From ae6aa2ea8973e200cb3d0564a64a1b441d233428 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Sat, 3 Sep 2005 15:57:56 -0700 Subject: [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/kernel/entry.S | 116 ++++++++++++++++++++++++++++++++++----------- arch/s390/kernel/entry64.S | 113 ++++++++++++++++++++++++++++++++----------- 2 files changed, 174 insertions(+), 55 deletions(-) (limited to 'arch') 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) @@ -824,11 +831,27 @@ cleanup_critical: bl BASED(0f) 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 diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index d9f22915008..5db5976ff59 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -131,14 +131,14 @@ _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING) stg %r12,__SF_BACKCHAIN(%r15) .endm - .macro RESTORE_ALL sync - mvc __LC_RETURN_PSW(16),SP_PSW(%r15) # move user PSW to lowcore + .macro RESTORE_ALL psworg,sync + mvc \psworg(16),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 lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user STORE_TIMER __LC_EXIT_TIMER - lpswe __LC_RETURN_PSW # back to caller + lpswe \psworg # back to caller .endm /* @@ -233,7 +233,7 @@ sysc_return: tm __TI_flags+7(%r9),_TIF_WORK_SVC jnz 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 @@ -308,8 +308,6 @@ sysc_singlestep: jg do_single_step # branch to do_sigtrap -__critical_end: - # # call syscall_trace before and after system call # special linkage: %r12 contains the return address for trace_svc @@ -612,7 +610,8 @@ io_return: tm __TI_flags+7(%r9),_TIF_WORK_INT jnz 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: @@ -711,6 +710,8 @@ ext_no_vtime: brasl %r14,do_extint j io_return +__critical_end: + /* * Machine check handler routines */ @@ -718,6 +719,7 @@ ext_no_vtime: mcck_int_handler: la %r1,4095 # revalidate r1 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer + mvc __LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA-4095(%r1) lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs SAVE_ALL_BASE __LC_SAVE_AREA+64 la %r12,__LC_MCK_OLD_PSW @@ -730,17 +732,8 @@ 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? - jno mcck_no_vtime # no -> no timer update - tm __LC_MCK_OLD_PSW+1,0x01 # interrupting from user ? - jz 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? jno mcck_int_main # no -> skip cleanup critical tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit jnz mcck_int_main # from user -> load kernel stack @@ -756,6 +749,16 @@ mcck_int_main: jz 0f lg %r15,__LC_PANIC_STACK # load panic stack 0: CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+64 +#ifdef CONFIG_VIRT_CPU_ACCOUNTING + tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid? + jno mcck_no_vtime # no -> no timer update + tm __LC_MCK_OLD_PSW+1,0x01 # interrupting from user ? + jz 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 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct la %r2,SP_PTREGS(%r15) # load pt_regs brasl %r14,s390_do_machine_check @@ -771,7 +774,7 @@ mcck_int_main: jno mcck_return brasl %r14,s390_handle_mcck mcck_return: - RESTORE_ALL 0 + RESTORE_ALL __LC_RETURN_MCCK_PSW,0 #ifdef CONFIG_SMP /* @@ -833,6 +836,10 @@ cleanup_table_sysc_leave: .quad sysc_leave, sysc_work_loop cleanup_table_sysc_work_loop: .quad sysc_work_loop, sysc_reschedule +cleanup_table_io_leave: + .quad io_leave, io_done +cleanup_table_io_work_loop: + .quad io_work_loop, io_mcck_pending cleanup_critical: clc 8(8,%r12),BASED(cleanup_table_system_call) @@ -854,11 +861,27 @@ cleanup_critical: jl 0f clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop+8) jl cleanup_sysc_return +0: + clc 8(8,%r12),BASED(cleanup_table_io_leave) + jl 0f + clc 8(8,%r12),BASED(cleanup_table_io_leave+8) + jl cleanup_io_leave +0: + clc 8(8,%r12),BASED(cleanup_table_io_work_loop) + jl 0f + clc 8(8,%r12),BASED(cleanup_table_io_work_loop+8) + jl cleanup_io_return 0: br %r14 cleanup_system_call: mvc __LC_RETURN_PSW(16),0(%r12) + cghi %r12,__LC_MCK_OLD_PSW + je 0f + la %r12,__LC_SAVE_AREA+32 + j 1f +0: la %r12,__LC_SAVE_AREA+64 +1: #ifdef CONFIG_VIRT_CPU_ACCOUNTING clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+8) jh 0f @@ -868,11 +891,13 @@ cleanup_system_call: #endif clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn) jh 0f - mvc __LC_SAVE_AREA(32),__LC_SAVE_AREA+32 -0: stg %r13,__LC_SAVE_AREA+40 + mvc __LC_SAVE_AREA(32),0(%r12) +0: stg %r13,8(%r12) + stg %r12,__LC_SAVE_AREA+96 # argh SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA - stg %r15,__LC_SAVE_AREA+56 + lg %r12,__LC_SAVE_AREA+96 # argh + stg %r15,24(%r12) llgh %r7,__LC_SVC_INT_CODE #ifdef CONFIG_VIRT_CPU_ACCOUNTING cleanup_vtime: @@ -909,17 +934,21 @@ cleanup_sysc_return: cleanup_sysc_leave: clc 8(8,%r12),BASED(cleanup_sysc_leave_insn) - je 0f + je 2f #ifdef CONFIG_VIRT_CPU_ACCOUNTING mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER clc 8(8,%r12),BASED(cleanup_sysc_leave_insn+8) - je 0f + je 2f #endif mvc __LC_RETURN_PSW(16),SP_PSW(%r15) - mvc __LC_SAVE_AREA+32(32),SP_R12(%r15) - lmg %r0,%r11,SP_R0(%r15) + cghi %r12,__LC_MCK_OLD_PSW + jne 0f + mvc __LC_SAVE_AREA+64(32),SP_R12(%r15) + j 1f +0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15) +1: lmg %r0,%r11,SP_R0(%r15) lg %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 @@ -927,6 +956,36 @@ cleanup_sysc_leave_insn: #endif .quad sysc_leave + 12 +cleanup_io_return: + mvc __LC_RETURN_PSW(8),0(%r12) + mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_io_work_loop) + la %r12,__LC_RETURN_PSW + br %r14 + +cleanup_io_leave: + clc 8(8,%r12),BASED(cleanup_io_leave_insn) + je 2f +#ifdef CONFIG_VIRT_CPU_ACCOUNTING + mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER + clc 8(8,%r12),BASED(cleanup_io_leave_insn+8) + je 2f +#endif + mvc __LC_RETURN_PSW(16),SP_PSW(%r15) + cghi %r12,__LC_MCK_OLD_PSW + jne 0f + mvc __LC_SAVE_AREA+64(32),SP_R12(%r15) + j 1f +0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15) +1: lmg %r0,%r11,SP_R0(%r15) + lg %r15,SP_R15(%r15) +2: la %r12,__LC_RETURN_PSW + br %r14 +cleanup_io_leave_insn: +#ifdef CONFIG_VIRT_CPU_ACCOUNTING + .quad io_leave + 20 +#endif + .quad io_leave + 16 + /* * Integer constants */ -- cgit v1.2.3