diff options
Diffstat (limited to 'arch/arm/kernel/entry-common.S')
| -rw-r--r-- | arch/arm/kernel/entry-common.S | 82 |
1 files changed, 68 insertions, 14 deletions
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index f05a35a5969..8bfa98757cd 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -48,6 +48,8 @@ work_pending: beq no_work_pending mov r0, sp @ 'regs' mov r2, why @ 'syscall' + tst r1, #_TIF_SIGPENDING @ delivering a signal? + movne why, #0 @ prevent further restarts bl do_notify_resume b ret_slow_syscall @ Check work again @@ -127,30 +129,58 @@ ENDPROC(ret_from_fork) * clobber the ip register. This is OK because the ARM calling convention * allows it to be clobbered in subroutines and doesn't use it to hold * parameters.) + * + * When using dynamic ftrace, we patch out the mcount call by a "mov r0, r0" + * for the mcount case, and a "pop {lr}" for the __gnu_mcount_nc case (see + * arch/arm/kernel/ftrace.c). */ + +#ifndef CONFIG_OLD_MCOUNT +#if (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 4)) +#error Ftrace requires CONFIG_FRAME_POINTER=y with GCC older than 4.4.0. +#endif +#endif + #ifdef CONFIG_DYNAMIC_FTRACE -ENTRY(mcount) +ENTRY(__gnu_mcount_nc) + mov ip, lr + ldmia sp!, {lr} + mov pc, ip +ENDPROC(__gnu_mcount_nc) + +ENTRY(ftrace_caller) stmdb sp!, {r0-r3, lr} mov r0, lr sub r0, r0, #MCOUNT_INSN_SIZE + ldr r1, [sp, #20] - .globl mcount_call -mcount_call: + .global ftrace_call +ftrace_call: bl ftrace_stub - ldr lr, [fp, #-4] @ restore lr - ldmia sp!, {r0-r3, pc} + ldmia sp!, {r0-r3, ip, lr} + mov pc, ip +ENDPROC(ftrace_caller) -ENTRY(ftrace_caller) +#ifdef CONFIG_OLD_MCOUNT +ENTRY(mcount) + stmdb sp!, {lr} + ldr lr, [fp, #-4] + ldmia sp!, {pc} +ENDPROC(mcount) + +ENTRY(ftrace_caller_old) stmdb sp!, {r0-r3, lr} ldr r1, [fp, #-4] mov r0, lr sub r0, r0, #MCOUNT_INSN_SIZE - .globl ftrace_call -ftrace_call: + .globl ftrace_call_old +ftrace_call_old: bl ftrace_stub ldr lr, [fp, #-4] @ restore lr ldmia sp!, {r0-r3, pc} +ENDPROC(ftrace_caller_old) +#endif #else @@ -158,7 +188,7 @@ ENTRY(__gnu_mcount_nc) stmdb sp!, {r0-r3, lr} ldr r0, =ftrace_trace_function ldr r2, [r0] - adr r0, ftrace_stub + adr r0, .Lftrace_stub cmp r0, r2 bne gnu_trace ldmia sp!, {r0-r3, ip, lr} @@ -168,11 +198,19 @@ gnu_trace: ldr r1, [sp, #20] @ lr of instrumented routine mov r0, lr sub r0, r0, #MCOUNT_INSN_SIZE - mov lr, pc + adr lr, BSYM(1f) mov pc, r2 +1: ldmia sp!, {r0-r3, ip, lr} mov pc, ip +ENDPROC(__gnu_mcount_nc) +#ifdef CONFIG_OLD_MCOUNT +/* + * This is under an ifdef in order to force link-time errors for people trying + * to build with !FRAME_POINTER with a GCC which doesn't use the new-style + * mcount. + */ ENTRY(mcount) stmdb sp!, {r0-r3, lr} ldr r0, =ftrace_trace_function @@ -191,12 +229,15 @@ trace: mov pc, r2 ldr lr, [fp, #-4] @ restore lr ldmia sp!, {r0-r3, pc} +ENDPROC(mcount) +#endif #endif /* CONFIG_DYNAMIC_FTRACE */ - .globl ftrace_stub -ftrace_stub: +ENTRY(ftrace_stub) +.Lftrace_stub: mov pc, lr +ENDPROC(ftrace_stub) #endif /* CONFIG_FUNCTION_TRACER */ @@ -293,7 +334,6 @@ ENTRY(vector_swi) get_thread_info tsk adr tbl, sys_call_table @ load syscall table pointer - ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing #if defined(CONFIG_OABI_COMPAT) /* @@ -310,8 +350,20 @@ ENTRY(vector_swi) eor scno, scno, #__NR_SYSCALL_BASE @ check OS number #endif + ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing stmdb sp!, {r4, r5} @ push fifth and sixth args - tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls? + +#ifdef CONFIG_SECCOMP + tst r10, #_TIF_SECCOMP + beq 1f + mov r0, scno + bl __secure_computing + add r0, sp, #S_R0 + S_OFF @ pointer to regs + ldmia r0, {r0 - r3} @ have to reload r0 - r3 +1: +#endif + + tst r10, #_TIF_SYSCALL_TRACE @ are we tracing syscalls? bne __sys_trace cmp scno, #NR_syscalls @ check upper syscall limit @@ -418,11 +470,13 @@ ENDPROC(sys_clone_wrapper) sys_sigreturn_wrapper: add r0, sp, #S_OFF + mov why, #0 @ prevent syscall restart handling b sys_sigreturn ENDPROC(sys_sigreturn_wrapper) sys_rt_sigreturn_wrapper: add r0, sp, #S_OFF + mov why, #0 @ prevent syscall restart handling b sys_rt_sigreturn ENDPROC(sys_rt_sigreturn_wrapper) |