traps, unwind new patch proposal.
Hi Randolph and *,
Here is my new proposal to attempt to fix the show_stack() bug in the early boot stage:
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 renamed from asm-parisc/unwind.h.Orig 2005-05-01 15:55:25.000000000 +0200 +11 -1
@@ -61,6 +61,14 @@ unsigned long prev_sp, prev_ip; }; +struct unwind_frame_regs { + unsigned long sp, ip, rp, r31; +}; + +#define UFI_REGS_BUF_MAX 128 /* about 4k for LP64 */ +extern struct unwind_frame_regs ufi_regs_buf[UFI_REGS_BUF_MAX]; +extern unsigned int ufi_regs_buf_i; + struct unwind_table * unwind_table_add(const char *name, unsigned long base_addr, unsigned long gp, void *start, void *end);
@@ -68,9 +76,11 @@ unwind_table_remove(struct unwind_table *table); void unwind_frame_init(struct unwind_frame_info *info, struct task_struct *t, - struct pt_regs *regs); + struct unwind_frame_regs *regs); void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info, struct task_struct *t); +#if 0 /* FIXME: not used */ void unwind_frame_init_running(struct unwind_frame_info *info, struct pt_regs *regs); +#endif int unwind_once(struct unwind_frame_info *info); int unwind_to_user(struct unwind_frame_info *info);
parisc/kernel/unwind.c 2005-05-01 15:40:39.000000000 +0200 renamed from parisc/kernel/unwind.c.Orig 2005-05-01 15:50:50.000000000 +0200 +18 -15
@@ -326,14 +326,18 @@ } void unwind_frame_init(struct unwind_frame_info *info, struct task_struct *t, - struct pt_regs *regs) + struct unwind_frame_regs *regs) { - memset(info, 0, sizeof(struct unwind_frame_info)); + if (unlikely(!info)) { + printk(KERN_ERR "%s: info == NULL\n", __FUNCTION__); + return; + } + memset(info, 0, sizeof(*info)); info->t = t; - info->sp = regs->gr[30]; - info->ip = regs->iaoq[0]; - info->rp = regs->gr[2]; - info->r31 = regs->gr[31]; + info->sp = regs->sp; + info->ip = regs->ip; + info->rp = regs->rp; + info->r31 = regs->r31; dbg("(%d) Start unwind from sp=%08lx ip=%08lx\n", t ? (int)t->pid : -1, info->sp, info->ip);
@@ -342,22 +346,21 @@ void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info, struct task_struct *t) { struct pt_regs *r = &t->thread.regs; - struct pt_regs *r2; + struct unwind_frame_regs r2; - r2 = (struct pt_regs *)kmalloc(sizeof(struct pt_regs), GFP_KERNEL); - if (!r2) - return; - *r2 = *r; - r2->gr[30] = r->ksp; - r2->iaoq[0] = r->kpc; - unwind_frame_init(info, t, r2); - kfree(r2); + r2.sp = r->ksp; + r2.ip = r->kpc; + r2.rp = r->gr[2]; + r2.r31 = r->gr[31]; + unwind_frame_init(info, t, &r2); } +#if 0 /* FIXME: not used */ void unwind_frame_init_running(struct unwind_frame_info *info, struct pt_regs *regs) { unwind_frame_init(info, current, regs); } +#endif int unwind_once(struct unwind_frame_info *next_frame) {
parisc/kernel/traps.c 2005-05-01 15:38:08.000000000 +0200 renamed from parisc/kernel/traps.c.Orig 2005-05-01 15:50:32.000000000 +0200 +23 -10
@@ -158,25 +158,35 @@ printk("\n"); } +struct unwind_frame_regs ufi_regs_buf[UFI_REGS_BUF_MAX]; +unsigned int ufi_regs_buf_i = 0; + void show_stack(struct task_struct *task, unsigned long *s) { struct unwind_frame_info info; + struct unwind_frame_regs *r; if (!task) { + if (ufi_regs_buf_i >= UFI_REGS_BUF_MAX) { + printk(KERN_ERR "Can't %s().\n", __FUNCTION__); + return; + } + unsigned long sp; - struct pt_regs *r; HERE: asm volatile ("copy %%r30, %0" : "=r"(sp)); - r = (struct pt_regs *)kmalloc(sizeof(struct pt_regs), GFP_KERNEL); - if (!r) - return; - memset(r, 0, sizeof(struct pt_regs)); - r->iaoq[0] = (unsigned long)&&HERE; - r->gr[2] = (unsigned long)__builtin_return_address(0); - r->gr[30] = sp; + r = &ufi_regs_buf[ufi_regs_buf_i++]; + memset(r, 0, sizeof(*r)); + r->ip = (unsigned long)&&HERE; + r->rp = (unsigned long)__builtin_return_address(0); + r->sp = sp; unwind_frame_init(&info, current, r); - kfree(r); + ufi_regs_buf_i--; + if (ufi_regs_buf_i < 0) { + printk(KERN_ERR "Wouldn't have reach here???\n"); + return; + } } else { unwind_frame_init_from_blocked_task(&info, task); }
@@ -423,7 +433,10 @@ { /* show_stack(NULL, (unsigned long *)regs->gr[30]); */ struct unwind_frame_info info; - unwind_frame_init(&info, current, regs); + struct unwind_frame_regs r2; + r2.sp = regs->gr[30]; r2.ip = regs->iaoq[0]; + r2.rp = regs->gr[2]; r2.r31 = regs->gr[31]; + unwind_frame_init(&info, current, &r2); do_show_stack(&info); }
====<>====
compile and boot fine on c110.
Thanks for additional advise,
Joel
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Joel,
Quoted 2 lines
Here is my new proposal to attempt to fix the
show_stack()bug in the early boot stage:
Can you explain again what is the problem you are seeing? Is it because of stack overflow? calls to kmalloc()?
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 line 66
Quoted 3 lines
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 renamed from asm-parisc/unwind.h.Orig 2005-05-01 15:55:25.000000000 +0200 +3
-0+struct unwind_frame_regs { + unsigned long sp, ip, rp, r31; +};
this is better, although i am still not very clear why we can't just use pt_regs.
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 line 70
Quoted 3 lines
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 renamed from asm-parisc/unwind.h.Orig 2005-05-01 15:55:25.000000000 +0200 +3
-0+#define UFI_REGS_BUF_MAX 128 /* about 4k for LP64 */ +extern struct unwind_frame_regs ufi_regs_buf[UFI_REGS_BUF_MAX]; +extern unsigned int ufi_regs_buf_i;
this seems to be used to handle recursive calls to show_stack(), is that right? why do we want to call show_stack() recursively?
i'm not sure why you want to put this array as a global variable. what's wrong with putting it on the stack of show_stack()?
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 line 83
Quoted 4 lines
asm-parisc/unwind.h 2005-05-01 15:23:56.000000000 +0200 renamed from asm-parisc/unwind.h.Orig 2005-05-01 15:55:25.000000000 +0200 +2
-0+#if 0 /* FIXME: not used */ void unwind_frame_init_running(struct unwind_frame_info *info, struct pt_regs *regs); +#endif
please fix this. this function is useful e.g. for kdb.
randolph
Signature · 7 lines
Randolph Chung Debian GNU/Linux Developer, hppa/ia64 ports http://www.tausq.org/ _______________________________________________ parisc-linux mailing list [email protected] http://lists.parisc-linux.org/mailman/listinfo/parisc-linux