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| author | attilio <attilio@FreeBSD.org> | 2014-03-19 01:13:42 +0000 |
|---|---|---|
| committer | attilio <attilio@FreeBSD.org> | 2014-03-19 01:13:42 +0000 |
| commit | f19bbde667a9348da3a87d8020cdcdd8e58f77d0 (patch) | |
| tree | 32ddd87329a889e5bd40542e4baf48292475d469 /sys/vm | |
| parent | 060e6c4c4bb0bf187f8d7858b1b57cdbfab83071 (diff) | |
| download | FreeBSD-src-f19bbde667a9348da3a87d8020cdcdd8e58f77d0.zip FreeBSD-src-f19bbde667a9348da3a87d8020cdcdd8e58f77d0.tar.gz | |
vm_page_grab() and vm_pager_get_pages() can drop the vm_object lock,
then threads can sleep on the pip condition.
Avoid to deadlock such threads by correctly awakening the sleeping ones
after the pip is finished.
swapoff side of the bug can likely result in shutdown deadlocks.
Sponsored by: EMC / Isilon Storage Division
Reported by: pho, pluknet
Tested by: pho
Diffstat (limited to 'sys/vm')
| -rw-r--r-- | sys/vm/swap_pager.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c index 54ebf9d..861de94 100644 --- a/sys/vm/swap_pager.c +++ b/sys/vm/swap_pager.c @@ -1713,7 +1713,7 @@ swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex) vm_object_pip_add(object, 1); m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); if (m->valid == VM_PAGE_BITS_ALL) { - vm_object_pip_subtract(object, 1); + vm_object_pip_wakeup(object); vm_page_dirty(m); vm_page_lock(m); vm_page_activate(m); @@ -1725,7 +1725,7 @@ swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex) if (swap_pager_getpages(object, &m, 1, 0) != VM_PAGER_OK) panic("swap_pager_force_pagein: read from swap failed");/*XXX*/ - vm_object_pip_subtract(object, 1); + vm_object_pip_wakeup(object); vm_page_dirty(m); vm_page_lock(m); vm_page_deactivate(m); |
