d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Don't make assertions about td_critnest when the scheduler is stopped.

Browse Source 
A panicking thread always executes with a critical section held, so any
attempt to allocate or free memory while dumping will otherwise cause a
second panic. This can occur, for example, if xpt_polled_action() completes
non-dump I/O that was pending at the time of the panic. The fact that this
can occur is itself a bug, but asserting in this case does little but
reduce the reliability of kernel dumps.

Suggested by:	kib
Reported by:	pho
This commit is contained in:
markj 2015-12-11 20:05:07 +00:00
parent c90cc6d115
commit 98fd4878e0
2 changed files with 5 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sys/kern/kern_malloc.c
View File

@ -475,8 +475,7 @@ malloc(unsigned long size, struct malloc_type *mtp, int flags)
if (flags & M_WAITOK)
KASSERT(curthread->td_intr_nesting_level == 0,
("malloc(M_WAITOK) in interrupt context"));
KASSERT(curthread->td_critnest == 0,
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
("malloc: called with spinlock or critical section held"));
#ifdef DEBUG_MEMGUARD
@ -544,8 +543,7 @@ free(void *addr, struct malloc_type *mtp)
u_long size;
KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic"));
KASSERT(curthread->td_critnest == 0,
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
("free: called with spinlock or critical section held"));
/* free(NULL, ...) does nothing */
@ -610,8 +608,7 @@ realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags)
KASSERT(mtp->ks_magic == M_MAGIC,
("realloc: bad malloc type magic"));
KASSERT(curthread->td_critnest == 0,
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
("realloc: called with spinlock or critical section held"));
/* realloc(NULL, ...) is equivalent to malloc(...) */

5
sys/vm/uma_core.c
View File

@ -2149,8 +2149,7 @@ uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
"uma_zalloc_arg: zone \"%s\"", zone->uz_name);
}
KASSERT(curthread->td_critnest == 0,
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
("uma_zalloc_arg: called with spinlock or critical section held"));
#ifdef DEBUG_MEMGUARD
@ -2690,7 +2689,7 @@ uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
zone->uz_name);
KASSERT(curthread->td_critnest == 0,
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
("uma_zfree_arg: called with spinlock or critical section held"));
/* uma_zfree(..., NULL) does nothing, to match free(9). */