github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-11 20:13:02 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

libceph: remove pinning assertion in ceph_msg_data_iter_next()

Browse Source 
ceph_msg_data_iter_next() gets a page reference from
iov_iter_get_pages2() only to immediately drop it, asserting that the
page is pinned some other way. The assertion is the last caller of
PageWriteback() in the tree, blocking removal of the PG_writeback page
flag accessors.

Remove the assertion, as it is a CONFIG_DEBUG_VM-only check of an
assumption the FIXME comment already documents. Converting to
iov_iter_extract_pages() instead was considered, but the messenger never
releases what it extracts, so it would still rely entirely on the caller
holding the pages. That would be just as much of an abuse of the API, so
leave it as-is for now.

Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Tal Zussman 2026-08-25 11:41:38 -04:00 committed by Ilya Dryomov
parent a61c6ae1da
commit f75987e543
1 changed files with 0 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
net/ceph/messenger.c
View File

@ -1003,7 +1003,6 @@ static struct page *ceph_msg_data_iter_next(struct ceph_msg_data_cursor *cursor,
* we'll get an iov_iter_get_pages2 variant that doesn't take
* page refs. Until then, just put the page ref.
*/
VM_BUG_ON_PAGE(!PageWriteback(page) && page_count(page) < 2, page);
put_page(page);
*length = min_t(size_t, len, cursor->resid);