Peng Tao wrote: > Hi, Akira, > > 2009/8/3 Akira Fujita <a-fujita@xxxxxxxxxxxxx>: >> Hi Peng, >> >> Peng Tao wrote: >>> move_extent_par_page calls a_ops->write_begin() to increase journal handler's >>> reference count. However, if either mext_replace_branches() or ext4_get_block >>> fails, the increased reference count isn't decreased. This will cause later >>> umounting of the fs forever hangs. The patch addresses the issue by calling >>> ext4_journal_stop() if page is not NULL (which means a_ops->write_end() isn't >>> invoked). >> In case mext_replaced_branches() or ext4_get_block failed, >> ext4_journal_stop() is called at out2 label(*) >> and then journal reference counter is decreased. >> Therefore I think this fix is not necessary. > well, the orginal code calls both ext4_journal_start and > a_ops->write_begin(). So the journal reference was increased twice but > only gets decreased once in case of failure. This can be simply > verified by returning -1 at the begining of mext_replaced_branches(). > With such modification, the fs cannot be umounted because of the wrong > reference count. Ah, I missed. Sorry for the noise. The patch looks good to me. Regards, Akira Fujita -- 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
