MSR_RAPL_POWER_UNIT, &msr_rapl_power_unit_bits))
+ return -1;
+
pmu = kzalloc_node(sizeof(*pmu), GFP_KERNEL, cpu_to_node(cpu));
if (!pmu)
return -1;
@@ -555,8 +559,7 @@ static int rapl_cpu_prepare(int cpu)
*
* we cache in local PMU instance
*/
- rdmsrl(MSR_RAPL_POWER_UNIT, pmu->hw_unit);
- pmu->hw_unit = (pmu->hw_unit >> 8) & 0x1FULL;
+ pmu->hw_unit = (msr_rapl_power_unit_bits >> 8) & 0x1FULL;
pmu->pmu = &rapl_pmu_class;
/*
@@ -677,7 +680,9 @@ static int __init rapl_pmu_init(void)
cpu_notifier_register_begin();
for_each_online_cpu(cpu) {
- rapl_cpu_prepare(cpu);
+ ret = rapl_cpu_prepare(cpu);
+ if (ret)
+ goto out;
rapl_cpu_init(cpu);
}
@@ -700,6 +705,7 @@ static int __init rapl_pmu_init(void)
hweight32(rapl_cntr_mask),
ktime_to_ms(pmu->timer_interval));
+out:
cpu_notifier_register_done();
return 0;
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 79a3f96..61b17dc 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -897,9 +897,10 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
- switch (kcb->kprobe_status) {
- case KPROBE_HIT_SS:
- case KPROBE_REENTER:
+ if (unlikely(regs->ip == (unsigned long)cur->ainsn.insn)) {
+ /* This must happen on single-stepping */
+ WARN_ON(kcb->kprobe_status != KPROBE_HIT_SS &&
+ kcb->kprobe_status != KPROBE_REENTER);
/*
* We are here because the instruction being single
* stepped caused a page fault. We reset the current
@@ -914,9 +915,8 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
else
reset_current_kprobe();
preempt_enable_no_resched();
- break;
- case KPROBE_HIT_ACTIVE:
- case KPROBE_HIT_SSDONE:
+ } else if (kcb->kprobe_status == KPROBE_HIT_ACTIVE ||
+ kcb->kprobe_status == KPROBE_HIT_SSDONE) {
/*
* We increment the nmissed count for accounting,
* we can also use npre/npostfault count for accounting
@@ -945,10 +945,8 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
* fixup routine could not handle it,
* Let do_page_fault() fix it.
*/
- break;
- default:
- break;
}
+
return 0;
}
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