[PATCH] s390: machine check handler bugs
The new machine check handler still has a few bugs.
1) The system entry time has to be stored in the machine check handler,
2) the machine check return psw may not be stored at the usual place
because it might overwrite the return psw of the interrupted context,
3) the return address for the call to s390_handle_mcck in the i/o interrupt
handler is not correct,
4) the system call cleanup has to take the different save area of the
machine check handler into account,
5) the machine check handler may not call UPDATE_VTIME before
CREATE_STACK_FRAME, and
6) the io leave path needs a critical section cleanup to make sure that the
TIF_MCCK_PENDING bit is really checked before switching back to user space.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-s390/lowcore.h b/include/asm-s390/lowcore.h
index afe6a9f..c6f51c9 100644
--- a/include/asm-s390/lowcore.h
+++ b/include/asm-s390/lowcore.h
@@ -68,6 +68,7 @@
#define __LC_SYSTEM_TIMER 0x270
#define __LC_LAST_UPDATE_CLOCK 0x278
#define __LC_STEAL_CLOCK 0x280
+#define __LC_RETURN_MCCK_PSW 0x288
#define __LC_KERNEL_STACK 0xC40
#define __LC_THREAD_INFO 0xC44
#define __LC_ASYNC_STACK 0xC48
@@ -90,6 +91,7 @@
#define __LC_SYSTEM_TIMER 0x278
#define __LC_LAST_UPDATE_CLOCK 0x280
#define __LC_STEAL_CLOCK 0x288
+#define __LC_RETURN_MCCK_PSW 0x290
#define __LC_KERNEL_STACK 0xD40
#define __LC_THREAD_INFO 0xD48
#define __LC_ASYNC_STACK 0xD50
@@ -196,7 +198,8 @@
__u64 system_timer; /* 0x270 */
__u64 last_update_clock; /* 0x278 */
__u64 steal_clock; /* 0x280 */
- __u8 pad8[0xc00-0x288]; /* 0x288 */
+ psw_t return_mcck_psw; /* 0x288 */
+ __u8 pad8[0xc00-0x290]; /* 0x290 */
/* System info area */
__u32 save_area[16]; /* 0xc00 */
@@ -285,7 +288,8 @@
__u64 system_timer; /* 0x278 */
__u64 last_update_clock; /* 0x280 */
__u64 steal_clock; /* 0x288 */
- __u8 pad8[0xc00-0x290]; /* 0x290 */
+ psw_t return_mcck_psw; /* 0x290 */
+ __u8 pad8[0xc00-0x2a0]; /* 0x2a0 */
/* System info area */
__u64 save_area[16]; /* 0xc00 */
__u8 pad9[0xd40-0xc80]; /* 0xc80 */