On Fri, Oct 10, 2008 at 06:02:09PM +0900, Hidehiro Kawai wrote: > Currently, original metadata buffers are dirtied when they are > unfiled whether the journal has aborted or not. Eventually these > buffers will be written-back to the filesystem by pdflush. This > means some metadata buffers are written to the filesystem without > journaling if the journal aborts. So if both journal abort and > system crash happen at the same time, the filesystem would become > inconsistent state. Additionally, replaying journaled metadata > can overwrite the latest metadata on the filesystem partly. > Because, if the journal gets aborted, journaled metadata are > preserved and replayed during the next mount not to lose > uncheckpointed metadata. This would also break the consistency > of the filesystem. > > This patch prevents original metadata buffers from being dirtied > on abort by clearing BH_JBDDirty flag from those buffers. Thus, > no metadata buffers are written to the filesystem without journaling. It's not my place to Ack such patches, but I noticed this bug during Plumbers, and Eric and Andreas pointed me to this patch, which fixes it quite nicely. Just $0.02 :-) Joel -- Life's Little Instruction Book #94 "Make it a habit to do nice things for people who will never find out." Joel Becker Principal Software Developer Oracle E-mail: joel.becker@xxxxxxxxxx Phone: (650) 506-8127 -- 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
