From 05dc16d6a175139a5872d08db56ee277ec90df5b Mon Sep 17 00:00:00 2001 From: Randolph Chung Date: Tue, 12 Jun 2007 14:27:32 +0800 Subject: [PATCH] [PARISC] unwinder improvements Add special-case handling for "handle_interruption" so that we can rewind past the interruption. This is useful for seeing what caused a BUG() or WARN_ON(); otherwise the unwind stops at the interruption. Signed-off-by: Randolph Chung Signed-off-by: Kyle McMartin --- arch/parisc/kernel/unwind.c | 41 ++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c index cad9d78312..322167737d 100644 --- a/arch/parisc/kernel/unwind.c +++ b/arch/parisc/kernel/unwind.c @@ -16,6 +16,8 @@ #include #include +#include +#include #include @@ -199,6 +201,29 @@ static int unwind_init(void) return 0; } +#ifdef CONFIG_64BIT +#define get_func_addr(fptr) fptr[2] +#else +#define get_func_addr(fptr) fptr[0] +#endif + +static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int frame_size) +{ + void handle_interruption(int, struct pt_regs *); + static unsigned long *hi = (unsigned long)&handle_interruption; + + if (pc == get_func_addr(hi)) { + struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN); + dbg("Unwinding through handle_interruption()\n"); + info->prev_sp = regs->gr[30]; + info->prev_ip = regs->iaoq[0]; + + return 1; + } + + return 0; +} + static void unwind_frame_regs(struct unwind_frame_info *info) { const struct unwind_table_entry *e; @@ -312,13 +337,15 @@ static void unwind_frame_regs(struct unwind_frame_info *info) } } - info->prev_sp = info->sp - frame_size; - if (e->Millicode) - info->rp = info->r31; - else if (rpoffset) - info->rp = *(unsigned long *)(info->prev_sp - rpoffset); - info->prev_ip = info->rp; - info->rp = 0; + if (!unwind_special(info, e->region_start, frame_size)) { + info->prev_sp = info->sp - frame_size; + if (e->Millicode) + info->rp = info->r31; + else if (rpoffset) + info->rp = *(unsigned long *)(info->prev_sp - rpoffset); + info->prev_ip = info->rp; + info->rp = 0; + } dbg("analyzing func @ %lx, setting prev_sp=%lx " "prev_ip=%lx npc=%lx\n", info->ip, info->prev_sp, -- 2.39.5