2.4: crash when unmounting ext2fs

linas@austin.ibm.com
Wed, 16 Apr 2003 12:43:54 -0500


Hi,

I've been chasing a bug in a slightly down-level version of the
kernel (2.4.19) and was wondering if perchance its been fixed
recently ... The crash occurs after a large ext2 filesystem
was heavily used (in a large-memory config), and is then unmounted.
Using KDB, I find myself chasing pointers in discard_bh_page()
(in fs/buffer.c) and one of the bh->b_this_page points at a page
that's clearly been zero'ed, but for one tell-tale clue. It looks
like the zero'ed out page used to be chained correctly into the
lru_list[], and then it was zero'ed out, and then someone called
__remove_from_lru_list() on its neighbor.

I'm a little stumped on how a bh was on the lru_list, got whacked,
and is still in the list of page->buffers that discard_bh_page() is
trying to get rid of. Anyone fix anything like this recently?

Or more generally, any sort of buffer-freeing/page-freeing/file-system
flushing/freeing type bugs where pages might have been zero'ed out
before thier time?

--linas
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/