diff options
| author | alc <alc@FreeBSD.org> | 1999-03-16 07:39:07 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 1999-03-16 07:39:07 +0000 |
| commit | 57d921a394105859ef749c2f1a49b291925ed38d (patch) | |
| tree | 0ec30c28e75820546aeae059c0cd308f12bd585d /sys/vm/vm_kern.c | |
| parent | f7a7179f0fecc8d4e0dfb40980a3f903f39c5271 (diff) | |
| download | FreeBSD-src-57d921a394105859ef749c2f1a49b291925ed38d.zip FreeBSD-src-57d921a394105859ef749c2f1a49b291925ed38d.tar.gz | |
Correct a problem in kmem_malloc: A kmem_malloc allowing "wait" may
block (VM_WAIT) holding the map lock. This is bad. For example, a subsequent
kmem_malloc by an interrupt handler on the same map may find the lock held
and panic in the lockmgr.
Diffstat (limited to 'sys/vm/vm_kern.c')
| -rw-r--r-- | sys/vm/vm_kern.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/sys/vm/vm_kern.c b/sys/vm/vm_kern.c index d4feb44..16c6208 100644 --- a/sys/vm/vm_kern.c +++ b/sys/vm/vm_kern.c @@ -61,7 +61,7 @@ * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. * - * $Id: vm_kern.c,v 1.52 1999/01/21 09:38:20 dillon Exp $ + * $Id: vm_kern.c,v 1.53 1999/03/12 08:05:49 alc Exp $ */ /* @@ -337,7 +337,9 @@ retry: */ if (m == NULL) { if ((flags & M_NOWAIT) == 0) { + vm_map_unlock(map); VM_WAIT; + vm_map_lock(map); goto retry; } vm_map_delete(map, addr, addr + size); @@ -359,9 +361,9 @@ retry: */ if (!vm_map_lookup_entry(map, addr, &entry) || entry->start != addr || entry->end != addr + size || - entry->wired_count) + entry->wired_count != 0) panic("kmem_malloc: entry not found or misaligned"); - entry->wired_count++; + entry->wired_count = 1; vm_map_simplify_entry(map, entry); |
