diff options
Diffstat (limited to 'arch/arm/kernel/entry-common.S')
| -rw-r--r-- | arch/arm/kernel/entry-common.S | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index e33c32d56193..ca3614dc6938 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -27,6 +27,14 @@ #include "entry-header.S" +saved_psr .req r8 +#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING) +saved_pc .req r9 +#define TRACE(x...) x +#else +saved_pc .req lr +#define TRACE(x...) +#endif .align 5 #if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING)) @@ -146,16 +154,17 @@ ENTRY(vector_swi) ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr THUMB( mov r8, sp ) THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr - mrs r8, spsr @ called from non-FIQ mode, so ok. - str lr, [sp, #S_PC] @ Save calling PC - str r8, [sp, #S_PSR] @ Save CPSR + mrs saved_psr, spsr @ called from non-FIQ mode, so ok. + TRACE( mov saved_pc, lr ) + str saved_pc, [sp, #S_PC] @ Save calling PC + str saved_psr, [sp, #S_PSR] @ Save CPSR str r0, [sp, #S_OLD_R0] @ Save OLD_R0 #endif zero_fp alignment_trap r10, ip, __cr_alignment - enable_irq - ct_user_exit - get_thread_info tsk + asm_trace_hardirqs_on save=0 + enable_irq_notrace + ct_user_exit save=0 /* * Get the system call number. @@ -168,11 +177,11 @@ ENTRY(vector_swi) * value to determine if it is an EABI or an old ABI call. */ #ifdef CONFIG_ARM_THUMB - tst r8, #PSR_T_BIT + tst saved_psr, #PSR_T_BIT movne r10, #0 @ no thumb OABI emulation - USER( ldreq r10, [lr, #-4] ) @ get SWI instruction + USER( ldreq r10, [saved_pc, #-4] ) @ get SWI instruction #else - USER( ldr r10, [lr, #-4] ) @ get SWI instruction + USER( ldr r10, [saved_pc, #-4] ) @ get SWI instruction #endif ARM_BE8(rev r10, r10) @ little endian instruction @@ -183,15 +192,17 @@ ENTRY(vector_swi) */ #elif defined(CONFIG_ARM_THUMB) /* Legacy ABI only, possibly thumb mode. */ - tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs + tst saved_psr, #PSR_T_BIT @ this is SPSR from save_user_regs addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in - USER( ldreq scno, [lr, #-4] ) + USER( ldreq scno, [saved_pc, #-4] ) #else /* Legacy ABI only. */ - USER( ldr scno, [lr, #-4] ) @ get SWI instruction + USER( ldr scno, [saved_pc, #-4] ) @ get SWI instruction #endif + /* saved_psr and saved_pc are now dead */ + uaccess_disable tbl adr tbl, sys_call_table @ load syscall table pointer @@ -210,6 +221,12 @@ ENTRY(vector_swi) bic scno, scno, #0xff000000 @ mask off SWI op-code eor scno, scno, #__NR_SYSCALL_BASE @ check OS number #endif + get_thread_info tsk + /* + * Reload the registers that may have been corrupted on entry to + * the syscall assembly (by tracing or context tracking.) + */ + TRACE( ldmia sp, {r0 - r3} ) local_restart: ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing @@ -239,8 +256,9 @@ local_restart: * current task. */ 9001: - sub lr, lr, #4 + sub lr, saved_pc, #4 str lr, [sp, #S_PC] + get_thread_info tsk b ret_fast_syscall #endif ENDPROC(vector_swi) |