diff options
| author | Chen, Gong <[email protected]> | 2015-08-12 18:29:37 +0200 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-08-13 10:12:51 +0200 |
| commit | f29a7aff4bd60ebc3da4982f80144a4158c4c74a (patch) | |
| tree | 1403d279016fbaba44d00cb98e038b439fc50d65 | |
| parent | fd4cf79fcc4b5130ced8fd8c40378d3cec2e5fa8 (diff) | |
x86/mce: Avoid potential deadlock due to printk() in MCE context
Printing in MCE context is a no-no, currently, as printk() is
not NMI-safe. If some of the notifiers on the MCE chain call do
so, we may deadlock. In order to avoid that, delay printk() to
process context where it is safe.
Reported-by: Xie XiuQi <[email protected]>
Signed-off-by: Chen, Gong <[email protected]>
[ Fold in subsequent patch from Boris for early boot logging. ]
Signed-off-by: Tony Luck <[email protected]>
[ Kick irq_work in mce_log() directly. ]
Signed-off-by: Borislav Petkov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce-apei.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce_intel.c | 1 |
3 files changed, 2 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce-apei.c b/arch/x86/kernel/cpu/mcheck/mce-apei.c index a1aef9533154..34c89a3e8260 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-apei.c +++ b/arch/x86/kernel/cpu/mcheck/mce-apei.c @@ -57,7 +57,6 @@ void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err) m.addr = mem_err->physical_addr; mce_log(&m); - mce_notify_irq(); } EXPORT_SYMBOL_GPL(apei_mce_report_mem_error); diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 82603690b65c..9568bb55bfe2 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -159,7 +159,8 @@ void mce_log(struct mce *mce) /* Emit the trace record: */ trace_mce_record(mce); - atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, mce); + if (!mce_gen_pool_add(mce)) + irq_work_queue(&mce_irq_work); mce->finished = 0; wmb(); @@ -1122,7 +1123,6 @@ void do_machine_check(struct pt_regs *regs, long error_code) /* assuming valid severity level != 0 */ m.severity = severity; m.usable_addr = mce_usable_address(&m); - mce_gen_pool_add(&m); mce_log(&m); diff --git a/arch/x86/kernel/cpu/mcheck/mce_intel.c b/arch/x86/kernel/cpu/mcheck/mce_intel.c index 844f56c5616d..70f567f774ed 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_intel.c +++ b/arch/x86/kernel/cpu/mcheck/mce_intel.c @@ -246,7 +246,6 @@ static void intel_threshold_interrupt(void) return; machine_check_poll(MCP_TIMESTAMP, this_cpu_ptr(&mce_banks_owned)); - mce_notify_irq(); } /* |