On Thursday May 17, neilb@xxxxxxx wrote: > > Uhm, I just noticed something. > 'chunk' is unsigned long, and when it gets shifted up, we might lose > bits. That could still happen with the 4*2.75T arrangement, but is > much more likely in the 2*5.5T arrangement. Actually, it cannot be a problem with the 4*2.75T arrangement. chuck << chunksize_bits will not exceed the size of the underlying device *in*kilobytes*. In that case that is 0xAE9EC800 which will git in a 32bit long. We don't double it to make sectors until after we add zone->dev_offset, which is "sector_t" and so 64bit arithmetic is used. So I'm quite certain this bug will cause exactly the problems experienced!! > > Jeff, can you try this patch? Don't bother about the other tests I mentioned, just try this one. Thanks. NeilBrown > Signed-off-by: Neil Brown <neilb@xxxxxxx> > > ### Diffstat output > ./drivers/md/raid0.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff .prev/drivers/md/raid0.c ./drivers/md/raid0.c > --- .prev/drivers/md/raid0.c 2007-05-17 10:33:30.000000000 +1000 > +++ ./drivers/md/raid0.c 2007-05-17 15:02:15.000000000 +1000 > @@ -475,7 +475,7 @@ static int raid0_make_request (request_q > x = block >> chunksize_bits; > tmp_dev = zone->dev[sector_div(x, zone->nb_dev)]; > } > - rsect = (((chunk << chunksize_bits) + zone->dev_offset)<<1) > + rsect = ((((sector_t)chunk << chunksize_bits) + zone->dev_offset)<<1) > + sect_in_chunk; > > bio->bi_bdev = tmp_dev->bdev; - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
