3.7-rc2 regression : file copied to CIFS-mounted directory corrupted

[Jongman Heo]

Hi, all,

With 3.7-rc2, I noticed that file copied to CIFS-mounted directory is corrupted. 
Integrity is checked by md5sum.

  1. get md5sum of file located on local (ext4) disk
  2. copy the file to CIFS-mounted directory
  3. check md5sum of the copied file

Host   : Windows 7
Guest : Fedora 16 on VMWare
Kernel : 3.7-rc2

Shared directory exists on Windows 7 Host, and Linux Guest on VMware mounts it using CIFS.

I thought it was related to CIFS or VFS changes, but it wasn't.

Below is a git bisect log, and first bad commit is 5640f768, "net: use a per task frag allocator".

Reverting the commit 5640f768 fixes the corruption issue on CIFS directory.
During revert, I got conflict in net/ipv4/raw.c. I took "parent of 5640f76" hunk to resolve it.

# git bisect log
git bisect start
# bad: [6f0c0580b70c89094b3422ba81118c7b959c7556] Linux 3.7-rc2
git bisect bad 6f0c0580b70c89094b3422ba81118c7b959c7556
# good: [a0d271cbfed1dd50278c6b06bead3d00ba0a88f9] Linux 3.6
git bisect good a0d271cbfed1dd50278c6b06bead3d00ba0a88f9
# good: [fec344e3f31aa911297cd3a4639432d983b1f324] cifs: change cifs_call_async to use smb_rqst structs
git bisect good fec344e3f31aa911297cd3a4639432d983b1f324
# good: [3d6d854a13844223b603fd7a16a4a4a4afd62c72] cifs: add FL_CLOSE to fl_flags mask in cifs_read_flock
git bisect good 3d6d854a13844223b603fd7a16a4a4a4afd62c72
# good: [f065fd099fc475333fc7a55677a7f64764445d55] CIFS: Fix possible freed pointer dereference in CIFS_SessSetup
git bisect good f065fd099fc475333fc7a55677a7f64764445d55
# bad: [b7a10626c8bc88fd097a8bb4486c89558f89320c] [CIFS] WARN_ON_ONCE if kernel_sendmsg() returns -ENOSPC
git bisect bad b7a10626c8bc88fd097a8bb4486c89558f89320c
# good: [1d4ab9077681b7cce60ff46e3a42fe2dafa0b83d] [CIFS] Fix indentation of fs/cifs/Kconfig entries
git bisect good 1d4ab9077681b7cce60ff46e3a42fe2dafa0b83d
# bad: [aab174f0df5d72d31caccf281af5f614fa254578] Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
git bisect bad aab174f0df5d72d31caccf281af5f614fa254578
# good: [d9a807461fc8cc0d6ba589ea0730d139122af012] Merge tag 'usb-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
git bisect good d9a807461fc8cc0d6ba589ea0730d139122af012
# good: [a20acf99f75e49271381d65db097c9763060a1e8] Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next
git bisect good a20acf99f75e49271381d65db097c9763060a1e8
# bad: [d379142bc4d9b78cdd9fc5aa696ca1ea083fb7d4] be2net: fixup log messages
git bisect bad d379142bc4d9b78cdd9fc5aa696ca1ea083fb7d4
# good: [2a35cfa591ac63f17815c2d9432b799e37527980] r8169: add D-Link DGE-560T identifiers.
git bisect good 2a35cfa591ac63f17815c2d9432b799e37527980
# good: [9316f0e3c6ba524d8fa14bfded048b252891931a] Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem
git bisect good 9316f0e3c6ba524d8fa14bfded048b252891931a
# good: [623df484a777f3c00c1ea3d6a7565b8d8ac688a1] tcp: extract code to compute SYNACK RTT
git bisect good 623df484a777f3c00c1ea3d6a7565b8d8ac688a1
# bad: [c523530ce17defe6b28ccfe622c506488f430866] can: c_can: fix segfault during rmmod
git bisect bad c523530ce17defe6b28ccfe622c506488f430866
# good: [6ee584be3ee30f72dec8a8ca87bc10824e27a631] netfilter: nfnetlink_queue: add NFQA_CAP_LEN attribute
git bisect good 6ee584be3ee30f72dec8a8ca87bc10824e27a631
# good: [725b9c0425f54450d1f376befb85dae706ea0c7a] qeth: cleanup channel path descriptor function
git bisect good 725b9c0425f54450d1f376befb85dae706ea0c7a
# good: [0cf833aefaa85bbfce3ff70485e5534e09254773] net: loopback: set default mtu to 64K
git bisect good 0cf833aefaa85bbfce3ff70485e5534e09254773
# bad: [9e49e88958feb41ec701fa34b44723dabadbc28c] filter: add XOR instruction for use with X/K
git bisect bad 9e49e88958feb41ec701fa34b44723dabadbc28c
# bad: [5640f7685831e088fe6c2e1f863a6805962f8e81] net: use a per task frag allocator
git bisect bad 5640f7685831e088fe6c2e1f863a6805962f8e81
# good: [b98b8babd6e3370fadb7c6eaacb00eb2f6344a6c] gianfar: Change default HW Tx queue scheduling mode
git bisect good b98b8babd6e3370fadb7c6eaacb00eb2f6344a6c
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