Wolfgang Breyha wrote on 09/09/16 00:26: > On 08/09/16 17:47, David Laight wrote: >> Try writing with: >> dd if=768MB.test of=/dev/sdb oflag=direct bs=1M seek_bytes seek=$((n*512)) >> for several small values of 'n' so that the writes are misaligned. >> >> It may also be worth finding out what the USB transfers look like. > > I was wrong when I wrote that the stick fails on 4.7.2 as well. I confused > it with the last 4.6.7 update for Fedora. And I found the difference. 4.7.2 > uses max_sectors 2048 with this stick and this seems to work flawlessly. > 4.6.x used 240. If I set max_sectors to 2048 on 4.6.x it works as well. So > at least my unusual_devs addition seems obsolete (at least for 4.7.x) I updated the last missing systems to 4.7.2 (most recent Fedora 24 release) as well and the stick failed with max_sectors 2048 today, too. It seems to happen not that often, but file corruption is still there. Combined with direct IO it seemed to work. Since reading with different offsets leads to different errors I already reported I'm unsure how to help to find the root cause. Setting max_sectors to 64 seems the only way to prevent file corruption for now. With kind regards, Wolfgang Breyha -- Wolfgang Breyha <wbreyha@xxxxxxx> | http://www.blafasel.at/ Vienna University Computer Center | Austria -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
