Evan Felix <evan.felix@pnl.gov> writes: > Here is a patch that fixes a major issue in the raid5/6 code. It seems > that the code: > > logical_sector = bi->bi_sector & ~(STRIPE_SECTORS-1); > (sector_t) = (sector_t) & (constant) > > that the right side of the & does not get extended correctly when the > constant is promoted to the sector_t type. I have CONFIG_LBD turned on > so sector_t should be 64bits wide. This fails to properly mask the > value of 4294967296 (2TB/512) to 4294967296. in my case it was coming > out 0. this cause the loop following this code to read from 0 to > 4294967296 blocks so it could write one character. > > As you might imagine this makes a format of a 3.5TB filesystem take a > very long time. > > Here is the patch: Alternatively replace ~(STRIPE_SECTORS-1) by -STRIPE_SECTORS, which doesn't need a cast. Andreas. -- Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux AG, Maxfeldstraße 5, 90409 Nürnberg, Germany Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different." - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
