On 3/30/12 5:57 AM, Richard W.M. Jones wrote: > [I'm tracking this issue here: > https://bugzilla.redhat.com/show_bug.cgi?id=808421] > > febootstrap uses the ext2fs library to construct an ext2 filesystem. > > Since we updated to the latest version in git, febootstrap segfaults > in ext2fs_find_first_zero_generic_bmap (called from ext2fs_new_inode). > There's a complete stack trace in the bug above. > > I'm not claiming that we are calling this library correctly, but, > you know, "it always worked until now". Sami, can you take a look at this one? It seems that your commit does not handle 32-bit bitmaps. Thanks, -Eric > Here is the calling code: > > https://github.com/libguestfs/febootstrap/blob/636a80b5a70382f21da47c44a0acd3efa2bc7fcf/helper/ext2.c#L142 > > git bisect points to this change being the one which causes the > problem: > > c1a1e7fc24d6e37f931bbb8eeb29c90243f0a55d is the first bad commit > commit c1a1e7fc24d6e37f931bbb8eeb29c90243f0a55d > Author: Sami Liedes <sami.liedes@xxxxxx> > Date: Sat Mar 10 22:36:12 2012 +0200 > > libext2fs: Implement ext2fs_find_first_zero_generic_bmap(). > > This function searches a bitmap for the first zero bit within a range. > It checks if there is a bitmap backend specific implementation > available (if the relevant field in bitmap_ops is non-NULL). If not, > it uses a generic and slow method by repeatedly calling test_bmap() in > a loop. Also change ext2fs_new_inode() to use this new function. > > This change in itself does not result in a large speedup, rather it > refactors the code in preparation for the introduction of a faster > find_first_zero() for bitarray based bitmaps. > > Signed-off-by: Sami Liedes <sami.liedes@xxxxxx> > Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> > > Rich. > -- 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
