freebsd-dev/sys/vm
Brian Feldman d951b75210 Fix a race in vm_page_sleep_if_busy(). Due to vm_object locking
being incomplete, it currently has to know how to drop and pick back
up the vm_object's mutex if it has to sleep and drop the page queue
mutex.  The problem with this is that if the page is busy, while we
are sleeping, the page can be freed and object disappear.  When trying
to lock m->object, we'd get a stale or NULL pointer and crash.

The object is now cached, but this makes the assumption that
the object is referenced in some manner and will not itself
disappear while it is unlocked.  Since this only happens if
the object is locked, I had to remove an assumption earlier in
contigmalloc() that reversed the order of locking the object and
doing vm_page_sleep_if_busy(), not the normal order.
2004-07-21 23:56:09 +00:00
..
default_pager.c
device_pager.c Do the dreaded s/dev_t/struct cdev */ 2004-06-16 09:47:26 +00:00
phys_pager.c
pmap.h
swap_pager.c Properly brucify a string by outdenting it. 2004-07-06 02:27:30 +00:00
swap_pager.h
uma_core.c Since breakage of malloc(9)/uma_zalloc(9) is totally non-optional in 2004-07-19 15:05:24 +00:00
uma_dbg.c
uma_dbg.h
uma_int.h
uma.h Fix a comment above uma_zsecond_create(), describing its arguments. 2004-06-01 01:36:26 +00:00
vm_contig.c Remove extraneous locks on the VM free page queue mutex; it is not 2004-07-19 23:29:36 +00:00
vm_extern.h
vm_fault.c
vm_glue.c - Don't use a variable to point to the user area that we only use once. 2004-07-02 03:45:07 +00:00
vm_init.c
vm_kern.c
vm_kern.h
vm_map.c Semi-gratuitous change. Move two refcount operations to their own lines 2004-07-21 05:08:10 +00:00
vm_map.h Micro-optimize vmspace for 64-bit architectures: Colocate vm_refcnt and 2004-07-06 17:35:10 +00:00
vm_meter.c
vm_mmap.c Deorbit COMPAT_SUNOS. 2004-06-11 11:16:26 +00:00
vm_object.c Initialize result->backing_object_offset before linking result onto the list of 2004-06-28 20:26:35 +00:00
vm_object.h
vm_page.c Fix a race in vm_page_sleep_if_busy(). Due to vm_object locking 2004-07-21 23:56:09 +00:00
vm_page.h Reimplement contigmalloc(9) with an algorithm which stands a greatly- 2004-07-19 06:21:27 +00:00
vm_pageout.c Remove the GIANT_REQUIRED preceding pmap_remove() in 2004-07-18 04:38:11 +00:00
vm_pageout.h
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
vm_pager.h
vm_param.h Second half of the dev_t cleanup. 2004-06-17 17:16:53 +00:00
vm_unix.c
vm_zeroidle.c Implement preemption of kernel threads natively in the scheduler rather 2004-07-02 20:21:44 +00:00
vm.h
vnode_pager.c
vnode_pager.h