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| author | alc <alc@FreeBSD.org> | 2008-01-02 04:43:47 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 2008-01-02 04:43:47 +0000 |
| commit | 3c35e9380cd7de2ebe4957d7e90864e376bb73b8 (patch) | |
| tree | 38bc50877391eaf9dd285534bf3d3543e46be8ce /sys/vm | |
| parent | 0ba0d86d89efcaaea861a659c5b68e746e803d21 (diff) | |
| download | FreeBSD-src-3c35e9380cd7de2ebe4957d7e90864e376bb73b8.zip FreeBSD-src-3c35e9380cd7de2ebe4957d7e90864e376bb73b8.tar.gz | |
Defer setting either PG_CACHED or PG_FREE until after the free page
queues lock is acquired. Otherwise, the state of a reservation's
pages' flags and its population count can be inconsistent. That could
result in a page being freed twice.
Reported by: kris
Diffstat (limited to 'sys/vm')
| -rw-r--r-- | sys/vm/vm_page.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c index 485b738..cea7a23 100644 --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -1332,8 +1332,8 @@ vm_page_free_toq(vm_page_t m) m->flags &= ~PG_ZERO; vm_pageq_enqueue(PQ_HOLD, m); } else { - m->flags |= PG_FREE; mtx_lock(&vm_page_queue_free_mtx); + m->flags |= PG_FREE; cnt.v_free_count++; #if VM_NRESERVLEVEL > 0 if (!vm_reserv_free_page(m)) @@ -1584,9 +1584,9 @@ vm_page_cache(vm_page_t m) * Insert the page into the object's collection of cached pages * and the physical memory allocator's cache/free page queues. */ - vm_page_flag_set(m, PG_CACHED); vm_page_flag_clear(m, PG_ZERO); mtx_lock(&vm_page_queue_free_mtx); + m->flags |= PG_CACHED; cnt.v_cache_count++; root = object->cache; if (root == NULL) { |
