From: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
[ Upstream commit fb8bc4c74ae4526d9489362ab2793a936d072b84 ]
There are two states for ubifs writing pages:
1. Dirty, Private
2. Not Dirty, Not Private
There is a third possibility which maybe related to [1] that page is
private but not dirty caused by following process:
PA
lock(page)
ubifs_write_end
attach_page_private // set Private
__set_page_dirty_nobuffers // set Dirty
unlock(page)
write_cache_pages
lock(page)
clear_page_dirty_for_io(page) // clear Dirty
ubifs_writepage
write_inode
// fail, goto out, following codes are not executed
// do_writepage
// set_page_writeback // set Writeback
// detach_page_private // clear Private
// end_page_writeback // clear Writeback
out:
unlock(page) // Private, Not Dirty
PB
ksys_fadvise64_64
generic_fadvise
invalidate_inode_page
// page is neither Dirty nor Writeback
invalidate_complete_page
// page_has_private is true
try_to_release_page
ubifs_releasepage
ubifs_assert(c, 0) !!!
Then we may get following assertion failed:
UBIFS error (ubi0:0 pid 1492): ubifs_assert_failed [ubifs]:
UBIFS assert failed: 0, in fs/ubifs/file.c:1499
UBIFS warning (ubi0:0 pid 1492): ubifs_ro_mode [ubifs]:
switched to read-only mode, error -22
CPU: 2 PID: 1492 Comm: aa Not tainted 5.16.0-rc2-00012-g7bb767dee0ba-dirty
Call Trace:
dump_stack+0x13/0x1b
ubifs_ro_mode+0x54/0x60 [ubifs]
ubifs_assert_failed+0x4b/0x80 [ubifs]
ubifs_releasepage+0x7e/0x1e0 [ubifs]
try_to_release_page+0x57/0xe0
invalidate_inode_page+0xfb/0x130
invalidate_mapping_pagevec+0x12/0x20
generic_fadvise+0x303/0x3c0
vfs_fadvise+0x35/0x40
ksys_fadvise64_64+0x4c/0xb0
Jump [2] to find a reproducer.
[1] https://linux-mtd.infradead.narkive.com/NQoBeT1u/patch-rfc-ubifs-fix-assert-failed-in-ubifs-set-page-dirty
[2] https://bugzilla.kernel.org/show_bug.cgi?id=215357
Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
Signed-off-by: Richard Weinberger <richard@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ubifs/file.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 354457e846cda..19fdcda045890 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1031,7 +1031,7 @@ static int ubifs_writepage(struct page *page, struct writeback_control *wbc)
if (page->index >= synced_i_size >> PAGE_SHIFT) {
err = inode->i_sb->s_op->write_inode(inode, NULL);
if (err)
- goto out_unlock;
+ goto out_redirty;
/*
* The inode has been written, but the write-buffer has
* not been synchronized, so in case of an unclean
@@ -1059,11 +1059,17 @@ static int ubifs_writepage(struct page *page, struct writeback_control *wbc)
if (i_size > synced_i_size) {
err = inode->i_sb->s_op->write_inode(inode, NULL);
if (err)
- goto out_unlock;
+ goto out_redirty;
}
return do_writepage(page, len);
-
+out_redirty:
+ /*
+ * redirty_page_for_writepage() won't call ubifs_dirty_inode() because
+ * it passes I_DIRTY_PAGES flag while calling __mark_inode_dirty(), so
+ * there is no need to do space budget for dirty inode.
+ */
+ redirty_page_for_writepage(wbc, page);
out_unlock:
unlock_page(page);
return err;
--
2.39.2
