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

Access the swap_pagers' ->putpages() through swappagerops instead

2003-08-06 12:05:48 +00:00

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

Zero the physical page only if it is invalid and not prezeroed.

2004-04-25 07:58:59 +00:00

pmap.h

- pmap_kenter_temporary() is unused by machine-independent code. Therefore,

2004-04-10 22:41:46 +00:00

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

Remove advertising clause from University of California Regent's license,

2004-04-06 20:15:37 +00:00

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

* Add a "how" argument to uma_zone constructors and initialization functions

2004-08-02 00:18:36 +00:00

uma_int.h

Rework the way slab header storage space is calculated in UMA.

2004-07-29 15:25:40 +00:00

uma.h

* Add a "how" argument to uma_zone constructors and initialization functions

2004-08-02 00:18:36 +00:00

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

Remove dead code. A vm_map's first_free is never NULL (even if the map is

2004-08-07 05:58:31 +00:00

vm_kern.c

Use VM_ALLOC_NOBUSY instead of calling vm_page_wakeup().

2004-10-24 18:46:32 +00:00

vm_kern.h

Remove advertising clause from University of California Regent's license,

2004-04-06 20:15:37 +00:00

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

Replace the linear search in vm_map_findspace() with an O(log n)

2004-08-13 08:06:34 +00:00

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

Remove references to L1 in the comments, according to Alan they are

2004-06-07 19:33:05 +00:00

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

Remove advertising clause from University of California Regent's license,

2004-04-06 20:15:37 +00:00

vm_zeroidle.c

Remove dangling variable

2004-11-06 11:33:11 +00:00

vm.h

- Introduce and use a new tunable "debug.mpsafevm". At present, setting

2004-08-16 06:16:12 +00:00

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

Remove advertising clause from University of California Regent's license,

2004-04-06 20:15:37 +00:00