diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-02-28 07:42:01 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-03-01 09:59:27 +0100 |
| commit | d9fcf2a1cbd1ff65d0109b1b400938808007fcd5 (patch) | |
| tree | b992cf1bb19fa3a863fe532119773a9be28e18d5 | |
| parent | e7c95effcd3a7a0c9535c809141ca499fede2c31 (diff) | |
s390: fix in-kernel program checks
A program check inside the kernel takes a slightly different path in
entry.S compare to a normal user fault. A recent change moved the store
of the breaking event address into the path taken for in-kernel program
checks as well, but %r14 has not been setup to point to the correct
location. A wild store is the consequence.
Move the store of the breaking event address to the code path for
user space faults.
Fixes: 34525e1f7e8d ("s390: store breaking event address only for program checks")
Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| -rw-r--r-- | arch/s390/kernel/entry.S | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index dff2152350a7..6a7d737d514c 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -490,7 +490,7 @@ ENTRY(pgm_check_handler) jnz .Lpgm_svcper # -> single stepped svc 1: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) - j 3f + j 4f 2: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER lg %r15,__LC_KERNEL_STACK lgr %r14,%r12 @@ -499,8 +499,8 @@ ENTRY(pgm_check_handler) tm __LC_PGM_ILC+2,0x02 # check for transaction abort jz 3f mvc __THREAD_trap_tdb(256,%r14),0(%r13) -3: la %r11,STACK_FRAME_OVERHEAD(%r15) - stg %r10,__THREAD_last_break(%r14) +3: stg %r10,__THREAD_last_break(%r14) +4: la %r11,STACK_FRAME_OVERHEAD(%r15) stmg %r0,%r7,__PT_R0(%r11) mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC stmg %r8,%r9,__PT_PSW(%r11) @@ -509,14 +509,14 @@ ENTRY(pgm_check_handler) xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) stg %r10,__PT_ARGS(%r11) tm __LC_PGM_ILC+3,0x80 # check for per exception - jz 4f + jz 5f tmhh %r8,0x0001 # kernel per event ? jz .Lpgm_kprobe oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID -4: REENABLE_IRQS +5: REENABLE_IRQS xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) larl %r1,pgm_check_table llgh %r10,__PT_INT_CODE+2(%r11) |