2011/10/13 Jeff Layton <jlayton@xxxxxxxxxx>: > On Thu, 13 Oct 2011 16:46:51 +0400 > Pavel Shilovsky <piastryyy@xxxxxxxxx> wrote: > >> 2011/10/13 Jeff Layton <jlayton@xxxxxxxxxx>: >> > On Thu, 13 Oct 2011 11:28:29 +0400 >> > Pavel Shilovsky <piastryyy@xxxxxxxxx> wrote: >> > >> >> I tested your current cifs-3.2 branch and faced with strange results >> >> (assuming Windows 7 share is mounted to /mnt/share): >> >> >> > >> > I've not seen this, but I'll try to reproduce it in a little while. >> > >> >> piastry@adventure:~$ dd if=test1.iso of=/mnt/share/test.iso bs=100000 >> >> >> > >> > Ok, so test1.iso is in your home directory and you're dd'ing it >> > to /mnt/share/test.iso (which is a cifs mount) >> > >> >> piastry@adventure:~$ dd of=test.iso if=/mnt/share/test.iso bs=100000 >> >> >> > >> > Then you copy test.iso back from the share to your homedir >> > >> >> piastry@adventure:~$ md5sum test.iso >> >> 5eee1675f46ac594dd7800c37e3ba944 test.iso >> >> >> > >> > Checksum of test.iso in your homedir and end up with the above... >> > >> >> piastry@adventure:~$ md5sum /mnt/share/test.iso >> >> 5eee1675f46ac594dd7800c37e3ba944 /mnt/HOME-share/test.iso >> >> >> > >> > The checksum matches the (apparent) one on the share >> > >> >> piastry@adventure:~$ md5sum test1.iso >> >> 10d672583cab035e2b55048fbfbbf7ca test1.iso >> >> >> > >> > But does not match the original. >> > >> >> Then, I umounted and mounted it again with 3.1-rc9 cifs module - >> >> everything was fine. Then, I load previous "buggy" one and everything >> >> was fine too. >> >> >> >> So, md5sums are not equal. Any ideas? >> >> >> > >> > Not something I've seen in my testing. Some questions: >> > >> > 1) where is your home directory? is it on a local disk? >> >> It's on ext3 local hard drive. >> >> > >> > 2) when you say "everything was fine" what checksum did you get? >> >> all checksums matched the original. >> >> > >> > 3) if this test is repeatable, is there any discrepancy in the size of >> > the file? IOW, when you do the md5sum, it would be good to also do a >> > "stat" against the file the i_size is coming up correctly after each >> > step. >> >> The size was the same - 415 MB. One time it happened I calculated the >> number of different characters in these files - it was 127 (I don't >> know how it can help, but anyway). >> > > I tried this too, but haven't been able to reproduce it. Grabbed a > random .iso file which is a bit bigger than yours -- 615M, and tried > several of these tests and the checksum always came out the same... > > Do any of the dd commands return an error? > No. It's hard to catch - I faced with it only twice while testing it (for about 30 runs). -- Best regards, Pavel Shilovsky. -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
