diff options
Diffstat (limited to 'arch/arc/include/asm/entry.h')
| -rw-r--r-- | arch/arc/include/asm/entry.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index 63705b12d91..6b42bf5c45e 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -166,6 +166,41 @@ .endm /*-------------------------------------------------------------- + * RESTORE_CALLEE_SAVED_USER: + * This is called after do_signal where tracer might have changed callee regs + * thus we need to restore the reg file. + * Special case handling is required for r25 in case it is used by kernel + * for caching task ptr. Ptrace would have modified on-kernel-stack value of + * r25, which needs to be shoved back into task->thread.user_r25 where from + * Low level exception/ISR return code will retrieve to populate with rest of + * callee reg-file. + *-------------------------------------------------------------*/ +.macro RESTORE_CALLEE_SAVED_USER + + add sp, sp, 4 /* skip "callee_regs->stack_place_holder" */ + +#ifdef CONFIG_ARC_CURR_IN_REG + ld.ab r12, [sp, 4] + st r12, [r25, TASK_THREAD + THREAD_USER_R25] +#else + ld.ab r25, [sp, 4] +#endif + + ld.ab r24, [sp, 4] + ld.ab r23, [sp, 4] + ld.ab r22, [sp, 4] + ld.ab r21, [sp, 4] + ld.ab r20, [sp, 4] + ld.ab r19, [sp, 4] + ld.ab r18, [sp, 4] + ld.ab r17, [sp, 4] + ld.ab r16, [sp, 4] + ld.ab r15, [sp, 4] + ld.ab r14, [sp, 4] + ld.ab r13, [sp, 4] +.endm + +/*-------------------------------------------------------------- * Super FAST Restore callee saved regs by simply re-adjusting SP *-------------------------------------------------------------*/ .macro DISCARD_CALLEE_SAVED_USER |