linux/arch/s390/kernel/entry64.S
Christian Borntraeger 9e74a6b898 [S390] kernel: show last breaking-event-address on oops
Newer s390 models have a breaking-event-address-recording register.
Each time an instruction causes a break in the sequential instruction
execution, the address is saved in that hardware register. On a program
interrupt the address is copied to the lowcore address 272-279, which
makes it software accessible.

This patch changes the program check handler and the stack overflow
checker to copy the value into the pt_regs argument.
The oops output is enhanced to show the last known breaking address.
It might give additional information if the stack trace is corrupted.

The feature is only available on 64 bit.

The new oops output looks like:

[---------snip----------]
Modules linked in: vmcp sunrpc qeth_l2 dm_mod qeth ccwgroup
CPU: 2 Not tainted 2.6.24zlive-host #8
Process modprobe (pid: 4788, task: 00000000bf3d8718, ksp: 00000000b2b0b8e0)
Krnl PSW : 0704200180000000 000003e000020028 (vmcp_init+0x28/0xe4 [vmcp])
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
Krnl GPRS: 0000000004000002 000003e000020000 0000000000000000 0000000000000001
           000000000015734c ffffffffffffffff 000003e0000b3b00 0000000000000000
           000003e00007ca30 00000000b5bb5d40 00000000b5bb5800 000003e0000b3b00
           000003e0000a2000 00000000003ecf50 00000000b2b0bd50 00000000b2b0bcb0
Krnl Code: 000003e000020018: c0c000040ff4       larl    %r12,3e0000a2000
           000003e00002001e: e3e0f0000024       stg     %r14,0(%r15)
           000003e000020024: a7f40001           brc     15,3e000020026
          >000003e000020028: e310c0100004       lg      %r1,16(%r12)
           000003e00002002e: c020000413dc       larl    %r2,3e0000a27e6
           000003e000020034: c0a00004aee6       larl    %r10,3e0000b5e00
           000003e00002003a: a7490001           lghi    %r4,1
           000003e00002003e: a75900f0           lghi    %r5,240
Call Trace:
([<000000000014b300>] blocking_notifier_call_chain+0x2c/0x40)
 [<000000000015735c>] sys_init_module+0x19d8/0x1b08
 [<0000000000110afc>] sysc_noemu+0x10/0x16
 [<000002000011cda2>] 0x2000011cda2
Last Breaking-Event-Address:
 [<000003e000020024>] vmcp_init+0x24/0xe4 [vmcp]
[---------snip----------]

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:07 +02:00

1047 lines
29 KiB
ArmAsm

/*
* arch/s390/kernel/entry64.S
* S390 low-level entry points.
*
* Copyright (C) IBM Corp. 1999,2006
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
* Hartmut Penner (hp@de.ibm.com),
* Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
* Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/sys.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/cache.h>
#include <asm/lowcore.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/unistd.h>
#include <asm/page.h>
/*
* Stack layout for the system_call stack entry.
* The first few entries are identical to the user_regs_struct.
*/
SP_PTREGS = STACK_FRAME_OVERHEAD
SP_ARGS = STACK_FRAME_OVERHEAD + __PT_ARGS
SP_PSW = STACK_FRAME_OVERHEAD + __PT_PSW
SP_R0 = STACK_FRAME_OVERHEAD + __PT_GPRS
SP_R1 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8
SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16
SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24
SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32
SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40
SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48
SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 64
SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 72
SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 80
SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 88
SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 96
SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 104
SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 112
SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 120
SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC
SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP
SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE = 1 << STACK_SHIFT
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING)
#define BASED(name) name-system_call(%r13)
#ifdef CONFIG_TRACE_IRQFLAGS
.macro TRACE_IRQS_ON
brasl %r14,trace_hardirqs_on
.endm
.macro TRACE_IRQS_OFF
brasl %r14,trace_hardirqs_off
.endm
.macro TRACE_IRQS_CHECK
tm SP_PSW(%r15),0x03 # irqs enabled?
jz 0f
brasl %r14,trace_hardirqs_on
j 1f
0: brasl %r14,trace_hardirqs_off
1:
.endm
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
#define TRACE_IRQS_CHECK
#endif
#ifdef CONFIG_LOCKDEP
.macro LOCKDEP_SYS_EXIT
tm SP_PSW+1(%r15),0x01 # returning to user ?
jz 0f
brasl %r14,lockdep_sys_exit
0:
.endm
#else
#define LOCKDEP_SYS_EXIT
#endif
.macro STORE_TIMER lc_offset
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
stpt \lc_offset
#endif
.endm
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.macro UPDATE_VTIME lc_from,lc_to,lc_sum
lg %r10,\lc_from
slg %r10,\lc_to
alg %r10,\lc_sum
stg %r10,\lc_sum
.endm
#endif
/*
* Register usage in interrupt handlers:
* R9 - pointer to current task structure
* R13 - pointer to literal pool
* R14 - return register for function calls
* R15 - kernel stack pointer
*/
.macro SAVE_ALL_BASE savearea
stmg %r12,%r15,\savearea
larl %r13,system_call
.endm
.macro SAVE_ALL_SVC psworg,savearea
la %r12,\psworg
lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
.endm
.macro SAVE_ALL_SYNC psworg,savearea
la %r12,\psworg
tm \psworg+1,0x01 # test problem state bit
jz 2f # skip stack setup save
lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
#ifdef CONFIG_CHECK_STACK
j 3f
2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
jz stack_overflow
3:
#endif
2:
.endm
.macro SAVE_ALL_ASYNC psworg,savearea
la %r12,\psworg
tm \psworg+1,0x01 # test problem state bit
jnz 1f # from user -> load kernel stack
clc \psworg+8(8),BASED(.Lcritical_end)
jhe 0f
clc \psworg+8(8),BASED(.Lcritical_start)
jl 0f
brasl %r14,cleanup_critical
tm 1(%r12),0x01 # retest problem state after cleanup
jnz 1f
0: lg %r14,__LC_ASYNC_STACK # are we already on the async. stack ?
slgr %r14,%r15
srag %r14,%r14,STACK_SHIFT
jz 2f
1: lg %r15,__LC_ASYNC_STACK # load async stack
#ifdef CONFIG_CHECK_STACK
j 3f
2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
jz stack_overflow
3:
#endif
2:
.endm
.macro CREATE_STACK_FRAME psworg,savearea
aghi %r15,-SP_SIZE # make room for registers & psw
mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
la %r12,\psworg
stg %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
icm %r12,12,__LC_SVC_ILC
stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
st %r12,SP_ILC(%r15)
mvc SP_R12(32,%r15),\savearea # move %r12-%r15 to stack
la %r12,0
stg %r12,__SF_BACKCHAIN(%r15)
.endm
.macro RESTORE_ALL psworg,sync
mvc \psworg(16),SP_PSW(%r15) # move user PSW to lowcore
.if !\sync
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 \psworg # back to caller
.endm
/*
* Scheduler resume function, called by switch_to
* gpr2 = (task_struct *) prev
* gpr3 = (task_struct *) next
* Returns:
* gpr2 = prev
*/
.globl __switch_to
__switch_to:
tm __THREAD_per+4(%r3),0xe8 # is the new process using per ?
jz __switch_to_noper # if not we're fine
stctg %c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
clc __THREAD_per(24,%r3),__SF_EMPTY(%r15)
je __switch_to_noper # we got away without bashing TLB's
lctlg %c9,%c11,__THREAD_per(%r3) # Nope we didn't
__switch_to_noper:
lg %r4,__THREAD_info(%r2) # get thread_info of prev
tm __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
jz __switch_to_no_mcck
ni __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
lg %r4,__THREAD_info(%r3) # get thread_info of next
oi __TI_flags+7(%r4),_TIF_MCCK_PENDING # set it in next
__switch_to_no_mcck:
stmg %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
stg %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp
lg %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp
lmg %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
stg %r3,__LC_CURRENT # __LC_CURRENT = current task struct
lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
lg %r3,__THREAD_info(%r3) # load thread_info from task struct
stg %r3,__LC_THREAD_INFO
aghi %r3,STACK_SIZE
stg %r3,__LC_KERNEL_STACK # __LC_KERNEL_STACK = new kernel stack
br %r14
__critical_start:
/*
* SVC interrupt handler routine. System calls are synchronous events and
* are executed with interrupts enabled.
*/
.globl system_call
system_call:
STORE_TIMER __LC_SYNC_ENTER_TIMER
sysc_saveall:
SAVE_ALL_BASE __LC_SAVE_AREA
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
sysc_vtime:
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
sysc_stime:
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
sysc_update:
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
#endif
sysc_do_svc:
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
slag %r7,%r7,2 # *4 and test for svc 0
jnz sysc_nr_ok
# svc 0: system call number in %r1
cl %r1,BASED(.Lnr_syscalls)
jnl sysc_nr_ok
lgfr %r7,%r1 # clear high word in r1
slag %r7,%r7,2 # svc 0: system call number in %r1
sysc_nr_ok:
mvc SP_ARGS(8,%r15),SP_R7(%r15)
sysc_do_restart:
larl %r10,sys_call_table
#ifdef CONFIG_COMPAT
tm __TI_flags+5(%r9),(_TIF_31BIT>>16) # running in 31 bit mode ?
jno sysc_noemu
larl %r10,sys_call_table_emu # use 31 bit emulation system calls
sysc_noemu:
#endif
tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
lgf %r8,0(%r7,%r10) # load address of system call routine
jnz sysc_tracesys
basr %r14,%r8 # call sys_xxxx
stg %r2,SP_R2(%r15) # store return value (change R2 on stack)
sysc_return:
tm SP_PSW+1(%r15),0x01 # returning to user ?
jno sysc_restore
tm __TI_flags+7(%r9),_TIF_WORK_SVC
jnz sysc_work # there is work to do (signals etc.)
sysc_restore:
#ifdef CONFIG_TRACE_IRQFLAGS
larl %r1,sysc_restore_trace_psw
lpswe 0(%r1)
sysc_restore_trace:
TRACE_IRQS_CHECK
LOCKDEP_SYS_EXIT
#endif
sysc_leave:
RESTORE_ALL __LC_RETURN_PSW,1
sysc_done:
#ifdef CONFIG_TRACE_IRQFLAGS
.align 8
.globl sysc_restore_trace_psw
sysc_restore_trace_psw:
.quad 0, sysc_restore_trace
#endif
#
# recheck if there is more work to do
#
sysc_work_loop:
tm __TI_flags+7(%r9),_TIF_WORK_SVC
jz sysc_restore # there is no work to do
#
# One of the work bits is on. Find out which one.
#
sysc_work:
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jo sysc_mcck_pending
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo sysc_reschedule
tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
jnz sysc_sigpending
tm __TI_flags+7(%r9),_TIF_RESTART_SVC
jo sysc_restart
tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
jo sysc_singlestep
j sysc_restore
sysc_work_done:
#
# _TIF_NEED_RESCHED is set, call schedule
#
sysc_reschedule:
larl %r14,sysc_work_loop
jg schedule # return point is sysc_return
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
larl %r14,sysc_work_loop
jg s390_handle_mcck # TIF bit will be cleared by handler
#
# _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
#
sysc_sigpending:
ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
la %r2,SP_PTREGS(%r15) # load pt_regs
brasl %r14,do_signal # call do_signal
tm __TI_flags+7(%r9),_TIF_RESTART_SVC
jo sysc_restart
tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
jo sysc_singlestep
j sysc_work_loop
#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
ni __TI_flags+7(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
lg %r7,SP_R2(%r15) # load new svc number
slag %r7,%r7,2 # *4
mvc SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
lmg %r2,%r6,SP_R2(%r15) # load svc arguments
j sysc_do_restart # restart svc
#
# _TIF_SINGLE_STEP is set, call do_single_step
#
sysc_singlestep:
ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
lhi %r0,__LC_PGM_OLD_PSW
sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
la %r2,SP_PTREGS(%r15) # address of register-save area
larl %r14,sysc_return # load adr. of system return
jg do_single_step # branch to do_sigtrap
#
# call syscall_trace before and after system call
# special linkage: %r12 contains the return address for trace_svc
#
sysc_tracesys:
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
srl %r7,2
stg %r7,SP_R2(%r15)
brasl %r14,syscall_trace
lghi %r0,NR_syscalls
clg %r0,SP_R2(%r15)
jnh sysc_tracenogo
lg %r7,SP_R2(%r15) # strace might have changed the
sll %r7,2 # system call
lgf %r8,0(%r7,%r10)
sysc_tracego:
lmg %r3,%r6,SP_R3(%r15)
lg %r2,SP_ORIG_R2(%r15)
basr %r14,%r8 # call sys_xxx
stg %r2,SP_R2(%r15) # store return value
sysc_tracenogo:
tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
jz sysc_return
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,1
larl %r14,sysc_return # return point is sysc_return
jg syscall_trace
#
# a new process exits the kernel with ret_from_fork
#
.globl ret_from_fork
ret_from_fork:
lg %r13,__LC_SVC_NEW_PSW+8
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
jo 0f
stg %r15,SP_R15(%r15) # store stack pointer for new kthread
0: brasl %r14,schedule_tail
TRACE_IRQS_ON
stosm 24(%r15),0x03 # reenable interrupts
j sysc_return
#
# kernel_execve function needs to deal with pt_regs that is not
# at the usual place
#
.globl kernel_execve
kernel_execve:
stmg %r12,%r15,96(%r15)
lgr %r14,%r15
aghi %r15,-SP_SIZE
stg %r14,__SF_BACKCHAIN(%r15)
la %r12,SP_PTREGS(%r15)
xc 0(__PT_SIZE,%r12),0(%r12)
lgr %r5,%r12
brasl %r14,do_execve
ltgfr %r2,%r2
je 0f
aghi %r15,SP_SIZE
lmg %r12,%r15,96(%r15)
br %r14
# execve succeeded.
0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts
lg %r15,__LC_KERNEL_STACK # load ksp
aghi %r15,-SP_SIZE # make room for registers & psw
lg %r13,__LC_SVC_NEW_PSW+8
lg %r9,__LC_THREAD_INFO
mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
brasl %r14,execve_tail
j sysc_return
/*
* Program check handler routine
*/
.globl pgm_check_handler
pgm_check_handler:
/*
* First we need to check for a special case:
* Single stepping an instruction that disables the PER event mask will
* cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
* For a single stepped SVC the program check handler gets control after
* the SVC new PSW has been loaded. But we want to execute the SVC first and
* then handle the PER event. Therefore we update the SVC old PSW to point
* to the pgm_check_handler and branch to the SVC handler after we checked
* if we have to load the kernel stack register.
* For every other possible cause for PER event without the PER mask set
* we just ignore the PER event (FIXME: is there anything we have to do
* for LPSW?).
*/
STORE_TIMER __LC_SYNC_ENTER_TIMER
SAVE_ALL_BASE __LC_SAVE_AREA
tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
jnz pgm_per # got per exception -> special case
SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
jz pgm_no_vtime
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
mvc SP_ARGS(8,%r15),__LC_LAST_BREAK
TRACE_IRQS_OFF
lgf %r3,__LC_PGM_ILC # load program interruption code
lghi %r8,0x7f
ngr %r8,%r3
pgm_do_call:
sll %r8,3
larl %r1,pgm_check_table
lg %r1,0(%r8,%r1) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area
larl %r14,sysc_return
br %r1 # branch to interrupt-handler
#
# handle per exception
#
pgm_per:
tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
jnz pgm_per_std # ok, normal per event from user space
# ok its one of the special cases, now we need to find out which one
clc __LC_PGM_OLD_PSW(16),__LC_SVC_NEW_PSW
je pgm_svcper
# no interesting special case, ignore PER event
lmg %r12,%r15,__LC_SAVE_AREA
lpswe __LC_PGM_OLD_PSW
#
# Normal per exception
#
pgm_per_std:
SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
jz pgm_no_vtime2
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime2:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
TRACE_IRQS_OFF
lg %r1,__TI_task(%r9)
tm SP_PSW+1(%r15),0x01 # kernel per event ?
jz kernel_per
mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
lgf %r3,__LC_PGM_ILC # load program interruption code
lghi %r8,0x7f
ngr %r8,%r3 # clear per-event-bit and ilc
je sysc_return
j pgm_do_call
#
# it was a single stepped SVC that is causing all the trouble
#
pgm_svcper:
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
#endif
llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
lg %r1,__TI_task(%r9)
mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
j sysc_do_svc
#
# per was called from kernel, must be kprobes
#
kernel_per:
lhi %r0,__LC_PGM_OLD_PSW
sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
la %r2,SP_PTREGS(%r15) # address of register-save area
larl %r14,sysc_restore # load adr. of system ret, no work
jg do_single_step # branch to do_single_step
/*
* IO interrupt handler routine
*/
.globl io_int_handler
io_int_handler:
STORE_TIMER __LC_ASYNC_ENTER_TIMER
stck __LC_INT_CLOCK
SAVE_ALL_BASE __LC_SAVE_AREA+32
SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
jz io_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
io_no_vtime:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
brasl %r14,do_IRQ # call standard irq handler
io_return:
tm SP_PSW+1(%r15),0x01 # returning to user ?
#ifdef CONFIG_PREEMPT
jno io_preempt # no -> check for preemptive scheduling
#else
jno io_restore # no-> skip resched & signal
#endif
tm __TI_flags+7(%r9),_TIF_WORK_INT
jnz io_work # there is work to do (signals etc.)
io_restore:
#ifdef CONFIG_TRACE_IRQFLAGS
larl %r1,io_restore_trace_psw
lpswe 0(%r1)
io_restore_trace:
TRACE_IRQS_CHECK
LOCKDEP_SYS_EXIT
#endif
io_leave:
RESTORE_ALL __LC_RETURN_PSW,0
io_done:
#ifdef CONFIG_TRACE_IRQFLAGS
.align 8
.globl io_restore_trace_psw
io_restore_trace_psw:
.quad 0, io_restore_trace
#endif
#ifdef CONFIG_PREEMPT
io_preempt:
icm %r0,15,__TI_precount(%r9)
jnz io_restore
# switch to kernel stack
lg %r1,SP_R15(%r15)
aghi %r1,-SP_SIZE
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lgr %r15,%r1
io_resume_loop:
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jno io_restore
larl %r14,io_resume_loop
jg preempt_schedule_irq
#endif
#
# switch to kernel stack, then check TIF bits
#
io_work:
lg %r1,__LC_KERNEL_STACK
aghi %r1,-SP_SIZE
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lgr %r15,%r1
#
# One of the work bits is on. Find out which one.
# Checked are: _TIF_SIGPENDING, _TIF_RESTORE_SIGPENDING, _TIF_NEED_RESCHED
# and _TIF_MCCK_PENDING
#
io_work_loop:
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jo io_mcck_pending
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo io_reschedule
tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
jnz io_sigpending
j io_restore
io_work_done:
#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
j io_work_loop
#
# _TIF_NEED_RESCHED is set, call schedule
#
io_reschedule:
TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
brasl %r14,schedule # call scheduler
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
tm __TI_flags+7(%r9),_TIF_WORK_INT
jz io_restore # there is no work to do
j io_work_loop
#
# _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
#
io_sigpending:
TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
la %r2,SP_PTREGS(%r15) # load pt_regs
brasl %r14,do_signal # call do_signal
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
j io_work_loop
/*
* External interrupt handler routine
*/
.globl ext_int_handler
ext_int_handler:
STORE_TIMER __LC_ASYNC_ENTER_TIMER
stck __LC_INT_CLOCK
SAVE_ALL_BASE __LC_SAVE_AREA+32
SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
jz ext_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
ext_no_vtime:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
llgh %r3,__LC_EXT_INT_CODE # get interruption code
brasl %r14,do_extint
j io_return
__critical_end:
/*
* Machine check handler routines
*/
.globl mcck_int_handler
mcck_int_handler:
la %r1,4095 # revalidate r1
spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
SAVE_ALL_BASE __LC_SAVE_AREA+64
la %r12,__LC_MCK_OLD_PSW
tm __LC_MCCK_CODE,0x80 # system damage?
jo mcck_int_main # yes -> rest of mcck code invalid
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
la %r14,4095
mvc __LC_SAVE_AREA+104(8),__LC_ASYNC_ENTER_TIMER
mvc __LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA-4095(%r14)
tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
jo 1f
la %r14,__LC_SYNC_ENTER_TIMER
clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
jl 0f
la %r14,__LC_ASYNC_ENTER_TIMER
0: clc 0(8,%r14),__LC_EXIT_TIMER
jl 0f
la %r14,__LC_EXIT_TIMER
0: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
jl 0f
la %r14,__LC_LAST_UPDATE_TIMER
0: spt 0(%r14)
mvc __LC_ASYNC_ENTER_TIMER(8),0(%r14)
1:
#endif
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
clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_end)
jhe mcck_int_main
clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_start)
jl mcck_int_main
brasl %r14,cleanup_critical
mcck_int_main:
lg %r14,__LC_PANIC_STACK # are we already on the panic stack?
slgr %r14,%r15
srag %r14,%r14,PAGE_SHIFT
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 SP_PSW+1(%r15),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
tm SP_PSW+1(%r15),0x01 # returning to user ?
jno mcck_return
lg %r1,__LC_KERNEL_STACK # switch to kernel stack
aghi %r1,-SP_SIZE
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lgr %r15,%r1
stosm __SF_EMPTY(%r15),0x04 # turn dat on
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jno mcck_return
TRACE_IRQS_OFF
brasl %r14,s390_handle_mcck
TRACE_IRQS_ON
mcck_return:
mvc __LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
mvc __LC_ASYNC_ENTER_TIMER(8),__LC_SAVE_AREA+104
tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
jno 0f
stpt __LC_EXIT_TIMER
0:
#endif
lpswe __LC_RETURN_MCCK_PSW # back to caller
/*
* Restart interruption handler, kick starter for additional CPUs
*/
#ifdef CONFIG_SMP
__CPUINIT
.globl restart_int_handler
restart_int_handler:
lg %r15,__LC_SAVE_AREA+120 # load ksp
lghi %r10,__LC_CREGS_SAVE_AREA
lctlg %c0,%c15,0(%r10) # get new ctl regs
lghi %r10,__LC_AREGS_SAVE_AREA
lam %a0,%a15,0(%r10)
lmg %r6,%r15,__SF_GPRS(%r15) # load registers from clone
stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
jg start_secondary
.previous
#else
/*
* If we do not run with SMP enabled, let the new CPU crash ...
*/
.globl restart_int_handler
restart_int_handler:
basr %r1,0
restart_base:
lpswe restart_crash-restart_base(%r1)
.align 8
restart_crash:
.long 0x000a0000,0x00000000,0x00000000,0x00000000
restart_go:
#endif
#ifdef CONFIG_CHECK_STACK
/*
* The synchronous or the asynchronous stack overflowed. We are dead.
* No need to properly save the registers, we are going to panic anyway.
* Setup a pt_regs so that show_trace can provide a good call trace.
*/
stack_overflow:
lg %r15,__LC_PANIC_STACK # change to panic stack
aghi %r15,-SP_SIZE
mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
la %r1,__LC_SAVE_AREA
chi %r12,__LC_SVC_OLD_PSW
je 0f
chi %r12,__LC_PGM_OLD_PSW
je 0f
la %r1,__LC_SAVE_AREA+32
0: mvc SP_R12(32,%r15),0(%r1) # move %r12-%r15 to stack
mvc SP_ARGS(8,%r15),__LC_LAST_BREAK
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # clear back chain
la %r2,SP_PTREGS(%r15) # load pt_regs
jg kernel_stack_overflow
#endif
cleanup_table_system_call:
.quad system_call, sysc_do_svc
cleanup_table_sysc_return:
.quad sysc_return, sysc_leave
cleanup_table_sysc_leave:
.quad sysc_leave, sysc_done
cleanup_table_sysc_work_loop:
.quad sysc_work_loop, sysc_work_done
cleanup_table_io_return:
.quad io_return, io_leave
cleanup_table_io_leave:
.quad io_leave, io_done
cleanup_table_io_work_loop:
.quad io_work_loop, io_work_done
cleanup_critical:
clc 8(8,%r12),BASED(cleanup_table_system_call)
jl 0f
clc 8(8,%r12),BASED(cleanup_table_system_call+8)
jl cleanup_system_call
0:
clc 8(8,%r12),BASED(cleanup_table_sysc_return)
jl 0f
clc 8(8,%r12),BASED(cleanup_table_sysc_return+8)
jl cleanup_sysc_return
0:
clc 8(8,%r12),BASED(cleanup_table_sysc_leave)
jl 0f
clc 8(8,%r12),BASED(cleanup_table_sysc_leave+8)
jl cleanup_sysc_leave
0:
clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop)
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_return)
jl 0f
clc 8(8,%r12),BASED(cleanup_table_io_return+8)
jl cleanup_io_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
mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+16)
jhe cleanup_vtime
#endif
clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn)
jh 0f
mvc __LC_SAVE_AREA(32),0(%r12)
0: stg %r13,8(%r12)
stg %r12,__LC_SAVE_AREA+96 # argh
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
lg %r12,__LC_SAVE_AREA+96 # argh
stg %r15,24(%r12)
llgh %r7,__LC_SVC_INT_CODE
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
cleanup_vtime:
clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
jhe cleanup_stime
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
cleanup_stime:
clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+32)
jh cleanup_update
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
cleanup_update:
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
#endif
mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_system_call+8)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_system_call_insn:
.quad sysc_saveall
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.quad system_call
.quad sysc_vtime
.quad sysc_stime
.quad sysc_update
#endif
cleanup_sysc_return:
mvc __LC_RETURN_PSW(8),0(%r12)
mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_leave:
clc 8(8,%r12),BASED(cleanup_sysc_leave_insn)
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 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_sysc_leave_insn:
.quad sysc_done - 4
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.quad sysc_done - 8
#endif
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:
.quad io_done - 4
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.quad io_done - 8
#endif
/*
* Integer constants
*/
.align 4
.Lconst:
.Lnr_syscalls: .long NR_syscalls
.L0x0130: .short 0x130
.L0x0140: .short 0x140
.L0x0150: .short 0x150
.L0x0160: .short 0x160
.L0x0170: .short 0x170
.Lcritical_start:
.quad __critical_start
.Lcritical_end:
.quad __critical_end
.section .rodata, "a"
#define SYSCALL(esa,esame,emu) .long esame
sys_call_table:
#include "syscalls.S"
#undef SYSCALL
#ifdef CONFIG_COMPAT
#define SYSCALL(esa,esame,emu) .long emu
sys_call_table_emu:
#include "syscalls.S"
#undef SYSCALL
#endif