On Thu 17-01-13 13:35:01, Ted Tso wrote: > On Wed, Jan 02, 2013 at 06:45:41PM +0100, Jan Kara wrote: > > When we cannot write a page we should use redirty_page_for_writepage() > > instead of plain set_page_dirty(). That tells writeback code we have > > problems, redirties only the page (redirtying buffers is not needed), > > and updates mm accounting of failed page writes. > > > > Also move clearing of buffer dirty flag after io_submit_add_bh(). At that > > moment we are sure buffer will be going to disk. > > > > Signed-off-by: Jan Kara <jack@xxxxxxx> > > This sounds like a bug fix, not just a clean up. Do you think the Yes, it's a bug fix. > impact of not using redirty_page_for_writeback() is bad enough that we > should add a cc: stable@xxxxxxxxxxxxxxx tag? As I recall, not doing > this would end up leaving the page flags and radix tree to be > inconsistent, right? No, it shouldn't cause any such serious harm. Just writeback may retry writing the inode immediately (it backs off if it sees skipped pages) which could result in needless spinning. Also some mm/bdi statistics will get slightly off. But all in all I don't think it's a stable material. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
