Eric Lee / smarc-fsl-linux-kernel

13 Feb, 2015

1 commit

26 Apr, 2014

1 commit

04 Apr, 2014

1 commit

  • bcccff93a   kobject: don't block for each kobject_uevent ... Browse Code »

    Currently kobject_uevent has somewhat unpredictable semantics. The
    point is, since it may call a usermode helper and wait for it to execute
    (UMH_WAIT_EXEC), it is impossible to say for sure what lock dependencies
    it will introduce for the caller - strictly speaking it depends on what
    fs the binary is located on and the set of locks fork may take. There
    are quite a few kobject_uevent's users that do not take this into
    account and call it with various mutexes taken, e.g. rtnl_mutex,
    net_mutex, which might potentially lead to a deadlock.

    Since there is actually no reason to wait for the usermode helper to
    execute there, let's make kobject_uevent start the helper asynchronously
    with the aid of the UMH_NO_WAIT flag.

    Personally, I'm interested in this, because I really want kobject_uevent
    to be called under the slab_mutex in the slub implementation as it used
    to be some time ago, because it greatly simplifies synchronization and
    automatically fixes a kmemcg-related race. However, there was a
    deadlock detected on an attempt to call kobject_uevent under the
    slab_mutex (see https://lkml.org/lkml/2012/1/14/45), which was reported
    to be fixed by releasing the slab_mutex for kobject_uevent.

    Unfortunately, there was no information about who exactly blocked on the
    slab_mutex causing the usermode helper to stall, neither have I managed
    to find this out or reproduce the issue.

    BTW, this is not the first attempt to make kobject_uevent use
    UMH_NO_WAIT. Previous one was made by commit f520360d93cd ("kobject:
    don't block for each kobject_uevent"), but it was wrong (it passed
    arguments allocated on stack to async thread) so it was reverted in
    05f54c13cd0c ("Revert "kobject: don't block for each kobject_uevent".").
    It targeted on speeding up the boot process though.

    Signed-off-by: Vladimir Davydov
    Cc: Greg KH
    Cc: Christoph Lameter
    Cc: Pekka Enberg
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Vladimir Davydov
     

20 Jan, 2014

1 commit

  • 82ef3d5d5   net: fix "queues" uevent between network namespaces ... Browse Code »

    When I create a new namespace with 'ip netns add net0', or add/remove
    new links in a namespace with 'ip link add/delete type veth', rx/tx
    queues events can be got in all namespaces. That is because rx/tx queue
    ktypes do not have namespace support, and their kobj parents are setted to
    NULL. This patch is to fix it.

    Reported-by: Libo Chen
    Signed-off-by: Libo Chen
    Signed-off-by: Weilong Chen
    Acked-by: Greg Kroah-Hartman
    Signed-off-by: David S. Miller

    Weilong Chen
     

09 Sep, 2012

2 commits

  • 9f00d9776   netlink: hide struct module parameter in netlink_kernel_create ... Browse Code »

    This patch defines netlink_kernel_create as a wrapper function of
    __netlink_kernel_create to hide the struct module *me parameter
    (which seems to be THIS_MODULE in all existing netlink subsystems).

    Suggested by David S. Miller.

    Signed-off-by: Pablo Neira Ayuso
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     
  • 9785e10ae   netlink: kill netlink_set_nonroot ... Browse Code »

    Replace netlink_set_nonroot by one new field `flags' in
    struct netlink_kernel_cfg that is passed to netlink_kernel_create.

    This patch also renames NL_NONROOT_* to NL_CFG_F_NONROOT_* since
    now the flags field in nl_table is generic (so we can add more
    flags if needed in the future).

    Also adjust all callers in the net-next tree to use these flags
    instead of netlink_set_nonroot.

    Signed-off-by: Pablo Neira Ayuso
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     

30 Jun, 2012

1 commit

  • a31f2d17b   netlink: add netlink_kernel_cfg parameter to netlink_kernel_create ... Browse Code »

    This patch adds the following structure:

    struct netlink_kernel_cfg {
    unsigned int groups;
    void (*input)(struct sk_buff *skb);
    struct mutex *cb_mutex;
    };

    That can be passed to netlink_kernel_create to set optional configurations
    for netlink kernel sockets.

    I've populated this structure by looking for NULL and zero parameters at the
    existing code. The remaining parameters that always need to be set are still
    left in the original interface.

    That includes optional parameters for the netlink socket creation. This allows
    easy extensibility of this interface in the future.

    This patch also adapts all callers to use this new interface.

    Signed-off-by: Pablo Neira Ayuso
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     

25 Mar, 2012

1 commit

  • 11bcb3284   Merge tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux ... Browse Code »

    Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker:
    "Fix up files in fs/ and lib/ dirs to only use module.h if they really
    need it.

    These are trivial in scope vs the work done previously. We now have
    things where any few remaining cleanups can be farmed out to arch or
    subsystem maintainers, and I have done so when possible. What is
    remaining here represents the bits that don't clearly lie within a
    single arch/subsystem boundary, like the fs dir and the lib dir.

    Some duplicate includes arising from overlapping fixes from
    independent subsystem maintainer submissions are also quashed."

    Fix up trivial conflicts due to clashes with other include file cleanups
    (including some due to the previous bug.h cleanup pull).

    * tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
    lib: reduce the use of module.h wherever possible
    fs: reduce the use of module.h wherever possible
    includecheck: delete any duplicate instances of module.h

    Linus Torvalds
     

09 Mar, 2012

1 commit

  • 7b60a18da   uevent: send events in correct order according to seqnum (v3) ... Browse Code »
    1

    The queue handling in the udev daemon assumes that the events are
    ordered.

    Before this patch uevent_seqnum is incremented under sequence_lock,
    than an event is send uner uevent_sock_mutex. I want to say that code
    contained a window between incrementing seqnum and sending an event.

    This patch locks uevent_sock_mutex before incrementing uevent_seqnum.

    v2: delete sequence_lock, uevent_seqnum is protected by uevent_sock_mutex
    v3: unlock the mutex before the goto exit

    Thanks for Kay for the comments.

    Signed-off-by: Andrew Vagin
    Tested-By: Kay Sievers
    Cc: stable
    Signed-off-by: Greg Kroah-Hartman

    Andrew Vagin
     

08 Mar, 2012

1 commit

10 Dec, 2011

1 commit

23 Aug, 2011

1 commit

  • ebf4127cd   kobj_uevent: Ignore if some listeners cannot handle message ... Browse Code »
    1

    kobject_uevent() uses a multicast socket and should ignore
    if one of listeners cannot handle messages or nobody is
    listening at all.

    Easily reproducible when a process in system is cloned
    with CLONE_NEWNET flag.

    (See also http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/5256)

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

    Milan Broz
     

24 Aug, 2010

1 commit

05 Jun, 2010

2 commits

22 May, 2010

3 commits

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

  • 9cd43611c   kobject: Constify struct kset_uevent_ops ... Browse Code »

    Constify struct kset_uevent_ops.

    This is part of the ops structure constification
    effort started by Arjan van de Ven et al.

    Benefits of this constification:

    * prevents modification of data that is shared
    (referenced) by many other structure instances
    at runtime

    * detects/prevents accidental (but not intentional)
    modification attempts on archs that enforce
    read-only kernel data at runtime

    * potentially better optimized code as the compiler
    can assume that the const data cannot be changed

    * the compiler/linker move const data into .rodata
    and therefore exclude them from false sharing

    Signed-off-by: Emese Revfy
    Signed-off-by: Greg Kroah-Hartman

    Emese Revfy
     

17 Apr, 2009

2 commits

  • d094cbe99   driver core: allow non-root users to listen to uevents ... Browse Code »

    Users can read sysfs files, there is no reason they should not be
    allowed to listen to uevents. This lets xorg and other userspace
    programs properly get these messages without having to be root.

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

    Kay Sievers
     
  • 05f54c13c   Revert "kobject: don't block for each kobject_uevent". ... Browse Code »

    This reverts commit f520360d93cdc37de5d972dac4bf3bdef6a7f6a7.

    Tetsuo Handa, running a kernel with CONFIG_DEBUG_PAGEALLOC=y and
    CONFIG_UEVENT_HELPER_PATH=/sbin/hotplug, has been hitting RCU detected
    CPU stalls: it's been spinning in the loop where do_execve() counts up
    the args (but why wasn't fixup_exception working? dunno).

    The recent change, switching kobject_uevent_env() from UMH_WAIT_EXEC
    to UMH_NO_WAIT, is broken: the exec uses args on the local stack here,
    and an env which is kfreed as soon as call_usermodehelper() returns.
    It very much needs to wait for the exec to be done.

    An alternative would be to keep the UMH_NO_WAIT, and complicate the code
    to allocate and free these resources correctly? but no, as GregKH
    pointed out when making the commit, CONFIG_UEVENT_HELPER_PATH="" is a
    much better optimization - though some distros are still saying
    /sbin/hotplug in their .config, yet with no such binary in their initrd
    or their root.

    Reported-by: Tetsuo Handa
    Signed-off-by: Hugh Dickins
    Acked-by: Greg Kroah-Hartman
    Acked-by: Arjan van de Ven
    Acked-by: Will Newton
    Signed-off-by: Linus Torvalds

    Hugh Dickins
     

27 Mar, 2009

1 commit

25 Mar, 2009

2 commits

  • f520360d9   kobject: don't block for each kobject_uevent ... Browse Code »

    Right now, the kobject_uevent code blocks for each uevent that's being
    generated, due to using (for hystoric reasons) UHM_WAIT_EXEC as flag to
    call_usermode_helper(). Specifically, the effect is that each uevent
    that is being sent causes the code to wake up keventd, then block until
    keventd has processed the work. Needless to say, this happens many times
    during the system boot.

    This patches changes that to UHN_NO_WAIT (brilliant name for a constant
    btw) so that we only schedule the work to fire the uevent message, but
    do not wait for keventd to process the work.

    This removes one of the bottlenecks during boot; each one of them is
    only a small effect, but the sum of them does add up.

    [Note, distros that need this are broken, they should be setting
    CONFIG_UEVENT_HELPER_PATH to "", that way this code path will never be
    excuted at all -- gregkh]

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Greg Kroah-Hartman

    Arjan van de Ven
     
  • f67f129e5   Driver core: implement uevent suppress in kobject ... Browse Code »

    This patch implements uevent suppress in kobject and removes it
    from struct device, based on the following ideas:

    1,Uevent sending should be one attribute of kobject, so suppressing it
    in kobject layer is more natural than in device layer. By this way,
    we can do it for other objects embedded with kobject.

    2,It may save several bytes for each instance of struct device.(On my
    omap3(32bit ARM) based box, can save 8bytes per device object)

    This patch also introduces dev_set|get_uevent_suppress() helpers to
    set and query uevent_suppress attribute in case to help kobject
    as private part of struct device in future.

    [This version is against the latest driver-core patch set of Greg,please
    ignore the last version.]

    Signed-off-by: Ming Lei
    Signed-off-by: Greg Kroah-Hartman

    Ming Lei
     

06 Feb, 2009

1 commit

  • ff491a733   netlink: change return-value logic of netlink_broadcast() ... Browse Code »

    Currently, netlink_broadcast() reports errors to the caller if no
    messages at all were delivered:

    1) If, at least, one message has been delivered correctly, returns 0.
    2) Otherwise, if no messages at all were delivered due to skb_clone()
    failure, return -ENOBUFS.
    3) Otherwise, if there are no listeners, return -ESRCH.

    With this patch, the caller knows if the delivery of any of the
    messages to the listeners have failed:

    1) If it fails to deliver any message (for whatever reason), return
    -ENOBUFS.
    2) Otherwise, if all messages were delivered OK, returns 0.
    3) Otherwise, if no listeners, return -ESRCH.

    In the current ctnetlink code and in Netfilter in general, we can add
    reliable logging and connection tracking event delivery by dropping the
    packets whose events were not successfully delivered over Netlink. Of
    course, this option would be settable via /proc as this approach reduces
    performance (in terms of filtered connections per seconds by a stateful
    firewall) but providing reliable logging and event delivery (for
    conntrackd) in return.

    This patch also changes some clients of netlink_broadcast() that
    may report ENOBUFS errors via printk. This error handling is not
    of any help. Instead, the userspace daemons that are listening to
    those netlink messages should resync themselves with the kernel-side
    if they hit ENOBUFS.

    BTW, netlink_broadcast() clients include those that call
    cn_netlink_send(), nlmsg_multicast() and genlmsg_multicast() since they
    internally call netlink_broadcast() and return its error value.

    Signed-off-by: Pablo Neira Ayuso
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     

07 Jan, 2009

2 commits

27 Jul, 2008

1 commit

  • 5cd2b459d   Use WARN() in lib/ ... Browse Code »

    Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes
    part of the warning section for better reporting/collection. In addition, one
    of the if() clauses collapes into the WARN() entirely now.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

22 Jul, 2008

1 commit

  • 0ad1d6f37   kobject: Transmit return value of call_usermodehelper() to caller ... Browse Code »

    kobject_uevent_env() drops the return value of call_usermodehelper().
    It will make upper caller, such as dm_send_uevents(), to lose error
    information.

    BTW, Previously kobject_uevent_env() transmitted return of
    call_usermodehelper() to callers, but
    commit 5f123fbd80f4f788554636f02bf73e40f914e0d6
    "[PATCH] merge kobject_uevent and kobject_hotplug" removed it.

    Signed-off-by: Wang Chen
    Cc: Kay Sievers
    Signed-off-by: Greg Kroah-Hartman

    Wang Chen
     

30 Apr, 2008

1 commit

04 Apr, 2008

2 commits

31 Mar, 2008

1 commit

  • a9edadbf7   fix uevent action-string regression ... Browse Code »

    Mark Lord wrote:
    >
    > On boot, syslog is flooded with "uevent: unsupported action-string;" messages.
    ..
    > Mar 28 14:43:29 shrimp kernel: tty ptyqd: uevent: unsupported
    > action-string; this will be ignored in a future kernel version
    > Mar 28 14:43:29 shrimp kernel: tty ptyqe: uevent: unsupported
    > action-string; this will be ignored in a future kernel version
    > Mar 28 14:43:29 shrimp kernel: tty ptyqf: uevent: unsupported
    > action-string; this will be ignored in a future kernel version
    > Mar 28 14:43:29 shrimp kernel: tty ptyr0: uevent: unsupported
    > action-string; this will be ignored in a future kernel version
    ..

    These messages are a regression compared with 2.6.24, which did not
    flood the syslog with them.

    The actual underlying problem was introduced in 2.6.23, when somebody
    made the string parsing no longer accept nul-terminated strings as a
    valid input to store_uevent().

    Eg. "add\0" was valid prior to 2.6.23, where the code regressed to
    require "add" without the '\0'.

    This patch fixes the 2.6.23 / 2.6.24 regressions, by having the code
    once again tolerate the trailing '\0', if present.

    According to GregKH, this mainly affects older Ubuntu systems, such as
    the one I have here that requires this fix.

    Signed-off-by: Mark Lord
    Signed-off-by: Linus Torvalds

    Mark Lord
     

28 Mar, 2008

1 commit

25 Jan, 2008

3 commits

  • e374a2bfe   Kobject: fix coding style issues in kobject c files ... Browse Code »

    Clean up the kobject.c and kobject_uevent.c files to follow the
    proper coding style rules.

    Signed-off-by: Greg Kroah-Hartman

    Greg Kroah-Hartman
     
  • 0f4dafc05   Kobject: auto-cleanup on final unref ... Browse Code »

    We save the current state in the object itself, so we can do proper
    cleanup when the last reference is dropped.

    If the initial reference is dropped, the object will be removed from
    sysfs if needed, if an "add" event was sent, "remove" will be send, and
    the allocated resources are released.

    This allows us to clean up some driver core usage as well as allowing us
    to do other such changes to the rest of the kernel.

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

    Kay Sievers
     
  • 9f66fa2a4   kobject: clean up debugging messages ... Browse Code »

    The kobject debugging messages are a mess. This provides a unified
    message that makes them actually useful.

    The format for new kobject debug messages should be:
    kobject: 'KOBJECT_NAME' (ADDRESS): FUNCTION_NAME: message.\n

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

    Greg Kroah-Hartman
     

20 Oct, 2007

1 commit

13 Oct, 2007

1 commit