On Tue, Mar 23, 2010 at 11:34:20AM -0400, Chris Mason wrote: > On Mon, Mar 22, 2010 at 02:31:08AM +0300, Alexander Beregalov wrote: > > Btrfs on Sparc64 produces a lot of warnings > > Kernel unaligned access at TPC[10148c84] btrfs_csum_final+0x44/0x60 [btrfs] > > Great, thanks for trackign this down. > > > > > It happens when btrfs_csum_final is called from write_dev_supers(): > > 2195: btrfs_csum_final(crc, sb->csum); > > > > crc is u32, aligning sb->csum on 4-byte boundary fixes the problem. > > So the size of the csum field is already 4 byte aligned, I'm surprised > we need this? Jens did some testing and this patch changes the size of the super struct, which changes things on disk. But, the real problem is write_dev_supers operates on a copy of the super struct and that copy isn't aligned. So we just need to align the copy in struct btrfs_fs_info, which Jens should have a neat little patch for shortly. So we should finally have this one fixed up shortly. Thanks again. -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
