On Wed, Feb 25, 2009 at 03:39:52PM +0900, Kazuya Mio wrote: > Hi Aneesh, > > When I remove the file that is running online defrag, the following error occurs > after closing the file descriptor: > > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): > ext4_mb_release_inode_pa: free 2048, pa_free 1562 > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802817(bit 0 in group 98) > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802818(bit 1 in group 98) > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802819(bit 2 in group 98) > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802820(bit 3 in group 98) > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802821(bit 4 in group 98) > Jan 22 17:06:52 G3-OPC-SVR2 kernel: EXT4-fs error (device hda8): mb_free_blocks: > double-free of inode 0's block 802822(bit 5 in group 98) > > So, online defrag calls ext4_discard_preallocations() at the end of > ext4_defrag() to avoid double-free error. > However, above error hasn't occurred since applying your patch posted on Nov > 6th, 2008 because this error is caused by the same reason of your report. > http://marc.info/?l=linux-ext4&m=122599787406193&w=4 > > What is the status of this patch? We dropped the patch because I found that the double free in my case was not exactly due the explanation given in the patch above. I asked to drop the patch in http://article.gmane.org/gmane.comp.file-systems.ext4/10199 I also found that the patch is not completely correct. The meta-data blocks which are added to the free_list are not allocated from any prealloc space. So what you are seeing may be a different problem which the patch is hiding from happening. I guess you will have to look more closely at why the double-free is happening in your case. -aneesh -- 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
