diff options
Diffstat (limited to 'arch/arm/kernel/entry-common.S')
| -rw-r--r-- | arch/arm/kernel/entry-common.S | 46 |
1 files changed, 30 insertions, 16 deletions
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index bc5bc0a97131..11d68917d3b1 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -362,6 +362,16 @@ ENTRY(vector_swi) str r0, [sp, #S_OLD_R0] @ Save OLD_R0 zero_fp +#ifdef CONFIG_ALIGNMENT_TRAP + ldr ip, __cr_alignment + ldr ip, [ip] + mcr p15, 0, ip, c1, c0 @ update control register +#endif + + enable_irq + ct_user_exit + get_thread_info tsk + /* * Get the system call number. */ @@ -375,13 +385,11 @@ ENTRY(vector_swi) #ifdef CONFIG_ARM_THUMB tst r8, #PSR_T_BIT movne r10, #0 @ no thumb OABI emulation - ldreq r10, [lr, #-4] @ get SWI instruction + USER( ldreq r10, [lr, #-4] ) @ get SWI instruction #else - ldr r10, [lr, #-4] @ get SWI instruction -#endif -#ifdef CONFIG_CPU_ENDIAN_BE8 - rev r10, r10 @ little endian instruction + USER( ldr r10, [lr, #-4] ) @ get SWI instruction #endif + ARM_BE8(rev r10, r10) @ little endian instruction #elif defined(CONFIG_AEABI) @@ -392,22 +400,13 @@ ENTRY(vector_swi) /* Legacy ABI only, possibly thumb mode. */ tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in - ldreq scno, [lr, #-4] + USER( ldreq scno, [lr, #-4] ) #else /* Legacy ABI only. */ - ldr scno, [lr, #-4] @ get SWI instruction -#endif - -#ifdef CONFIG_ALIGNMENT_TRAP - ldr ip, __cr_alignment - ldr ip, [ip] - mcr p15, 0, ip, c1, c0 @ update control register + USER( ldr scno, [lr, #-4] ) @ get SWI instruction #endif - enable_irq - ct_user_exit - get_thread_info tsk adr tbl, sys_call_table @ load syscall table pointer #if defined(CONFIG_OABI_COMPAT) @@ -442,6 +441,21 @@ local_restart: eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back bcs arm_syscall b sys_ni_syscall @ not private func + +#if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI) + /* + * We failed to handle a fault trying to access the page + * containing the swi instruction, but we're not really in a + * position to return -EFAULT. Instead, return back to the + * instruction and re-enter the user fault handling path trying + * to page it in. This will likely result in sending SEGV to the + * current task. + */ +9001: + sub lr, lr, #4 + str lr, [sp, #S_PC] + b ret_fast_syscall +#endif ENDPROC(vector_swi) /* |