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>

diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index dd1c24ceda50245978c97e13c5b992db3139f329..3f51cf4e8f020e1b972eaa15ef4640ebe028e4e3 100644 (file)
--- 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);