s390: fix machine check handling

Commit eb7e7d76 "s390: Replace __get_cpu_var uses" broke machine check
handling.

We copy machine check information from per-cpu to a stack variable for
local processing. Next we should zap the per-cpu variable, not the
stack variable.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index dd1c24ceda50..3f51cf4e8f02 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -54,12 +54,8 @@ void s390_handle_mcck(void)
          */
         local_irq_save(flags);
         local_mcck_disable();
-        /*
-         * Ummm... Does this make sense at all? Copying the percpu struct
-         * and then zapping it one statement later?
-         */
-        memcpy(&mcck, this_cpu_ptr(&cpu_mcck), sizeof(mcck));
-        memset(&mcck, 0, sizeof(struct mcck_struct));
+        mcck = *this_cpu_ptr(&cpu_mcck);
+        memset(this_cpu_ptr(&cpu_mcck), 0, sizeof(mcck));
         clear_cpu_flag(CIF_MCCK_PENDING);
         local_mcck_enable();
         local_irq_restore(flags);