vm_page_free_invalid(): Relax the xbusy assertion.

vm_page_assert_xbusied() asserts that the busying thread is the current
thread.  For some uses of vm_page_free_invalid() (e.g., error handling
in vnode_pager_generic_getpages_done()), this condition might not hold.

Reported by:	Jenkins via trasz
Reviewed by:	chs, kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D25828
This commit is contained in:
Mark Johnston 2020-07-27 14:25:10 +00:00
parent 58f5de0d8a
commit 782ebde52e

View File

@ -1371,10 +1371,15 @@ vm_page_free_invalid(vm_page_t m)
KASSERT(vm_page_none_valid(m), ("page %p is valid", m));
KASSERT(!pmap_page_is_mapped(m), ("page %p is mapped", m));
vm_page_assert_xbusied(m);
KASSERT(m->object != NULL, ("page %p has no object", m));
VM_OBJECT_ASSERT_WLOCKED(m->object);
/*
* We may be attempting to free the page as part of the handling for an
* I/O error, in which case the page was xbusied by a different thread.
*/
vm_page_xbusy_claim(m);
/*
* If someone has wired this page while the object lock
* was not held, then the thread that unwires is responsible