From 0f75a9772201e545f3540f780a3cbc6c241cb014 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Thu, 19 Feb 2004 07:43:55 +0000 Subject: - Correct a long-standing race condition in vm_page_try_to_free() that could result in a dirty page being unintentionally freed. - Simplify the dirty page check in vm_page_dontneed(). Reviewed by: tegge MFC after: 7 days --- sys/vm/vm_page.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'sys') diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c index 9bc15feabb4b..853178aa4630 100644 --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -1316,11 +1316,10 @@ vm_page_try_to_free(vm_page_t m) (m->flags & (PG_BUSY|PG_UNMANAGED))) { return (0); } - vm_page_test_dirty(m); + pmap_remove_all(m); if (m->dirty) return (0); vm_page_busy(m); - pmap_remove_all(m); vm_page_free(m); return (1); } @@ -1405,8 +1404,8 @@ vm_page_dontneed(vm_page_t m) return; } - if (m->dirty == 0) - vm_page_test_dirty(m); + if (m->dirty == 0 && pmap_is_modified(m)) + vm_page_dirty(m); if (m->dirty || (dnw & 0x0070) == 0) { /* -- cgit v1.3