From 6fbe60fa8bedee712f8aa5c968fdfff5f33e0cb7 Mon Sep 17 00:00:00 2001 From: John Baldwin Date: Wed, 20 Jun 2012 18:00:26 +0000 Subject: [PATCH] Move the per-thread deferred user map entries list into a private list in vm_map_process_deferred() which is then iterated to release map entries. This avoids having a nested vm map unlock operation called from the loop body attempt to recuse into vm_map_process_deferred(). This can happen if the vm_map_remove() triggers the OOM killer. Reviewed by: alc, kib MFC after: 1 week --- sys/vm/vm_map.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c index f95fd82db06..5cb1fef1e56 100644 --- a/sys/vm/vm_map.c +++ b/sys/vm/vm_map.c @@ -475,12 +475,14 @@ static void vm_map_process_deferred(void) { struct thread *td; - vm_map_entry_t entry; + vm_map_entry_t entry, next; vm_object_t object; td = curthread; - while ((entry = td->td_map_def_user) != NULL) { - td->td_map_def_user = entry->next; + entry = td->td_map_def_user; + td->td_map_def_user = NULL; + while (entry != NULL) { + next = entry->next; if ((entry->eflags & MAP_ENTRY_VN_WRITECNT) != 0) { /* * Decrement the object's writemappings and @@ -494,6 +496,7 @@ vm_map_process_deferred(void) entry->end); } vm_map_entry_deallocate(entry, FALSE); + entry = next; } }