delphij 2841d31dff Try to close a potential, but serious race in our VM subsystem. ... Historically, our contigmalloc1() and contigmalloc2() assumes that a page in PQ_CACHE can be unconditionally reused by busying and freeing it. Unfortunatelly, when object happens to be not NULL, the code will set m->object to NULL and disregard the fact that the page is actually in the VM page bucket, resulting in page bucket hash table corruption and finally, a filesystem corruption, or a 'page not in hash' panic. This commit has borrowed the idea taken from DragonFlyBSD's fix to the VM fix by Matthew Dillon[1]. This version of patch will do the following checks: - When scanning pages in PQ_CACHE, check hold_count and skip over pages that are held temporarily. - For pages in PQ_CACHE and selected as candidate of being freed, check if it is busy at that time. Note: It seems that this is might be unrelated to kern/72539. Obtained from: DragonFlyBSD, sys/vm/vm_contig.c,v 1.11 and 1.12 [1] Reminded by: Matt Dillon Reworked by: alc MFC After: 1 week		2004-11-24 18:56:13 +00:00
..
default_pager.c
device_pager.c	Use dev_re[fl]thread() to maintain a ref on the device driver while	2004-09-24 05:59:11 +00:00
phys_pager.c
pmap.h
swap_pager.c	Disable U area swapping and remove the routines that create, destroy,	2004-11-20 02:29:00 +00:00
swap_pager.h
uma_core.c	Abstract the logic to look up the uma_bucket_zone given a desired	2004-11-06 11:43:30 +00:00
uma_dbg.c	Fix critical stability problems that can cause UMA mbuf cluster	2004-10-08 20:19:29 +00:00
uma_dbg.h
uma_int.h
uma.h
vm_contig.c	Try to close a potential, but serious race in our VM subsystem.	2004-11-24 18:56:13 +00:00
vm_extern.h	Disable U area swapping and remove the routines that create, destroy,	2004-11-20 02:29:00 +00:00
vm_fault.c	Remove unnecessary check for curthread == NULL.	2004-10-17 20:29:28 +00:00
vm_glue.c	Disable U area swapping and remove the routines that create, destroy,	2004-11-20 02:29:00 +00:00
vm_init.c
vm_kern.c	Use VM_ALLOC_NOBUSY instead of calling vm_page_wakeup().	2004-10-24 18:46:32 +00:00
vm_kern.h
vm_map.c	Push Giant deep into vm_forkproc(), acquiring it only if the process has	2004-09-03 05:11:32 +00:00
vm_map.h
vm_meter.c	Put on my peril sensitive sunglasses and add a flags field to the internal	2004-10-11 22:04:16 +00:00
vm_mmap.c	Don't clear flags we just checked were not set.	2004-10-26 05:57:29 +00:00
vm_object.c	Eliminate an unnecessary atomic operation. Articulate the rationale in	2004-11-06 21:48:45 +00:00
vm_object.h	Move a call to wakeup() from vm_object_terminate() to vnode_pager_dealloc()	2004-11-06 05:33:02 +00:00
vm_page.c	The synchronization provided by vm object locking has eliminated the	2004-11-03 20:17:31 +00:00
vm_page.h	Introduce VM_ALLOC_NOBUSY, an option to vm_page_alloc() and vm_page_grab()	2004-10-24 06:15:36 +00:00
vm_pageout.c	During traversal of the inactive queue, try locking the page's containing	2004-11-05 06:24:05 +00:00
vm_pageout.h	Disable U area swapping and remove the routines that create, destroy,	2004-11-20 02:29:00 +00:00
vm_pageq.c
vm_pager.c	Add pbgetbo()/pbrelbo() lighter weight versions of pbgetvp()/pbrelvp().	2004-11-15 08:47:18 +00:00
vm_pager.h	Improve readability with a bunch of typedefs for the pager ops.	2004-11-09 13:43:20 +00:00
vm_param.h	#include <vm/vm_param.h> instead of <machine/vmparam.h> (the former	2004-11-08 18:20:02 +00:00
vm_unix.c
vm_zeroidle.c	Remove dangling variable	2004-11-06 11:33:11 +00:00
vm.h
vnode_pager.c	Make VOP_BMAP return a struct bufobj for the underlying storage device	2004-11-15 09:18:27 +00:00
vnode_pager.h