summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/entry.S
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2005-09-03 15:57:56 -0700
committerLinus Torvalds <torvalds@evo.osdl.org>2005-09-05 00:06:25 -0700
commitae6aa2ea8973e200cb3d0564a64a1b441d233428 (patch)
tree2bd12e22134b4f087c2179af0a304ca6dd9ca585 /arch/s390/kernel/entry.S
parent4c139862b8831261d57de02716b92f82e5fb463b (diff)
[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>
Diffstat (limited to 'arch/s390/kernel/entry.S')
-rw-r--r--arch/s390/kernel/entry.S116
1 files changed, 88 insertions, 28 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 1a271b16cb5..cbe7d6a2d02 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -138,14 +138,14 @@ STACK_SIZE = 1 << STACK_SHIFT
st %r12,__SF_BACKCHAIN(%r15) # clear back chain
.endm
- .macro RESTORE_ALL sync
- mvc __LC_RETURN_PSW(8),SP_PSW(%r15) # move user PSW to lowcore
+ .macro RESTORE_ALL psworg,sync
+ mvc \psworg(8),SP_PSW(%r15) # move user PSW to lowcore
.if !\sync
- ni __LC_RETURN_PSW+1,0xfd # clear wait state bit
+ ni \psworg+1,0xfd # clear wait state bit
.endif
lm %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
STORE_TIMER __LC_EXIT_TIMER
- lpsw __LC_RETURN_PSW # back to caller
+ lpsw \psworg # back to caller
.endm
/*
@@ -235,7 +235,7 @@ sysc_return:
tm __TI_flags+3(%r9),_TIF_WORK_SVC
bnz BASED(sysc_work) # there is work to do (signals etc.)
sysc_leave:
- RESTORE_ALL 1
+ RESTORE_ALL __LC_RETURN_PSW,1
#
# recheck if there is more work to do
@@ -312,8 +312,6 @@ sysc_singlestep:
la %r14,BASED(sysc_return) # load adr. of system return
br %r1 # branch to do_single_step
-__critical_end:
-
#
# call trace before and after sys_call
#
@@ -571,7 +569,8 @@ io_return:
tm __TI_flags+3(%r9),_TIF_WORK_INT
bnz BASED(io_work) # there is work to do (signals etc.)
io_leave:
- RESTORE_ALL 0
+ RESTORE_ALL __LC_RETURN_PSW,0
+io_done:
#ifdef CONFIG_PREEMPT
io_preempt:
@@ -621,7 +620,7 @@ io_work_loop:
#
io_mcck_pending:
l %r1,BASED(.Ls390_handle_mcck)
- l %r14,BASED(io_work_loop)
+ la %r14,BASED(io_work_loop)
br %r1 # TIF bit will be cleared by handler
#
@@ -674,6 +673,8 @@ ext_no_vtime:
basr %r14,%r1
b BASED(io_return)
+__critical_end:
+
/*
* Machine check handler routines
*/
@@ -681,6 +682,7 @@ ext_no_vtime:
.globl mcck_int_handler
mcck_int_handler:
spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
+ mvc __LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
SAVE_ALL_BASE __LC_SAVE_AREA+32
la %r12,__LC_MCK_OLD_PSW
@@ -693,17 +695,8 @@ mcck_int_handler:
mvc __LC_ASYNC_ENTER_TIMER(8),__LC_LAST_UPDATE_TIMER
mvc __LC_SYNC_ENTER_TIMER(8),__LC_LAST_UPDATE_TIMER
mvc __LC_EXIT_TIMER(8),__LC_LAST_UPDATE_TIMER
-0: tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
- bno BASED(mcck_no_vtime) # no -> skip cleanup critical
- tm __LC_MCK_OLD_PSW+1,0x01 # interrupting from user ?
- bz BASED(mcck_no_vtime)
- UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
- UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
- mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
-mcck_no_vtime:
#endif
-0:
- tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
+0: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
bno BASED(mcck_int_main) # no -> skip cleanup critical
tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit
bnz BASED(mcck_int_main) # from user -> load async stack
@@ -720,6 +713,16 @@ mcck_int_main:
be BASED(0f)
l %r15,__LC_PANIC_STACK # load panic stack
0: CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
+ bno BASED(mcck_no_vtime) # no -> skip cleanup critical
+ tm __LC_MCK_OLD_PSW+1,0x01 # interrupting from user ?
+ bz BASED(mcck_no_vtime)
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
+mcck_no_vtime:
+#endif
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Ls390_mcck)
@@ -737,7 +740,7 @@ mcck_int_main:
l %r1,BASED(.Ls390_handle_mcck)
basr %r14,%r1 # call machine check handler
mcck_return:
- RESTORE_ALL 0
+ RESTORE_ALL __LC_RETURN_MCCK_PSW,0
#ifdef CONFIG_SMP
/*
@@ -803,6 +806,10 @@ cleanup_table_sysc_leave:
.long sysc_leave + 0x80000000, sysc_work_loop + 0x80000000
cleanup_table_sysc_work_loop:
.long sysc_work_loop + 0x80000000, sysc_reschedule + 0x80000000
+cleanup_table_io_leave:
+ .long io_leave + 0x80000000, io_done + 0x80000000
+cleanup_table_io_work_loop:
+ .long io_work_loop + 0x80000000, io_mcck_pending + 0x80000000
cleanup_critical:
clc 4(4,%r12),BASED(cleanup_table_system_call)
@@ -825,10 +832,26 @@ cleanup_critical:
clc 4(4,%r12),BASED(cleanup_table_sysc_work_loop+4)
bl BASED(cleanup_sysc_return)
0:
+ clc 4(4,%r12),BASED(cleanup_table_io_leave)
+ bl BASED(0f)
+ clc 4(4,%r12),BASED(cleanup_table_io_leave+4)
+ bl BASED(cleanup_io_leave)
+0:
+ clc 4(4,%r12),BASED(cleanup_table_io_work_loop)
+ bl BASED(0f)
+ clc 4(4,%r12),BASED(cleanup_table_io_work_loop+4)
+ bl BASED(cleanup_io_return)
+0:
br %r14
cleanup_system_call:
mvc __LC_RETURN_PSW(8),0(%r12)
+ c %r12,BASED(.Lmck_old_psw)
+ be BASED(0f)
+ la %r12,__LC_SAVE_AREA+16
+ b BASED(1f)
+0: la %r12,__LC_SAVE_AREA+32
+1:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
bh BASED(0f)
@@ -838,11 +861,13 @@ cleanup_system_call:
#endif
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
bh BASED(0f)
- mvc __LC_SAVE_AREA(16),__LC_SAVE_AREA+16
-0: st %r13,__LC_SAVE_AREA+20
+ mvc __LC_SAVE_AREA(16),0(%r12)
+0: st %r13,4(%r12)
+ st %r12,__LC_SAVE_AREA+48 # argh
SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
- st %r15,__LC_SAVE_AREA+28
+ l %r12,__LC_SAVE_AREA+48 # argh
+ st %r15,12(%r12)
lh %r7,0x8a
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
cleanup_vtime:
@@ -879,17 +904,21 @@ cleanup_sysc_return:
cleanup_sysc_leave:
clc 4(4,%r12),BASED(cleanup_sysc_leave_insn)
- be BASED(0f)
+ be BASED(2f)
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
clc 4(4,%r12),BASED(cleanup_sysc_leave_insn+4)
- be BASED(0f)
+ be BASED(2f)
#endif
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
- mvc __LC_SAVE_AREA+16(16),SP_R12(%r15)
- lm %r0,%r11,SP_R0(%r15)
+ c %r12,BASED(.Lmck_old_psw)
+ bne BASED(0f)
+ mvc __LC_SAVE_AREA+32(16),SP_R12(%r15)
+ b BASED(1f)
+0: mvc __LC_SAVE_AREA+16(16),SP_R12(%r15)
+1: lm %r0,%r11,SP_R0(%r15)
l %r15,SP_R15(%r15)
-0: la %r12,__LC_RETURN_PSW
+2: la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_leave_insn:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
@@ -897,6 +926,36 @@ cleanup_sysc_leave_insn:
#endif
.long sysc_leave + 10 + 0x80000000
+cleanup_io_return:
+ mvc __LC_RETURN_PSW(4),0(%r12)
+ mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_io_work_loop)
+ la %r12,__LC_RETURN_PSW
+ br %r14
+
+cleanup_io_leave:
+ clc 4(4,%r12),BASED(cleanup_io_leave_insn)
+ be BASED(2f)
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
+ clc 4(4,%r12),BASED(cleanup_io_leave_insn+4)
+ be BASED(2f)
+#endif
+ mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
+ c %r12,BASED(.Lmck_old_psw)
+ bne BASED(0f)
+ mvc __LC_SAVE_AREA+32(16),SP_R12(%r15)
+ b BASED(1f)
+0: mvc __LC_SAVE_AREA+16(16),SP_R12(%r15)
+1: lm %r0,%r11,SP_R0(%r15)
+ l %r15,SP_R15(%r15)
+2: la %r12,__LC_RETURN_PSW
+ br %r14
+cleanup_io_leave_insn:
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ .long io_leave + 18 + 0x80000000
+#endif
+ .long io_leave + 14 + 0x80000000
+
/*
* Integer constants
*/
@@ -918,6 +977,7 @@ cleanup_sysc_leave_insn:
.Ls390_mcck: .long s390_do_machine_check
.Ls390_handle_mcck:
.long s390_handle_mcck
+.Lmck_old_psw: .long __LC_MCK_OLD_PSW
.Ldo_IRQ: .long do_IRQ
.Ldo_extint: .long do_extint
.Ldo_signal: .long do_signal