Hi Weiwen, On Tue, Jan 19, 2021 at 02:02:56PM +0800, 胡玮文 wrote: > Hi Xiang, > > After further investgate, this bug will not reveal in any released version of > mkfs.erofs. Previous patch v5 [1] will map all allocated bb when erofs_mapbh() > is called on an already mapped bb, which triggers this bug. before that patch, > under the same condition, __erofs_battach() will only be called on bb which is > not mapped, thus no need to update `tail_blkaddr'.
Good to know this, thanks! I haven't looked into that (I will test it this weekend.) IMO, although this is not a regression, yet it seems it's potential harmful if we didn't notice this... So I think a proper testcase is still useful to look after this... If you have extra time, could you help on it? Also, without the detail of this, I think the fix might be folded into the original patchset (could you resend it?). In addition, I think after last_mapped_block is introduced, we might not need tail_blkaddr anymore, not sure. But I'm very cautious about this in case of introducing any new regression... Thanks, Gao Xiang > > [1]: > https://lore.kernel.org/linux-erofs/[email protected]/ > > Hu Weiwen >
