On 08/03, Chao Yu wrote: > On 2021/8/3 1:59, Jaegeuk Kim wrote: > > On 08/01, Chao Yu wrote: > > > On 2021/7/31 6:18, Jaegeuk Kim wrote: > > > > On 07/20, Chao Yu wrote: > > > > > On 2021/7/20 2:25, Jaegeuk Kim wrote: > > > > > > On 07/19, Chao Yu wrote: > > > > > > > On 2021/4/27 20:37, Chao Yu wrote: > > > > > > > > I think just reverting dirty/free bitmap is not enough if > > > > > > > > checkpoint fails, > > > > > > > > due to we have updated sbi->cur_cp_pack and nat/sit bitmap, > > > > > > > > next CP tries > > > > > > > > to overwrite last valid meta/node/data, then filesystem will be > > > > > > > > corrupted. > > > > > > > > > > > > > > > > So I suggest to set cp_error if do_checkpoint() fails until we > > > > > > > > can handle > > > > > > > > all cases, which is not so easy. > > > > > > > > > > > > > > > > How do you think? > > > > > > > > > > > > > > Let's add below patch first before you figure out the patch which > > > > > > > covers all > > > > > > > things. > > > > > > > > > > > > > > From 3af957c98e9e04259f8bb93ca0b74ba164f3f27e Mon Sep 17 > > > > > > > 00:00:00 2001 > > > > > > > From: Chao Yu <[email protected]> > > > > > > > Date: Mon, 19 Jul 2021 16:37:44 +0800 > > > > > > > Subject: [PATCH] f2fs: fix to stop filesystem update once CP > > > > > > > failed > > > > > > > > > > > > > > During f2fs_write_checkpoint(), once we failed in > > > > > > > f2fs_flush_nat_entries() or do_checkpoint(), metadata of > > > > > > > filesystem > > > > > > > such as prefree bitmap, nat/sit version bitmap won't be recovered, > > > > > > > it may cause f2fs image to be inconsistent, let's just set CP > > > > > > > error > > > > > > > flag to avoid further updates until we figure out a scheme to > > > > > > > rollback > > > > > > > all metadatas in such condition. > > > > > > > > > > > > > > Reported-by: Yangtao Li <[email protected]> > > > > > > > Signed-off-by: Yangtao Li <[email protected]> > > > > > > > Signed-off-by: Chao Yu <[email protected]> > > > > > > > --- > > > > > > > fs/f2fs/checkpoint.c | 10 +++++++--- > > > > > > > 1 file changed, 7 insertions(+), 3 deletions(-) > > > > > > > > > > > > > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > > > > > > > index 6c208108d69c..096c85022f62 100644 > > > > > > > --- a/fs/f2fs/checkpoint.c > > > > > > > +++ b/fs/f2fs/checkpoint.c > > > > > > > @@ -1639,8 +1639,10 @@ int f2fs_write_checkpoint(struct > > > > > > > f2fs_sb_info *sbi, struct cp_control *cpc) > > > > > > > > > > > > > > /* write cached NAT/SIT entries to NAT/SIT area */ > > > > > > > err = f2fs_flush_nat_entries(sbi, cpc); > > > > > > > - if (err) > > > > > > > + if (err) { > > > > > > > + f2fs_stop_checkpoint(sbi, false); > > > > > > > > > > > > I think we should abuse this, since we can get any known ENOMEM as > > > > > > well. > > > > > > > > > > Yup, but one critical issue here is it can break A/B update of NAT > > > > > area, > > > > > so, in order to fix this hole, how about using NOFAIL memory > > > > > allocation > > > > > in f2fs_flush_nat_entries() first until we figure out the finial > > > > > scheme? > > > > > > > > NOFAIL is risky, so how about adding a retry logic on ENOMEM with a > > > > message > > > > and then giving up if we can't get the memory? BTW, what about EIO or > > > > other > > > > family? > > > > > > How about this? > > > > Hmm, it seems we won't get ENOMEM. > > > > __flush_nat_entry_set > > -> get_next_nat_page > > -> ... > > -> __get_meta_page > > -> repeat on ENOMEM, but stop_checkpoint on EIO > > Correct, I missed to check __get_meta_page() and f2fs_get_meta_page_retry(). > > > > > If we have an error here, we should have stopped checkpoint. Have you seen > > other > > issue? > > Still we should fix the case from below path? > > - f2fs_write_checkpoint > - do_checkpoint > - f2fs_flush_device_cache failed
What about adding a retry logic to deal with EIO in __submit_flush_wait()? We probably need to retry submitting FLUSH commands, and then give up with f2fs_stop_checkpoint(). And, then how about adding f2fs_bug_on() if f2fs_flush_nat_entries() returns error without f2fs_cp_error()? > > Thanks, _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
