Doug / smarc-fsl-linux-kernel

22 May, 2010

1 commit

30 Mar, 2010

1 commit

  • 5a0e3ad6a   include cleanup: Update gfp.h and slab.h includes to prepare for breaking implic… ... Browse Code »

    …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

08 Mar, 2010

1 commit

  • 5e31d76f2   Driver-Core: devtmpfs - reset inode permissions before unlinking ... Browse Code »

    Before unlinking the inode, reset the current permissions of possible
    references like hardlinks, so granted permissions can not be retained
    across the device lifetime by creating hardlinks, in the unusual case
    that there is a user-writable directory on the same filesystem.

    Signed-off-by: Kay Sievers
    Cc: stable
    Signed-off-by: Greg Kroah-Hartman

    Kay Sievers
     

21 Jan, 2010

1 commit

  • f776c5ec4   driver-core: fix devtmpfs crash on s390 ... Browse Code »

    On Mon, Jan 18, 2010 at 05:26:20PM +0530, Sachin Sant wrote:
    > Hello Heiko,
    >
    > Today while trying to boot next-20100118 i came across
    > the following Oops :
    >
    > Brought up 4 CPUs
    > Unable to handle kernel pointer dereference at virtual kernel address 0000000000
    > 543000
    > Oops: 0004 #1 SMP
    > Modules linked in:
    > CPU: 0 Not tainted 2.6.33-rc4-autotest-next-20100118-5-default #1
    > Process swapper (pid: 1, task: 00000000fd792038, ksp: 00000000fd797a30)
    > Krnl PSW : 0704200180000000 00000000001eb0b8 (shmem_parse_options+0xc0/0x328)
    > R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
    > Krnl GPRS: 000000000054388a 000000000000003d 0000000000543836 000000000000003d
    > 0000000000000000 0000000000483f28 0000000000536112 00000000fd797d00
    > 00000000fd4ba100 0000000000000100 0000000000483978 0000000000543832
    > 0000000000000000 0000000000465958 00000000001eb0b0 00000000fd797c58
    > Krnl Code: 00000000001eb0aa: c0e5000994f1 brasl %r14,31da8c
    > 00000000001eb0b0: b9020022 ltgr %r2,%r2
    > 00000000001eb0b4: a784010b brc 8,1eb2ca
    > >00000000001eb0b8: 92002000 mvi 0(%r2),0
    > 00000000001eb0bc: a7080000 lhi %r0,0
    > 00000000001eb0c0: 41902001 la %r9,1(%r2)
    > 00000000001eb0c4: b9040016 lgr %r1,%r6
    > 00000000001eb0c8: b904002b lgr %r2,%r11
    > Call Trace:
    > ( 0xfd797c50)
    > shmem_fill_super+0x13a/0x25c
    > get_sb_single+0xbe/0xdc
    > dev_get_sb+0x2c/0x38
    > devtmpfs_init+0x46/0xc0
    > driver_init+0x22/0x60
    > kernel_init+0x24e/0x3d0
    > kernel_thread_starter+0x6/0xc
    > kernel_thread_starter+0x0/0xc
    >
    > I never tried to boot a kernel with DEVTMPFS enabled on a s390 box.
    > So am wondering if this is supported or not ? If you think this
    > is supported i will send a mail to community on this.

    There is nothing arch specific to devtmpfs. This part crashes because the
    kernel tries to modify the data read-only section which is write protected
    on s390.

    Signed-off-by: Heiko Carstens
    Acked-by: Kay Sievers
    Signed-off-by: Greg Kroah-Hartman

    Heiko Carstens
     

24 Dec, 2009

2 commits

  • 804227380   devtmpfs: unlock mutex in case of string allocation error ... Browse Code »

    Reported-by: Kirill A. Shutemov
    Signed-off-by: Kay Sievers
    Signed-off-by: Greg Kroah-Hartman

    Kay Sievers
     
  • f1f76f865   devtmpfs: Convert dirlock to a mutex ... Browse Code »

    devtmpfs has a rw_lock dirlock which serializes delete_path and
    create_path.

    This code was obviously never tested with the usual set of debugging
    facilities enabled. In the dirlock held sections the code calls:

    - vfs functions which take mutexes
    - kmalloc(, GFP_KERNEL)

    In both code pathes the might sleep warning triggers and spams dmesg.

    Convert the rw_lock to a mutex. There is no reason why this needs to
    be a rwlock.

    Signed-off-by: Thomas Gleixner
    Cc: Kay Sievers
    Cc: stable
    Signed-off-by: Greg Kroah-Hartman

    Thomas Gleixner
     

12 Dec, 2009

5 commits

20 Sep, 2009

1 commit

  • e454cea20   Driver-Core: extend devnode callbacks to provide permissions ... Browse Code »

    This allows subsytems to provide devtmpfs with non-default permissions
    for the device node. Instead of the default mode of 0600, null, zero,
    random, urandom, full, tty, ptmx now have a mode of 0666, which allows
    non-privileged processes to access standard device nodes in case no
    other userspace process applies the expected permissions.

    This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain.

    Signed-off-by: Kay Sievers
    Signed-off-by: Greg Kroah-Hartman

    Kay Sievers
     

16 Sep, 2009

1 commit

  • 2b2af54a5   Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev ... Browse Code »

    Devtmpfs lets the kernel create a tmpfs instance called devtmpfs
    very early at kernel initialization, before any driver-core device
    is registered. Every device with a major/minor will provide a
    device node in devtmpfs.

    Devtmpfs can be changed and altered by userspace at any time,
    and in any way needed - just like today's udev-mounted tmpfs.
    Unmodified udev versions will run just fine on top of it, and will
    recognize an already existing kernel-created device node and use it.
    The default node permissions are root:root 0600. Proper permissions
    and user/group ownership, meaningful symlinks, all other policy still
    needs to be applied by userspace.

    If a node is created by devtmps, devtmpfs will remove the device node
    when the device goes away. If the device node was created by
    userspace, or the devtmpfs created node was replaced by userspace, it
    will no longer be removed by devtmpfs.

    If it is requested to auto-mount it, it makes init=/bin/sh work
    without any further userspace support. /dev will be fully populated
    and dynamic, and always reflect the current device state of the kernel.
    With the commonly used dynamic device numbers, it solves the problem
    where static devices nodes may point to the wrong devices.

    It is intended to make the initial bootup logic simpler and more robust,
    by de-coupling the creation of the inital environment, to reliably run
    userspace processes, from a complex userspace bootstrap logic to provide
    a working /dev.

    Signed-off-by: Kay Sievers
    Signed-off-by: Jan Blunck
    Tested-By: Harald Hoyer
    Tested-By: Scott James Remnant
    Signed-off-by: Greg Kroah-Hartman

    Kay Sievers