From 283237a04fd332bddc2ac298e6ad7d23a1fc4b99 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Tue, 28 May 2013 09:34:45 +0530 Subject: ARC: pt_regs update #1: Align pt_regs end with end of kernel stack page Historically, pt_regs would end at offset of 1 word from end of stack page. ----------------- -> START of page (task->stack) | | | thread_info | ----------------- | | ^ ~ ~ | ~ ~ | | | | | | <---- pt_regs used to END here ----------------- | 1 word GUTTER | ----------------- -> End of page (START of kernel stack) This required special "one-off" considerations in low level code. The root cause is very likely assumption of "empty" SP by the original ARC kernel hackers, despite ARC700 always been "full" SP. So finally RIP one word gutter ! Signed-off-by: Vineet Gupta --- arch/arc/include/asm/entry.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arc/include/asm/entry.h') diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index 5bbec8ad812..2b274fa9c5a 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -252,7 +252,7 @@ ld \out, [\tsk, TASK_THREAD_INFO] /* Go to end of page where stack begins (grows upwards) */ - add2 \out, \out, (THREAD_SIZE - 4)/4 /* one word GUTTER */ + add2 \out, \out, (THREAD_SIZE)/4 .endm -- cgit v1.2.3-70-g09d2