linux/arch/mn10300/kernel/entry.S
Akira Takeuchi 3da06ed736 mn10300: Fix crash just after starting userspace on !CONFIG_PREEMPT
The mn10300 kernel crashes just after starting userspace programs, if
CONFIG_PREEMPT is disabled:

  Freeing unused kernel memory: 96K (90286000 - 9029e000)
  MISALIGN: 97c33ff9: unsupported instruction f
  MISALIGN: 97c33ff9: unsupported instruction f
  MISALIGN: 97c33ff9: unsupported instruction f
  :

This fixes the problem that was introduced by commit d17fc238ac
("MN10300: Enable IRQs more in system call exit work path").

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-10 14:54:59 -07:00

773 lines
19 KiB
ArmAsm

###############################################################################
#
# MN10300 Exception and interrupt entry points
#
# Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
# Modified by David Howells (dhowells@redhat.com)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public Licence
# as published by the Free Software Foundation; either version
# 2 of the Licence, or (at your option) any later version.
#
###############################################################################
#include <linux/sys.h>
#include <linux/linkage.h>
#include <asm/smp.h>
#include <asm/irqflags.h>
#include <asm/thread_info.h>
#include <asm/intctl-regs.h>
#include <asm/busctl-regs.h>
#include <asm/timer-regs.h>
#include <unit/leds.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/errno.h>
#include <asm/asm-offsets.h>
#include <asm/frame.inc>
#if defined(CONFIG_SMP) && defined(CONFIG_GDBSTUB)
#include <asm/gdb-stub.h>
#endif /* CONFIG_SMP && CONFIG_GDBSTUB */
#ifdef CONFIG_PREEMPT
#define preempt_stop LOCAL_IRQ_DISABLE
#else
#define preempt_stop
#define resume_kernel restore_all
#endif
.am33_2
###############################################################################
#
# the return path for a forked child
# - on entry, D0 holds the address of the previous task to run
#
###############################################################################
ENTRY(ret_from_fork)
call schedule_tail[],0
GET_THREAD_INFO a2
# return 0 to indicate child process
clr d0
mov d0,(REG_D0,fp)
jmp syscall_exit
ENTRY(ret_from_kernel_thread)
call schedule_tail[],0
mov (REG_D0,fp),d0
mov (REG_A0,fp),a0
calls (a0)
GET_THREAD_INFO a2 # A2 must be set on return from sys_exit()
clr d0
mov d0,(REG_D0,fp)
jmp syscall_exit
###############################################################################
#
# system call handler
#
###############################################################################
ENTRY(system_call)
add -4,sp
SAVE_ALL
mov d0,(REG_ORIG_D0,fp)
GET_THREAD_INFO a2
cmp nr_syscalls,d0
bcc syscall_badsys
btst _TIF_SYSCALL_TRACE,(TI_flags,a2)
bne syscall_entry_trace
syscall_call:
add d0,d0,a1
add a1,a1
mov (REG_A0,fp),d0
mov (sys_call_table,a1),a0
calls (a0)
mov d0,(REG_D0,fp)
syscall_exit:
# make sure we don't miss an interrupt setting need_resched or
# sigpending between sampling and the rti
LOCAL_IRQ_DISABLE
mov (TI_flags,a2),d2
btst _TIF_ALLWORK_MASK,d2
bne syscall_exit_work
restore_all:
RESTORE_ALL
###############################################################################
#
# perform work that needs to be done immediately before resumption and syscall
# tracing
#
###############################################################################
ALIGN
syscall_exit_work:
mov (REG_EPSW,fp),d0
and EPSW_nSL,d0
beq resume_kernel # returning to supervisor mode
LOCAL_IRQ_ENABLE # could let syscall_trace_exit() call
# schedule() instead
btst _TIF_SYSCALL_TRACE,d2
beq work_pending
mov fp,d0
call syscall_trace_exit[],0 # do_syscall_trace(regs)
jmp resume_userspace
ALIGN
work_pending:
btst _TIF_NEED_RESCHED,d2
beq work_notifysig
work_resched:
call schedule[],0
resume_userspace:
# make sure we don't miss an interrupt setting need_resched or
# sigpending between sampling and the rti
LOCAL_IRQ_DISABLE
# is there any work to be done other than syscall tracing?
mov (TI_flags,a2),d2
btst _TIF_WORK_MASK,d2
beq restore_all
LOCAL_IRQ_ENABLE
btst _TIF_NEED_RESCHED,d2
bne work_resched
# deal with pending signals and notify-resume requests
work_notifysig:
mov fp,d0
mov d2,d1
call do_notify_resume[],0
jmp resume_userspace
# perform syscall entry tracing
syscall_entry_trace:
mov -ENOSYS,d0
mov d0,(REG_D0,fp)
mov fp,d0
call syscall_trace_entry[],0 # returns the syscall number to actually use
mov (REG_D1,fp),d1
cmp nr_syscalls,d0
bcs syscall_call
jmp syscall_exit
syscall_badsys:
mov -ENOSYS,d0
mov d0,(REG_D0,fp)
jmp resume_userspace
# userspace resumption stub bypassing syscall exit tracing
.globl ret_from_exception, ret_from_intr
ALIGN
ret_from_exception:
preempt_stop
ret_from_intr:
GET_THREAD_INFO a2
mov (REG_EPSW,fp),d0 # need to deliver signals before
# returning to userspace
and EPSW_nSL,d0
bne resume_userspace # returning to userspace
#ifdef CONFIG_PREEMPT
resume_kernel:
LOCAL_IRQ_DISABLE
mov (TI_preempt_count,a2),d0 # non-zero preempt_count ?
cmp 0,d0
bne restore_all
need_resched:
btst _TIF_NEED_RESCHED,(TI_flags,a2)
beq restore_all
mov (REG_EPSW,fp),d0
and EPSW_IM,d0
cmp EPSW_IM_7,d0 # interrupts off (exception path) ?
bne restore_all
call preempt_schedule_irq[],0
jmp need_resched
#else
jmp resume_kernel
#endif
###############################################################################
#
# IRQ handler entry point
# - intended to be entered at multiple priorities
#
###############################################################################
ENTRY(irq_handler)
add -4,sp
SAVE_ALL
# it's not a syscall
mov 0xffffffff,d0
mov d0,(REG_ORIG_D0,fp)
mov fp,d0
call do_IRQ[],0 # do_IRQ(regs)
jmp ret_from_intr
###############################################################################
#
# Double Fault handler entry point
# - note that there will not be a stack, D0/A0 will hold EPSW/PC as were
#
###############################################################################
.section .bss
.balign THREAD_SIZE
.space THREAD_SIZE
__df_stack:
.previous
ENTRY(double_fault)
mov a0,(__df_stack-4) # PC as was
mov d0,(__df_stack-8) # EPSW as was
mn10300_set_dbfleds # display 'db-f' on the LEDs
mov 0xaa55aa55,d0
mov d0,(__df_stack-12) # no ORIG_D0
mov sp,a0 # save corrupted SP
mov __df_stack-12,sp # emergency supervisor stack
SAVE_ALL
mov a0,(REG_A0,fp) # save corrupted SP as A0 (which got
# clobbered by the CPU)
mov fp,d0
calls do_double_fault
double_fault_loop:
bra double_fault_loop
###############################################################################
#
# Bus Error handler entry point
# - handle external (async) bus errors separately
#
###############################################################################
ENTRY(raw_bus_error)
add -4,sp
mov d0,(sp)
#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
mov (MMUCTR),d0
mov d0,(MMUCTR)
#endif
mov (BCBERR),d0 # what
btst BCBERR_BEMR_DMA,d0 # see if it was an external bus error
beq __common_exception_aux # it wasn't
SAVE_ALL
mov (BCBEAR),d1 # destination of erroneous access
mov (REG_ORIG_D0,fp),d2
mov d2,(REG_D0,fp)
mov -1,d2
mov d2,(REG_ORIG_D0,fp)
add -4,sp
mov fp,(12,sp) # frame pointer
call io_bus_error[],0
jmp restore_all
###############################################################################
#
# NMI exception entry points
#
# This is used by ordinary interrupt channels that have the GxICR_NMI bit set
# in addition to the main NMI and Watchdog channels. SMP NMI IPIs use this
# facility.
#
###############################################################################
ENTRY(nmi_handler)
add -4,sp
mov d0,(sp)
mov (TBR),d0
#ifdef CONFIG_SMP
add -4,sp
mov d0,(sp) # save d0(TBR)
movhu (NMIAGR),d0
and NMIAGR_GN,d0
lsr 0x2,d0
cmp CALL_FUNCTION_NMI_IPI,d0
bne nmi_not_smp_callfunc # if not call function, jump
# function call nmi ipi
add 4,sp # no need to store TBR
mov GxICR_DETECT,d0 # clear NMI request
movbu d0,(GxICR(CALL_FUNCTION_NMI_IPI))
movhu (GxICR(CALL_FUNCTION_NMI_IPI)),d0
and ~EPSW_NMID,epsw # enable NMI
mov (sp),d0 # restore d0
SAVE_ALL
call smp_nmi_call_function_interrupt[],0
RESTORE_ALL
nmi_not_smp_callfunc:
#ifdef CONFIG_KERNEL_DEBUGGER
cmp DEBUGGER_NMI_IPI,d0
bne nmi_not_debugger # if not kernel debugger NMI IPI, jump
# kernel debugger NMI IPI
add 4,sp # no need to store TBR
mov GxICR_DETECT,d0 # clear NMI
movbu d0,(GxICR(DEBUGGER_NMI_IPI))
movhu (GxICR(DEBUGGER_NMI_IPI)),d0
and ~EPSW_NMID,epsw # enable NMI
mov (sp),d0
SAVE_ALL
mov fp,d0 # arg 0: stacked register file
mov a2,d1 # arg 1: exception number
call debugger_nmi_interrupt[],0
RESTORE_ALL
nmi_not_debugger:
#endif /* CONFIG_KERNEL_DEBUGGER */
mov (sp),d0 # restore TBR to d0
add 4,sp
#endif /* CONFIG_SMP */
bra __common_exception_nonmi
###############################################################################
#
# General exception entry point
#
###############################################################################
ENTRY(__common_exception)
add -4,sp
mov d0,(sp)
#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
mov (MMUCTR),d0
mov d0,(MMUCTR)
#endif
__common_exception_aux:
mov (TBR),d0
and ~EPSW_NMID,epsw # turn NMIs back on if not NMI
or EPSW_IE,epsw
__common_exception_nonmi:
and 0x0000FFFF,d0 # turn the exception code into a vector
# table index
btst 0x00000007,d0
bne 1f
cmp 0x00000400,d0
bge 1f
SAVE_ALL # build the stack frame
mov (REG_D0,fp),a2 # get the exception number
mov (REG_ORIG_D0,fp),d0
mov d0,(REG_D0,fp)
mov -1,d0
mov d0,(REG_ORIG_D0,fp)
#ifdef CONFIG_GDBSTUB
#ifdef CONFIG_SMP
call gdbstub_busy_check[],0
and d0,d0 # check return value
beq 2f
#else /* CONFIG_SMP */
btst 0x01,(gdbstub_busy)
beq 2f
#endif /* CONFIG_SMP */
and ~EPSW_IE,epsw
mov fp,d0
mov a2,d1
call gdbstub_exception[],0 # gdbstub itself caused an exception
bra restore_all
2:
#endif /* CONFIG_GDBSTUB */
mov fp,d0 # arg 0: stacked register file
mov a2,d1 # arg 1: exception number
lsr 1,a2
mov (exception_table,a2),a2
calls (a2)
jmp ret_from_exception
1: pi # BUG() equivalent
###############################################################################
#
# Exception handler functions table
#
###############################################################################
.data
ENTRY(exception_table)
.rept 0x400>>1
.long uninitialised_exception
.endr
.previous
###############################################################################
#
# Change an entry in the exception table
# - D0 exception code, D1 handler
#
###############################################################################
ENTRY(set_excp_vector)
lsr 1,d0
add exception_table,d0
mov d1,(d0)
mov 4,d1
ret [],0
###############################################################################
#
# System call table
#
###############################################################################
.data
ENTRY(sys_call_table)
.long sys_restart_syscall /* 0 */
.long sys_exit
.long sys_fork
.long sys_read
.long sys_write
.long sys_open /* 5 */
.long sys_close
.long sys_waitpid
.long sys_creat
.long sys_link
.long sys_unlink /* 10 */
.long sys_execve
.long sys_chdir
.long sys_time
.long sys_mknod
.long sys_chmod /* 15 */
.long sys_lchown16
.long sys_ni_syscall /* old break syscall holder */
.long sys_stat
.long sys_lseek
.long sys_getpid /* 20 */
.long sys_mount
.long sys_oldumount
.long sys_setuid16
.long sys_getuid16
.long sys_stime /* 25 */
.long sys_ptrace
.long sys_alarm
.long sys_fstat
.long sys_pause
.long sys_utime /* 30 */
.long sys_ni_syscall /* old stty syscall holder */
.long sys_ni_syscall /* old gtty syscall holder */
.long sys_access
.long sys_nice
.long sys_ni_syscall /* 35 - old ftime syscall holder */
.long sys_sync
.long sys_kill
.long sys_rename
.long sys_mkdir
.long sys_rmdir /* 40 */
.long sys_dup
.long sys_pipe
.long sys_times
.long sys_ni_syscall /* old prof syscall holder */
.long sys_brk /* 45 */
.long sys_setgid16
.long sys_getgid16
.long sys_signal
.long sys_geteuid16
.long sys_getegid16 /* 50 */
.long sys_acct
.long sys_umount /* recycled never used phys() */
.long sys_ni_syscall /* old lock syscall holder */
.long sys_ioctl
.long sys_fcntl /* 55 */
.long sys_ni_syscall /* old mpx syscall holder */
.long sys_setpgid
.long sys_ni_syscall /* old ulimit syscall holder */
.long sys_ni_syscall /* old sys_olduname */
.long sys_umask /* 60 */
.long sys_chroot
.long sys_ustat
.long sys_dup2
.long sys_getppid
.long sys_getpgrp /* 65 */
.long sys_setsid
.long sys_sigaction
.long sys_sgetmask
.long sys_ssetmask
.long sys_setreuid16 /* 70 */
.long sys_setregid16
.long sys_sigsuspend
.long sys_sigpending
.long sys_sethostname
.long sys_setrlimit /* 75 */
.long sys_old_getrlimit
.long sys_getrusage
.long sys_gettimeofday
.long sys_settimeofday
.long sys_getgroups16 /* 80 */
.long sys_setgroups16
.long sys_old_select
.long sys_symlink
.long sys_lstat
.long sys_readlink /* 85 */
.long sys_uselib
.long sys_swapon
.long sys_reboot
.long sys_old_readdir
.long old_mmap /* 90 */
.long sys_munmap
.long sys_truncate
.long sys_ftruncate
.long sys_fchmod
.long sys_fchown16 /* 95 */
.long sys_getpriority
.long sys_setpriority
.long sys_ni_syscall /* old profil syscall holder */
.long sys_statfs
.long sys_fstatfs /* 100 */
.long sys_ni_syscall /* ioperm */
.long sys_socketcall
.long sys_syslog
.long sys_setitimer
.long sys_getitimer /* 105 */
.long sys_newstat
.long sys_newlstat
.long sys_newfstat
.long sys_ni_syscall /* old sys_uname */
.long sys_ni_syscall /* 110 - iopl */
.long sys_vhangup
.long sys_ni_syscall /* old "idle" system call */
.long sys_ni_syscall /* vm86old */
.long sys_wait4
.long sys_swapoff /* 115 */
.long sys_sysinfo
.long sys_ipc
.long sys_fsync
.long sys_sigreturn
.long sys_clone /* 120 */
.long sys_setdomainname
.long sys_newuname
.long sys_ni_syscall /* modify_ldt */
.long sys_adjtimex
.long sys_mprotect /* 125 */
.long sys_sigprocmask
.long sys_ni_syscall /* old "create_module" */
.long sys_init_module
.long sys_delete_module
.long sys_ni_syscall /* 130: old "get_kernel_syms" */
.long sys_quotactl
.long sys_getpgid
.long sys_fchdir
.long sys_bdflush
.long sys_sysfs /* 135 */
.long sys_personality
.long sys_ni_syscall /* reserved for afs_syscall */
.long sys_setfsuid16
.long sys_setfsgid16
.long sys_llseek /* 140 */
.long sys_getdents
.long sys_select
.long sys_flock
.long sys_msync
.long sys_readv /* 145 */
.long sys_writev
.long sys_getsid
.long sys_fdatasync
.long sys_sysctl
.long sys_mlock /* 150 */
.long sys_munlock
.long sys_mlockall
.long sys_munlockall
.long sys_sched_setparam
.long sys_sched_getparam /* 155 */
.long sys_sched_setscheduler
.long sys_sched_getscheduler
.long sys_sched_yield
.long sys_sched_get_priority_max
.long sys_sched_get_priority_min /* 160 */
.long sys_sched_rr_get_interval
.long sys_nanosleep
.long sys_mremap
.long sys_setresuid16
.long sys_getresuid16 /* 165 */
.long sys_ni_syscall /* vm86 */
.long sys_ni_syscall /* Old sys_query_module */
.long sys_poll
.long sys_ni_syscall /* was nfsservctl */
.long sys_setresgid16 /* 170 */
.long sys_getresgid16
.long sys_prctl
.long sys_rt_sigreturn
.long sys_rt_sigaction
.long sys_rt_sigprocmask /* 175 */
.long sys_rt_sigpending
.long sys_rt_sigtimedwait
.long sys_rt_sigqueueinfo
.long sys_rt_sigsuspend
.long sys_pread64 /* 180 */
.long sys_pwrite64
.long sys_chown16
.long sys_getcwd
.long sys_capget
.long sys_capset /* 185 */
.long sys_sigaltstack
.long sys_sendfile
.long sys_ni_syscall /* reserved for streams1 */
.long sys_ni_syscall /* reserved for streams2 */
.long sys_vfork /* 190 */
.long sys_getrlimit
.long sys_mmap_pgoff
.long sys_truncate64
.long sys_ftruncate64
.long sys_stat64 /* 195 */
.long sys_lstat64
.long sys_fstat64
.long sys_lchown
.long sys_getuid
.long sys_getgid /* 200 */
.long sys_geteuid
.long sys_getegid
.long sys_setreuid
.long sys_setregid
.long sys_getgroups /* 205 */
.long sys_setgroups
.long sys_fchown
.long sys_setresuid
.long sys_getresuid
.long sys_setresgid /* 210 */
.long sys_getresgid
.long sys_chown
.long sys_setuid
.long sys_setgid
.long sys_setfsuid /* 215 */
.long sys_setfsgid
.long sys_pivot_root
.long sys_mincore
.long sys_madvise
.long sys_getdents64 /* 220 */
.long sys_fcntl64
.long sys_ni_syscall /* reserved for TUX */
.long sys_ni_syscall
.long sys_gettid
.long sys_readahead /* 225 */
.long sys_setxattr
.long sys_lsetxattr
.long sys_fsetxattr
.long sys_getxattr
.long sys_lgetxattr /* 230 */
.long sys_fgetxattr
.long sys_listxattr
.long sys_llistxattr
.long sys_flistxattr
.long sys_removexattr /* 235 */
.long sys_lremovexattr
.long sys_fremovexattr
.long sys_tkill
.long sys_sendfile64
.long sys_futex /* 240 */
.long sys_sched_setaffinity
.long sys_sched_getaffinity
.long sys_ni_syscall /* sys_set_thread_area */
.long sys_ni_syscall /* sys_get_thread_area */
.long sys_io_setup /* 245 */
.long sys_io_destroy
.long sys_io_getevents
.long sys_io_submit
.long sys_io_cancel
.long sys_fadvise64 /* 250 */
.long sys_ni_syscall
.long sys_exit_group
.long sys_lookup_dcookie
.long sys_epoll_create
.long sys_epoll_ctl /* 255 */
.long sys_epoll_wait
.long sys_remap_file_pages
.long sys_set_tid_address
.long sys_timer_create
.long sys_timer_settime /* 260 */
.long sys_timer_gettime
.long sys_timer_getoverrun
.long sys_timer_delete
.long sys_clock_settime
.long sys_clock_gettime /* 265 */
.long sys_clock_getres
.long sys_clock_nanosleep
.long sys_statfs64
.long sys_fstatfs64
.long sys_tgkill /* 270 */
.long sys_utimes
.long sys_fadvise64_64
.long sys_ni_syscall /* sys_vserver */
.long sys_mbind
.long sys_get_mempolicy /* 275 */
.long sys_set_mempolicy
.long sys_mq_open
.long sys_mq_unlink
.long sys_mq_timedsend
.long sys_mq_timedreceive /* 280 */
.long sys_mq_notify
.long sys_mq_getsetattr
.long sys_kexec_load
.long sys_waitid
.long sys_ni_syscall /* 285 */ /* available */
.long sys_add_key
.long sys_request_key
.long sys_keyctl
.long sys_cacheflush
.long sys_ioprio_set /* 290 */
.long sys_ioprio_get
.long sys_inotify_init
.long sys_inotify_add_watch
.long sys_inotify_rm_watch
.long sys_migrate_pages /* 295 */
.long sys_openat
.long sys_mkdirat
.long sys_mknodat
.long sys_fchownat
.long sys_futimesat /* 300 */
.long sys_fstatat64
.long sys_unlinkat
.long sys_renameat
.long sys_linkat
.long sys_symlinkat /* 305 */
.long sys_readlinkat
.long sys_fchmodat
.long sys_faccessat
.long sys_pselect6
.long sys_ppoll /* 310 */
.long sys_unshare
.long sys_set_robust_list
.long sys_get_robust_list
.long sys_splice
.long sys_sync_file_range /* 315 */
.long sys_tee
.long sys_vmsplice
.long sys_move_pages
.long sys_getcpu
.long sys_epoll_pwait /* 320 */
.long sys_utimensat
.long sys_signalfd
.long sys_timerfd_create
.long sys_eventfd
.long sys_fallocate /* 325 */
.long sys_timerfd_settime
.long sys_timerfd_gettime
.long sys_signalfd4
.long sys_eventfd2
.long sys_epoll_create1 /* 330 */
.long sys_dup3
.long sys_pipe2
.long sys_inotify_init1
.long sys_preadv
.long sys_pwritev /* 335 */
.long sys_rt_tgsigqueueinfo
.long sys_perf_event_open
.long sys_recvmmsg
.long sys_setns
nr_syscalls=(.-sys_call_table)/4