4.10-stable review patch. If anyone has any objections, please let me know.
------------------ From: Andi Kleen <[email protected]> commit cc66afea58f858ff6da7f79b8a595a67bbb4f9a9 upstream. Since: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") all MCEs are printed even when mcelog is running. Fix the regression to not print to dmesg when mcelog is running as it is a consumer too. Signed-off-by: Andi Kleen <[email protected]> [ Massage commit message. ] Signed-off-by: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: linux-edac <[email protected]> Fixes: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/kernel/cpu/mcheck/mce.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -54,6 +54,8 @@ static DEFINE_MUTEX(mce_chrdev_read_mutex); +static int mce_chrdev_open_count; /* #times opened */ + #define mce_log_get_idx_check(p) \ ({ \ RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \ @@ -601,6 +603,10 @@ static int mce_default_notifier(struct n if (atomic_read(&num_notifiers) > 2) return NOTIFY_DONE; + /* Don't print when mcelog is running */ + if (mce_chrdev_open_count > 0) + return NOTIFY_DONE; + __print_mce(m); return NOTIFY_DONE; @@ -1871,7 +1877,6 @@ void mcheck_cpu_clear(struct cpuinfo_x86 */ static DEFINE_SPINLOCK(mce_chrdev_state_lock); -static int mce_chrdev_open_count; /* #times opened */ static int mce_chrdev_open_exclu; /* already open exclusive? */ static int mce_chrdev_open(struct inode *inode, struct file *file)
