On Wednesday 18 March 2009 04:33:55 Jan Kara wrote: > Make submit_bh() warn about writing !uptodate buffers. Hopefully this > warns us about writing garbage (although bugs in write EIO handling > are going to trigger this as well as they already trigger the warning > in mark_buffer_dirty()). > > Signed-off-by: Jan Kara <jack@xxxxxxx> > --- > fs/buffer.c | 2 ++ > 1 files changed, 2 insertions(+), 0 deletions(-) > > diff --git a/fs/buffer.c b/fs/buffer.c > index 22c0144..985f617 100644 > --- a/fs/buffer.c > +++ b/fs/buffer.c > @@ -2997,6 +2997,8 @@ int submit_bh(int rw, struct buffer_head * bh) > BUG_ON(!buffer_locked(bh)); > BUG_ON(!buffer_mapped(bh)); > BUG_ON(!bh->b_end_io); > + if (rw & WRITE) > + WARN_ON_ONCE(!buffer_uptodate(bh)); Yes very nice assertion to have. Arguably I think it should be a BUG_ON because it is definitely some state corruption at least, and writing garbage data to disk at worst. But WARN_ON for now is probably best. I have some patches to fix up some problems with EIO handling in the VM (and I think solves the the buffer warning too). I have to get them out and try to get them merged again... at which point this should probably be turned into a bug. Acked-by: Nick Piggin <npiggin@xxxxxxx> -- 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
