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2017-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Just simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19kobject: factorize skb setup in kobject_uevent_net_broadcast()Eric Dumazet
We can build one skb and let it be cloned in netlink. This is much faster, and use less memory (all clones will share the same skb->head) Tested: time perf record (for f in `seq 1 3000` ; do ip netns add tast$f; done) [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 4.110 MB perf.data (~179584 samples) ] real 0m24.227s # instead of 0m52.554s user 0m0.329s sys 0m23.753s # instead of 0m51.375s 14.77% ip [kernel.kallsyms] [k] __ip6addrlbl_add 14.56% ip [kernel.kallsyms] [k] netlink_broadcast_filtered 11.65% ip [kernel.kallsyms] [k] netlink_has_listeners 6.19% ip [kernel.kallsyms] [k] _raw_spin_lock_irqsave 5.66% ip [kernel.kallsyms] [k] kobject_uevent_env 4.97% ip [kernel.kallsyms] [k] memset_erms 4.67% ip [kernel.kallsyms] [k] refcount_sub_and_test 4.41% ip [kernel.kallsyms] [k] _raw_read_lock 3.59% ip [kernel.kallsyms] [k] refcount_inc_not_zero 3.13% ip [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore 1.55% ip [kernel.kallsyms] [k] __wake_up 1.20% ip [kernel.kallsyms] [k] strlen 1.03% ip [kernel.kallsyms] [k] __wake_up_common 0.93% ip [kernel.kallsyms] [k] consume_skb 0.92% ip [kernel.kallsyms] [k] netlink_trim 0.87% ip [kernel.kallsyms] [k] insert_header 0.63% ip [kernel.kallsyms] [k] unmap_page_range Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19kobject: copy env blob in one goEric Dumazet
No need to iterate over strings, just copy in one efficient memcpy() call. Tested: time perf record "(for f in `seq 1 3000` ; do ip netns add tast$f; done)" [ perf record: Woken up 10 times to write data ] [ perf record: Captured and wrote 8.224 MB perf.data (~359301 samples) ] real 0m52.554s # instead of 1m7.492s user 0m0.309s sys 0m51.375s # instead of 1m6.875s 9.88% ip [kernel.kallsyms] [k] netlink_broadcast_filtered 8.86% ip [kernel.kallsyms] [k] string 7.37% ip [kernel.kallsyms] [k] __ip6addrlbl_add 5.68% ip [kernel.kallsyms] [k] netlink_has_listeners 5.52% ip [kernel.kallsyms] [k] memcpy_erms 4.76% ip [kernel.kallsyms] [k] __alloc_skb 4.54% ip [kernel.kallsyms] [k] vsnprintf 3.94% ip [kernel.kallsyms] [k] format_decode 3.80% ip [kernel.kallsyms] [k] kmem_cache_alloc_node_trace 3.71% ip [kernel.kallsyms] [k] kmem_cache_alloc_node 3.66% ip [kernel.kallsyms] [k] kobject_uevent_env 3.38% ip [kernel.kallsyms] [k] strlen 2.65% ip [kernel.kallsyms] [k] _raw_spin_lock_irqsave 2.20% ip [kernel.kallsyms] [k] kfree 2.09% ip [kernel.kallsyms] [k] memset_erms 2.07% ip [kernel.kallsyms] [k] ___cache_free 1.95% ip [kernel.kallsyms] [k] kmem_cache_free 1.91% ip [kernel.kallsyms] [k] _raw_read_lock 1.45% ip [kernel.kallsyms] [k] ksize 1.25% ip [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore 1.00% ip [kernel.kallsyms] [k] widen_string Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19kobject: add kobject_uevent_net_broadcast()Eric Dumazet
This removes some #ifdef pollution and will ease follow up patches. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18driver core: suppress sending MODALIAS in UNBIND ueventsDmitry Torokhov
The current udev rules cause modules to be loaded on all device events save for "remove". With the introduction of KOBJ_BIND/KOBJ_UNBIND this causes issues, as driver modules that have devices bound to their drivers get immediately reloaded, and it appears to the user that module unloading doe snot work. The standard udev matching rule is foillowing: ENV{MODALIAS}=="?*", RUN{builtin}+="kmod load $env{MODALIAS}" Given that MODALIAS data is not terribly useful for UNBIND event, let's zap it from the generated uevent environment until we get userspace updated with the correct udev rule that only loads modules on "add" event. Reported-by: Jakub Kicinski <kubakici@wp.pl> Tested-by: Jakub Kicinski <kubakici@wp.pl> Fixes: 1455cf8dbfd0 ("driver core: emit uevents when device is bound ...") Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-22Merge branch 'bind_unbind' into driver-core-nextGreg Kroah-Hartman
This merges the bind_unbind driver core feature into the driver-core-next branch. bind_unbind is a branch so that others can pull and work off of it safely. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-22driver core: emit uevents when device is bound to a driverDmitry Torokhov
There are certain touch controllers that may come up in either normal (application) or boot mode, depending on whether firmware/configuration is corrupted when they are powered on. In boot mode the kernel does not create input device instance (because it does not necessarily know the characteristics of the input device in question). Another number of controllers does not store firmware in a non-volatile memory, and they similarly need to have firmware loaded before input device instance is created. There are also other types of devices with similar behavior. There is a desire to be able to trigger firmware loading via udev, but it has to happen only when driver is bound to a physical device (i2c or spi). These udev actions can not use ADD events, as those happen too early, so we are introducing BIND and UNBIND events that are emitted at the right moment. Also, many drivers create additional driver-specific device attributes when binding to the device, to provide userspace with additional controls. The new events allow userspace to adjust these driver-specific attributes without worrying that they are not there yet. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25kobject: support passing in variables for synthetic ueventsPeter Rajnoha
This patch makes it possible to pass additional arguments in addition to uevent action name when writing /sys/.../uevent attribute. These additional arguments are then inserted into generated synthetic uevent as additional environment variables. Before, we were not able to pass any additional uevent environment variables for synthetic uevents. This made it hard to identify such uevents properly in userspace to make proper distinction between genuine uevents originating from kernel and synthetic uevents triggered from userspace. Also, it was not possible to pass any additional information which would make it possible to optimize and change the way the synthetic uevents are processed back in userspace based on the originating environment of the triggering action in userspace. With the extra additional variables, we are able to pass through this extra information needed and also it makes it possible to synchronize with such synthetic uevents as they can be clearly identified back in userspace. The format for writing the uevent attribute is following: ACTION [UUID [KEY=VALUE ...] There's no change in how "ACTION" is recognized - it stays the same ("add", "change", "remove"). The "ACTION" is the only argument required to generate synthetic uevent, the rest of arguments, that this patch adds support for, are optional. The "UUID" is considered as transaction identifier so it's possible to use the same UUID value for one or more synthetic uevents in which case we logically group these uevents together for any userspace listeners. The "UUID" is expected to be in "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" format where "x" is a hex digit. The value appears in uevent as "SYNTH_UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" environment variable. The "KEY=VALUE" pairs can contain alphanumeric characters only. It's possible to define zero or more more pairs - each pair is then delimited by a space character " ". Each pair appears in synthetic uevents as "SYNTH_ARG_KEY=VALUE" environment variable. That means the KEY name gains "SYNTH_ARG_" prefix to avoid possible collisions with existing variables. To pass the "KEY=VALUE" pairs, it's also required to pass in the "UUID" part for the synthetic uevent first. If "UUID" is not passed in, the generated synthetic uevent gains "SYNTH_UUID=0" environment variable automatically so it's possible to identify this situation in userspace when reading generated uevent and so we can still make a difference between genuine and synthetic uevents. Signed-off-by: Peter Rajnoha <prajnoha@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28kobject: improve function-level documentationJulia Lawall
In the first case, rename the second variable to correspond to the name found in the function parameter list. In the remaining cases, reorder the variables to correspond to their order in the parameter list. Issue detected using Coccinelle (http://coccinelle.lip6.fr/) Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-12lib/kobject_uevent.c: remove redundant includeRasmus Villemoes
The file doesn't seem to use anything from linux/user_namespace.h, and removing it yields byte-identical object code and strictly fewer dependencies in the .cmd file. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-25kobject: Make support for uevent_helper optional.Michael Marineau
Support for uevent_helper, aka hotplug, is not required on many systems these days but it can still be enabled via sysfs or sysctl. Reported-by: Darren Shepherd <darren.s.shepherd@gmail.com> Signed-off-by: Michael Marineau <mike@marineau.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-03kobject: don't block for each kobject_ueventVladimir Davydov
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 <vdavydov@parallels.com> Cc: Greg KH <greg@kroah.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-19net: fix "queues" uevent between network namespacesWeilong Chen
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 <chenlibo@huawei.com> Signed-off-by: Libo Chen <chenlibo@huawei.com> Signed-off-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-08netlink: hide struct module parameter in netlink_kernel_createPablo Neira Ayuso
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 <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-08netlink: kill netlink_set_nonrootPablo Neira Ayuso
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 <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-29netlink: add netlink_kernel_cfg parameter to netlink_kernel_createPablo Neira Ayuso
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 <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-24Merge tag 'module-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 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
2012-03-08uevent: send events in correct order according to seqnum (v3)Andrew Vagin
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 <avagin@openvz.org> Tested-By: Kay Sievers <kay.sievers@vrfy.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-07lib: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-09driver-core: skip uevent generation when nobody is listeningKay Sievers
Most network namespaces unlikely have listeners to uevents, and should benefit from skipping all the string copies. Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22kobj_uevent: Ignore if some listeners cannot handle messageMilan Broz
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 <mbroz@redhat.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-23kobject_uevent: fix typo in commentsXiaotian Feng
s/ending/sending, s/kobject_uevent()/kobject_uevent_env() in the comments. Signed-off-by: Xiaotian Feng <xtfeng@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-04kobject: free memory if netlink_kernel_create() failsDan Carpenter
There is a kfree(ue_sk) missing on the error path if netlink_kernel_create() fails. Signed-off-by: Dan Carpenter <error27@gmail.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-04lib/kobject_uevent.c: fix CONIG_NET=n warningAndrew Morton
lib/kobject_uevent.c:87: warning: 'kobj_bcast_filter' defined but not used Repairs "hotplug: netns aware uevent_helper" Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21hotplug: netns aware uevent_helperEric W. Biederman
It only makes sense for uevent_helper to get events in the intial namespaces. It's invocation is not per namespace and it is not clear how we could make it's invocation namespace aware. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21kobj: Send hotplug events in the proper namespace.Eric W. Biederman
Utilize netlink_broacast_filtered to allow sending hotplug events in the proper namespace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21kobject: Send hotplug events in all network namespacesEric W. Biederman
Open a copy of the uevent kernel socket in each network namespace so we can send uevents in all network namespaces. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit 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>
2010-03-07kobject: Constify struct kset_uevent_opsEmese Revfy
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 <re.emese@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16driver core: allow non-root users to listen to ueventsKay Sievers
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 <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16Revert "kobject: don't block for each kobject_uevent".Hugh Dickins
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 <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Hugh Dickins <hugh@veritas.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Will Newton <will.newton@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-26Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller
Conflicts: drivers/net/wimax/i2400m/usb-notif.c
2009-03-24kobject: don't block for each kobject_ueventArjan van de Ven
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 <arjan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24Driver core: implement uevent suppress in kobjectMing Lei
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 <tom.leiming@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-02-05netlink: change return-value logic of netlink_broadcast()Pablo Neira Ayuso
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 <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-06kobject: return the result of uevent sending by netlinkMing Lei
We need to return the result of uevent sending by netlink to caller, when uevent_helper is disabled and CONFIG_NET is defined. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06uevent: don't pass envp_ext[] as format string in kobject_uevent_env()Tejun Heo
kobject_uevent_env() uses envp_ext[] as verbatim format string which can cause problems ranging from unexpectedly mangled string to oops if a string in envp_ext[] contains substring which can be interpreted as format. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-26Use WARN() in lib/Arjan van de Ven
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 <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-21kobject: Transmit return value of call_usermodehelper() to callerWang Chen
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 <wangchen@cn.fujitsu.com> Cc: Kay Sievers <kay.sievers@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-30lib: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-03Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
2008-04-03[NETNS]: Declare init_net even without CONFIG_NET defined.Denis V. Lunev
This does not look good, but there is no other choice. The compilation without CONFIG_NET is broken and can not be fixed with ease. After that there is no need for the following commits: 1567ca7eec7664b8be3b07755ac59dc1b1ec76cb 3edf8fa5ccf10688a9280b5cbca8ed3947c42866 2d38f9a4f8d2ebdc799f03eecf82345825495711 Revert them. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-30fix uevent action-string regressionMark Lord
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 <mlord@pobox.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-27[NETNS]: Do no include NET related headers if CONFIG_NET is not set.Denis V. Lunev
This fix broken compilation for 'allnoconfig'. This was introduced by Introduced by commit 1218854afa6f659be90b748cf1bc7badee954a35 ("[NET] NETNS: Omit seq_net_private->net without CONFIG_NET_NS.") Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-24Kobject: fix coding style issues in kobject c filesGreg Kroah-Hartman
Clean up the kobject.c and kobject_uevent.c files to follow the proper coding style rules. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Kobject: auto-cleanup on final unrefKay Sievers
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 <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24kobject: clean up debugging messagesGreg Kroah-Hartman
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 <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-19Fix misspellings of "system", "controller", "interrupt" and "necessary".Robert P. J. Day
Fix the various misspellings of "system", controller", "interrupt" and "[un]necessary". Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-12Driver core: kerneldoc - kobject_uevent_env is not "usually KOBJ_MOVE"Kay Sievers
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12Driver core: exclude kobject_uevent.c for !CONFIG_HOTPLUGKay Sievers
Move uevent specific logic from the core into kobject_uevent.c, which does no longer require to link the unused string array if hotplug is not compiled in. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>