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* cgroup: replace cftype->write_string() with cftype->write()Tejun Heo2014-05-133-37/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert all cftype->write_string() users to the new cftype->write() which maps directly to kernfs write operation and has full access to kernfs and cgroup contexts. The conversions are mostly mechanical. * @css and @cft are accessed using of_css() and of_cft() accessors respectively instead of being specified as arguments. * Should return @nbytes on success instead of 0. * @buf is not trimmed automatically. Trim if necessary. Note that blkcg and netprio don't need this as the parsers already handle whitespaces. cftype->write_string() has no user left after the conversions and removed. While at it, remove unnecessary local variable @p in cgroup_subtree_control_write() and stale comment about CGROUP_LOCAL_BUFFER_SIZE in cgroup_freezer.c. This patch doesn't introduce any visible behavior changes. v2: netprio was missing from conversion. Converted. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Aristeu Rozanski <arozansk@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: "David S. Miller" <davem@davemloft.net>
* cgroup: implement cftype->write()Tejun Heo2014-05-131-6/+8
| | | | | | | | | | | | | | | | | | | | | | | During the recent conversion to kernfs, cftype's seq_file operations are updated so that they are directly mapped to kernfs operations and thus can fully access the associated kernfs and cgroup contexts; however, write path hasn't seen similar updates and none of the existing write operations has access to, for example, the associated kernfs_open_file. Let's introduce a new operation cftype->write() which maps directly to the kernfs write operation and has access to all the arguments and contexts. This will replace ->write_string() and ->trigger() and ease manipulation of kernfs active protection from cgroup file operations. Two accessors - of_cft() and of_css() - are introduced to enable accessing the associated cgroup context from cftype->write() which only takes kernfs_open_file for the context information. The accessors for seq_file operations - seq_cft() and seq_css() - are rewritten to wrap the of_ accessors. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: rename css_tryget*() to css_tryget_online*()Tejun Heo2014-05-134-26/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike the more usual refcnting, what css_tryget() provides is the distinction between online and offline csses instead of protection against upping a refcnt which already reached zero. cgroup is planning to provide actual tryget which fails if the refcnt already reached zero. Let's rename the existing trygets so that they clearly indicate that they're onliness. I thought about keeping the existing names as-are and introducing new names for the planned actual tryget; however, given that each controller participates in the synchronization of the online state, it seems worthwhile to make it explicit that these functions are about on/offline state. Rename css_tryget() to css_tryget_online() and css_tryget_from_dir() to css_tryget_online_from_dir(). This is pure rename. v2: cgroup_freezer grew new usages of css_tryget(). Update accordingly. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
* cgroup: use release_agent_path_lock in cgroup_release_agent_show()Tejun Heo2014-05-131-3/+2
| | | | | | | | | | | release_path is now protected by release_agent_path_lock to allow accessing it without grabbing cgroup_mutex; however, cgroup_release_agent_show() was still grabbing cgroup_mutex. Let's convert it to release_agent_path_lock so that we don't have to worry about this one for the planned locking updates. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: use restart_syscall() for retries after offline waits in ↵Tejun Heo2014-05-131-9/+9
| | | | | | | | | | | | | | cgroup_subtree_control_write() After waiting for a child to finish offline, cgroup_subtree_control_write() jumps up to retry from after the input parsing and active protection breaking. This retry makes the scheduled locking update - removal of cgroup_tree_mutex - more difficult. Let's simplify it by returning with restart_syscall() for retries. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: update and fix parsing of "cgroup.subtree_control"Tejun Heo2014-05-131-3/+5
| | | | | | | | | | | | | | | | | | | | | | I was confused that strsep() was equivalent to strtok_r() in skipping over consecutive delimiters. strsep() just splits at the first occurrence of one of the delimiters which makes the parsing very inflexible, which makes allowing multiple whitespace chars as delimters kinda moot. Let's just be consistently strict and require list of tokens separated by spaces. This is what Documentation/cgroups/unified-hierarchy.txt describes too. Also, parsing may access beyond the end of the string if the string ends with spaces or is zero-length. Make sure it skips zero-length tokens. Note that this also ensures that the parser doesn't puke on multiple consecutive spaces. v2: Add zero-length token skipping. v3: Added missing space after "==". Spotted by Li. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: css_release() shouldn't clear cgroup->subsys[]Tejun Heo2014-05-131-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | c1a71504e971 ("cgroup: don't recycle cgroup id until all csses' have been destroyed") made cgroup ID persist until a cgroup is released and add cgroup->subsys[] clearing to css_release() so that css_from_id() doesn't return a css which has already been released which happens before cgroup release; however, the right change here was updating offline_css() to clear cgroup->subsys[] which was done by e32978031016 ("cgroup: cgroup->subsys[] should be cleared after the css is offlined") instead of clearing it from css_release(). We're now clearing cgroup->subsys[] twice. This is okay for traditional hierarchies as a css's lifetime is the same as its cgroup's; however, this confuses unified hierarchy and turning on and off a controller repeatedly using "cgroup.subtree_control" can lead to an oops like the following which happens because cgroup->subsys[] is incorrectly cleared asynchronously by css_release(). BUG: unable to handle kernel NULL pointer dereference at 00000000000000 08 IP: [<ffffffff81130c11>] kill_css+0x21/0x1c0 PGD 1170d067 PUD f0ab067 PMD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 2 PID: 459 Comm: bash Not tainted 3.15.0-rc2-work+ #5 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff880009296710 ti: ffff88000e198000 task.ti: ffff88000e198000 RIP: 0010:[<ffffffff81130c11>] [<ffffffff81130c11>] kill_css+0x21/0x1c0 RSP: 0018:ffff88000e199dc8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8238a968 RDI: ffff880009296f98 RBP: ffff88000e199de0 R08: 0000000000000001 R09: 02b0000000000000 R10: 0000000000000000 R11: ffff880009296fc0 R12: 0000000000000001 R13: ffff88000db6fc58 R14: 0000000000000001 R15: ffff8800139dcc00 FS: 00007ff9160c5740(0000) GS:ffff88001fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 0000000013947000 CR4: 00000000000006e0 Stack: ffff88000e199de0 ffffffff82389160 0000000000000001 ffff88000e199e80 ffffffff8113537f 0000000000000007 ffff88000e74af00 ffff88000e199e48 ffff880009296710 ffff88000db6fc00 ffffffff8239c100 0000000000000002 Call Trace: [<ffffffff8113537f>] cgroup_subtree_control_write+0x85f/0xa00 [<ffffffff8112fd18>] cgroup_file_write+0x38/0x1d0 [<ffffffff8126fc97>] kernfs_fop_write+0xe7/0x170 [<ffffffff811f2ae6>] vfs_write+0xb6/0x1c0 [<ffffffff811f35ad>] SyS_write+0x4d/0xc0 [<ffffffff81d0acd2>] system_call_fastpath+0x16/0x1b Code: 5c 41 5d 41 5e 41 5f 5d c3 90 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb 48 83 ec 08 8b 05 37 ad 29 01 85 c0 0f 85 df 00 00 00 <48> 8b 43 08 48 8b 3b be 01 00 00 00 8b 48 5c d3 e6 e8 49 ff ff RIP [<ffffffff81130c11>] kill_css+0x21/0x1c0 RSP <ffff88000e199dc8> CR2: 0000000000000008 ---[ end trace e7aae1f877c4e1b4 ]--- Remove the unnecessary cgroup->subsys[] clearing from css_release(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: cgroup_idr_lock should be bhTejun Heo2014-05-131-6/+6
| | | | | | | | cgroup_idr_remove() can be invoked from bh leading to lockdep detecting possible AA deadlock (IN_BH/ON_BH). Make the lock bh-safe. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* cgroup: fix offlining child waiting in cgroup_subtree_control_write()Tejun Heo2014-05-131-1/+3
| | | | | | | | | | | | | | | | cgroup_subtree_control_write() waits for offline to complete child-by-child before enabling a controller; however, it has a couple bugs. * It doesn't initialize the wait_queue_t. This can lead to infinite hang on the following schedule() among other things. * It forgets to pin the child before releasing cgroup_tree_mutex and performing schedule(). The child may already be gone by the time it wakes up and invokes finish_wait(). Pin the child being waited on. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* Merge branch 'for-3.15-fixes' of ↵Tejun Heo2014-05-132-68/+50
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup into for-3.16 Pull to receive e37a06f10994 ("cgroup: fix the retry path of cgroup_mount()") to avoid unnecessary conflicts with planned cgroup_tree_mutex removal and also to be able to remove the temp fix added by 36c38fb7144a ("blkcg: use trylock on blkcg_pol_mutex in blkcg_reset_stats()") afterwards. Signed-off-by: Tejun Heo <tj@kernel.org>
| * cgroup: fix rcu_read_lock() leak in update_if_frozen()Tejun Heo2014-05-131-1/+3
| | | | | | | | | | | | | | | | | | | | While updating cgroup_freezer locking, 68fafb77d827 ("cgroup_freezer: replace freezer->lock with freezer_mutex") introduced a bug in update_if_frozen() where it returns with rcu_read_lock() held. Fix it by adding rcu_read_unlock() before returning. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: kbuild test robot <fengguang.wu@intel.com>
| * cgroup_freezer: replace freezer->lock with freezer_mutexTejun Heo2014-05-131-66/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After 96d365e0b86e ("cgroup: make css_set_lock a rwsem and rename it to css_set_rwsem"), css task iterators requires sleepable context as it may block on css_set_rwsem. I missed that cgroup_freezer was iterating tasks under IRQ-safe spinlock freezer->lock. This leads to errors like the following on freezer state reads and transitions. BUG: sleeping function called from invalid context at /work /os/work/kernel/locking/rwsem.c:20 in_atomic(): 0, irqs_disabled(): 0, pid: 462, name: bash 5 locks held by bash/462: #0: (sb_writers#7){.+.+.+}, at: [<ffffffff811f0843>] vfs_write+0x1a3/0x1c0 #1: (&of->mutex){+.+.+.}, at: [<ffffffff8126d78b>] kernfs_fop_write+0xbb/0x170 #2: (s_active#70){.+.+.+}, at: [<ffffffff8126d793>] kernfs_fop_write+0xc3/0x170 #3: (freezer_mutex){+.+...}, at: [<ffffffff81135981>] freezer_write+0x61/0x1e0 #4: (rcu_read_lock){......}, at: [<ffffffff81135973>] freezer_write+0x53/0x1e0 Preemption disabled at:[<ffffffff81104404>] console_unlock+0x1e4/0x460 CPU: 3 PID: 462 Comm: bash Not tainted 3.15.0-rc1-work+ #10 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 ffff88000916a6d0 ffff88000e0a3da0 ffffffff81cf8c96 0000000000000000 ffff88000e0a3dc8 ffffffff810cf4f2 ffffffff82388040 ffff880013aaf740 0000000000000002 ffff88000e0a3de8 ffffffff81d05974 0000000000000246 Call Trace: [<ffffffff81cf8c96>] dump_stack+0x4e/0x7a [<ffffffff810cf4f2>] __might_sleep+0x162/0x260 [<ffffffff81d05974>] down_read+0x24/0x60 [<ffffffff81133e87>] css_task_iter_start+0x27/0x70 [<ffffffff8113584d>] freezer_apply_state+0x5d/0x130 [<ffffffff81135a16>] freezer_write+0xf6/0x1e0 [<ffffffff8112eb88>] cgroup_file_write+0xd8/0x230 [<ffffffff8126d7b7>] kernfs_fop_write+0xe7/0x170 [<ffffffff811f0756>] vfs_write+0xb6/0x1c0 [<ffffffff811f121d>] SyS_write+0x4d/0xc0 [<ffffffff81d08292>] system_call_fastpath+0x16/0x1b freezer->lock used to be used in hot paths but that time is long gone and there's no reason for the lock to be IRQ-safe spinlock or even per-cgroup. In fact, given the fact that a cgroup may contain large number of tasks, it's not a good idea to iterate over them while holding IRQ-safe spinlock. Let's simplify locking by replacing per-cgroup freezer->lock with global freezer_mutex. This also makes the comments explaining the intricacies of policy inheritance and the locking around it as the states are protected by a common mutex. The conversion is mostly straight-forward. The followings are worth mentioning. * freezer_css_online() no longer needs double locking. * freezer_attach() now performs propagation simply while holding freezer_mutex. update_if_frozen() race no longer exists and the comment is removed. * freezer_fork() now tests whether the task is in root cgroup using the new task_css_is_root() without doing rcu_read_lock/unlock(). If not, it grabs freezer_mutex and performs the operation. * freezer_read() and freezer_change_state() grab freezer_mutex across the whole operation and pin the css while iterating so that each descendant processing happens in sleepable context. Fixes: 96d365e0b86e ("cgroup: make css_set_lock a rwsem and rename it to css_set_rwsem") Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
| * cgroup: introduce task_css_is_root()Tejun Heo2014-05-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Determining the css of a task usually requires RCU read lock as that's the only thing which keeps the returned css accessible till its reference is acquired; however, testing whether a task belongs to the root can be performed without dereferencing the returned css by comparing the returned pointer against the root one in init_css_set[] which never changes. Implement task_css_is_root() which can be invoked in any context. This will be used by the scheduled cgroup_freezer change. v2: cgroup no longer supports modular controllers. No need to export init_css_set. Pointed out by Li. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | kernel/cpuset.c: convert printk to pr_foo()Fabian Frederick2014-05-061-7/+4
| | | | | | | | | | | | | | Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | kernel/cpuset.c: kernel-doc fixesFabian Frederick2014-05-061-5/+6
| | | | | | | | | | | | | | | | | | This patch also converts seq_printf to seq_puts Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | kernel/cgroup.c: fix 2 kernel-doc warningsFabian Frederick2014-05-051-2/+2
| | | | | | | | | | | | | | | | | | | | Fix typo and variable name. tj: Updated @cgrp argument description in cgroup_destroy_css_killed() Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Tejun Heo <tj@kernel.org>
* | cgroup, memcg: implement css->id and convert css_from_id() to use itTejun Heo2014-05-041-21/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now, cgroup->id has been used to identify all the associated csses and css_from_id() takes cgroup ID and returns the matching css by looking up the cgroup and then dereferencing the css associated with it; however, now that the lifetimes of cgroup and css are separate, this is incorrect and breaks on the unified hierarchy when a controller is disabled and enabled back again before the previous instance is released. This patch adds css->id which is a subsystem-unique ID and converts css_from_id() to look up by the new css->id instead. memcg is the only user of css_from_id() and also converted to use css->id instead. For traditional hierarchies, this shouldn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jianyu Zhan <nasa4836@gmail.com> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup: update init_css() into init_and_link_css()Tejun Heo2014-05-041-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | init_css() takes the cgroup the new css belongs to as an argument and initializes the new css's ->cgroup and ->parent pointers but doesn't acquire the matching reference counts. After the previous patch, create_css() puts init_css() and reference acquisition right next to each other. Let's move reference acquistion into init_css() and rename the function to init_and_link_css(). This makes sense and is easier to follow. This makes the root csses to hold a reference on cgrp_dfl_root.cgrp, which is harmless. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup: use RCU free in create_css() failure pathTejun Heo2014-05-041-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when create_css() fails in the middle, the half-initialized css is freed by invoking cgroup_subsys->css_free() directly. This patch updates the function so that it invokes RCU free path instead. As the RCU free path puts the parent css and owning cgroup, their references are now acquired right after a new css is successfully allocated. This doesn't make any visible difference now but is to enable implementing css->id and RCU protected lookup by such IDs. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup: protect cgroup_root->cgroup_idr with a spinlockTejun Heo2014-05-041-8/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, cgroup_root->cgroup_idr is protected by cgroup_mutex, which ends up requiring cgroup_put() to be invoked under sleepable context. This is okay for now but is an unusual requirement and we'll soon add css->id which will have the same problem but won't be able to simply grab cgroup_mutex as removal will have to happen from css_release() which can't sleep. Introduce cgroup_idr_lock and idr_alloc/replace/remove() wrappers which protects the idr operations with the lock and use them for cgroup_root->cgroup_idr. cgroup_put() no longer needs to grab cgroup_mutex and css_from_id() is updated to always require RCU read lock instead of either RCU read lock or cgroup_mutex, which doesn't affect the existing users. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup, memcg: allocate cgroup ID from 1Tejun Heo2014-05-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, cgroup->id is allocated from 0, which is always assigned to the root cgroup; unfortunately, memcg wants to use ID 0 to indicate invalid IDs and ends up incrementing all IDs by one. It's reasonable to reserve 0 for special purposes. This patch updates cgroup core so that ID 0 is not used and the root cgroups get ID 1. The ID incrementing is removed form memcg. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup: make flags and subsys_masks unsigned intTejun Heo2014-05-041-19/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to use atomic bitops for cgroup_subsys_state->flags, cgroup_root->flags and various subsys_masks. This patch updates those to use bitwise and/or operations instead and converts them form unsigned long to unsigned int. This makes the fields occupy (marginally) smaller space and makes it clear that they don't require atomicity. This patch doesn't cause any behavior difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | cgroup: Use more current logging styleJoe Perches2014-04-261-13/+15
| | | | | | | | | | | | | | | | | | Use pr_fmt and remove embedded prefixes. Realign modified multi-line statements to open parenthesis. Convert embedded function name to "%s: ", __func__ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | cgroup: replace pr_warning with preferred pr_warnJianyu Zhan2014-04-261-10/+10
| | | | | | | | | | | | | | | | | | | | As suggested by scripts/checkpatch.pl, substitude all pr_warning() with pr_warn(). No functional change. Signed-off-by: Jianyu Zhan <nasa4836@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | cgroup: remove orphaned cgroup_pidlist_seq_operationsJianyu Zhan2014-04-261-11/+0
| | | | | | | | | | | | | | | | | | | | | | 6612f05b88fa309c9 ("cgroup: unify pidlist and other file handling") has removed the only user of cgroup_pidlist_seq_operations : cgroup_pidlist_open(). This patch removes it. Signed-off-by: Jianyu Zhan <nasa4836@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | cgroup: clean up obsolete comment for parse_cgroupfs_options()Jianyu Zhan2014-04-261-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1d5be6b287c8efc87 ("cgroup: move module ref handling into rebind_subsystems()") makes parse_cgroupfs_options() no longer takes refcounts on subsystems. And unified hierachy makes parse_cgroupfs_options not need to call with cgroup_mutex held to protect the cgroup_subsys[]. So this patch removes BUG_ON() and the comment. As the comment doesn't contain useful information afterwards, the whole comment is removed. Signed-off-by: Jianyu Zhan <nasa4836@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | cgroup: implement cgroup.populated for the default hierarchyTejun Heo2014-04-261-4/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cgroup users often need a way to determine when a cgroup's subhierarchy becomes empty so that it can be cleaned up. cgroup currently provides release_agent for it; unfortunately, this mechanism is riddled with issues. * It delivers events by forking and execing a userland binary specified as the release_agent. This is a long deprecated method of notification delivery. It's extremely heavy, slow and cumbersome to integrate with larger infrastructure. * There is single monitoring point at the root. There's no way to delegate management of a subtree. * The event isn't recursive. It triggers when a cgroup doesn't have any tasks or child cgroups. Events for internal nodes trigger only after all children are removed. This again makes it impossible to delegate management of a subtree. * Events are filtered from the kernel side. "notify_on_release" file is used to subscribe to or suppress release event. This is unnecessarily complicated and probably done this way because event delivery itself was expensive. This patch implements interface file "cgroup.populated" which can be used to monitor whether the cgroup's subhierarchy has tasks in it or not. Its value is 0 if there is no task in the cgroup and its descendants; otherwise, 1, and kernfs_notify() notificaiton is triggers when the value changes, which can be monitored through poll and [di]notify. This is a lot ligther and simpler and trivially allows delegating management of subhierarchy - subhierarchy monitoring can block further propgation simply by putting itself or another process in the root of the subhierarchy and monitor events that it's interested in from there without interfering with monitoring higher in the tree. v2: Patch description updated as per Serge. v3: "cgroup.subtree_populated" renamed to "cgroup.populated". The subtree_ prefix was a bit confusing because "cgroup.subtree_control" uses it to denote the tree rooted at the cgroup sans the cgroup itself while the populated state includes the cgroup itself. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Lennart Poettering <lennart@poettering.net>
* | Merge branch 'driver-core-next' of ↵Tejun Heo2014-04-2614-48/+88
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core into for-3.16 Pull in driver-core-next to receive kernfs_notify() updates which will be used by the planned "cgroup.populated" implementation. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | kobject: Make support for uevent_helper optional.Michael Marineau2014-04-252-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2014-04-194-11/+32
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Two fixes: - a SCHED_DEADLINE task selection fix - a sched/numa related lockdep splat fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Check for stop task appearance when balancing happens sched/numa: Fix task_numa_free() lockdep splat
| | * | sched: Check for stop task appearance when balancing happensKirill Tkhai2014-04-173-5/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need to do it like we do for the other higher priority classes.. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> Cc: Michael wang <wangyun@linux.vnet.ibm.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/336561397137116@web27h.yandex.ru Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | sched/numa: Fix task_numa_free() lockdep splatMike Galbraith2014-04-112-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sasha reported that lockdep claims that the following commit: made numa_group.lock interrupt unsafe: 156654f491dd ("sched/numa: Move task_numa_free() to __put_task_struct()") While I don't see how that could be, given the commit in question moved task_numa_free() from one irq enabled region to another, the below does make both gripes and lockups upon gripe with numa=fake=4 go away. Reported-by: Sasha Levin <sasha.levin@oracle.com> Fixes: 156654f491dd ("sched/numa: Move task_numa_free() to __put_task_struct()") Signed-off-by: Mike Galbraith <bitbucket@online.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: torvalds@linux-foundation.org Cc: mgorman@suse.com Cc: akpm@linux-foundation.org Cc: Dave Jones <davej@redhat.com> Link: http://lkml.kernel.org/r/1396860915.5170.5.camel@marge.simpson.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2014-04-191-0/+2
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more networking fixes from David Miller: 1) Fix mlx4_en_netpoll implementation, it needs to schedule a NAPI context, not synchronize it. From Chris Mason. 2) Ipv4 flow input interface should never be zero, it should be LOOPBACK_IFINDEX instead. From Cong Wang and Julian Anastasov. 3) Properly configure MAC to PHY connection in mvneta devices, from Thomas Petazzoni. 4) sys_recv should use SYSCALL_DEFINE. From Jan Glauber. 5) Tunnel driver ioctls do not use the correct namespace, fix from Nicolas Dichtel. 6) Fix memory leak on seccomp filter attach, from Kees Cook. 7) Fix lockdep warning for nested vlans, from Ding Tianhong. 8) Crashes can happen in SCTP due to how the auth_enable value is managed, fix from Vlad Yasevich. 9) Wireless fixes from John W Linville and co. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits) net: sctp: cache auth_enable per endpoint tg3: update rx_jumbo_pending ring param only when jumbo frames are enabled vlan: Fix lockdep warning when vlan dev handle notification seccomp: fix memory leak on filter attach isdn: icn: buffer overflow in icn_command() ip6_tunnel: use the right netns in ioctl handler sit: use the right netns in ioctl handler ip_tunnel: use the right netns in ioctl handler net: use SYSCALL_DEFINEx for sys_recv net: mdio-gpio: Add support for separate MDI and MDO gpio pins net: mdio-gpio: Add support for active low gpio pins net: mdio-gpio: Use devm_ functions where possible ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source() ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif mlx4_en: don't use napi_synchronize inside mlx4_en_netpoll net: mvneta: properly configure the MAC <-> PHY connection in all situations net: phy: add minimal support for QSGMII PHY sfc:On MCDI timeout, issue an FLR (and mark MCDI to fail-fast) mwifiex: fix hung task on command timeout mwifiex: process event before command response ...
| | * | | seccomp: fix memory leak on filter attachKees Cook2014-04-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This sets the correct error code when final filter memory is unavailable, and frees the raw filter no matter what. unreferenced object 0xffff8800d6ea4000 (size 512): comm "sshd", pid 278, jiffies 4294898315 (age 46.653s) hex dump (first 32 bytes): 21 00 00 00 04 00 00 00 15 00 01 00 3e 00 00 c0 !...........>... 06 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!....... backtrace: [<ffffffff8151414e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff811a3a40>] __kmalloc+0x280/0x320 [<ffffffff8110842e>] prctl_set_seccomp+0x11e/0x3b0 [<ffffffff8107bb6b>] SyS_prctl+0x3bb/0x4a0 [<ffffffff8152ef2d>] system_call_fastpath+0x1a/0x1f [<ffffffffffffffff>] 0xffffffffffffffff Reported-by: Masami Ichikawa <masami256@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Masami Ichikawa <masami256@gmail.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | kernel/watchdog.c:touch_softlockup_watchdog(): use raw_cpu_write()Andrew Morton2014-04-191-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix: BUG: using __this_cpu_write() in preemptible [00000000] code: systemd-udevd/497 caller is __this_cpu_preempt_check+0x13/0x20 CPU: 3 PID: 497 Comm: systemd-udevd Tainted: G W 3.15.0-rc1 #9 Hardware name: Hewlett-Packard HP EliteBook 8470p/179B, BIOS 68ICF Ver. F.02 04/27/2012 Call Trace: check_preemption_disabled+0xe1/0xf0 __this_cpu_preempt_check+0x13/0x20 touch_nmi_watchdog+0x28/0x40 Reported-by: Luis Henriques <luis.henriques@canonical.com> Tested-by: Luis Henriques <luis.henriques@canonical.com> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Robert Moore <robert.moore@intel.com> Cc: Lv Zheng <lv.zheng@intel.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | Merge tag 'trace-fixes-v3.15-rc1' of ↵Linus Torvalds2014-04-182-6/+16
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "This contains two fixes. The first is to remove a duplication of creating debugfs files that already exist and causes an error report to be printed due to the failure of the second creation. The second is a memory leak fix that was introduced in 3.14" * tag 'trace-fixes-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/uprobes: Fix uprobe_cpu_buffer memory leak tracing: Do not try to recreated toplevel set_ftrace_* files
| | * | | | tracing/uprobes: Fix uprobe_cpu_buffer memory leakzhangwei(Jovi)2014-04-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Forgot to free uprobe_cpu_buffer percpu page in uprobe_buffer_disable(). Link: http://lkml.kernel.org/p/534F8B3F.1090407@huawei.com Cc: stable@vger.kernel.org # v3.14+ Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | tracing: Do not try to recreated toplevel set_ftrace_* filesSteven Rostedt (Red Hat)2014-04-171-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the restructing of the function tracer working with instances, the "top level" buffer is a bit special, as the function tracing is mapped to the same set of filters. This is done by using a "global_ops" descriptor and having the "set_ftrace_filter" and "set_ftrace_notrace" map to it. When an instance is created, it creates the same files but its for the local instance and not the global_ops. The issues is that the local instance creation shares some code with the global instance one and we end up trying to create th top level "set_ftrace_*" files twice, and on boot up, we get an error like this: Could not create debugfs 'set_ftrace_filter' entry Could not create debugfs 'set_ftrace_notrace' entry The reason they failed to be created was because they were created twice, and the second time gives this error as you can not create the same file twice. Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2014-04-182-2/+5
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Viresh unearthed the following three hickups in the timer/timekeeping code: - Negated check for the result of a clock event selection - A missing early exit in the jiffies update path which causes update_wall_time to be called for nothing causing lock contention and wasted cycles in the timer interrupt - Checking a variable in the NOHZ code enable code for true which can only be set by that very code after the check succeeds. That results in a rock solid runtime disablement of that feature" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz() tick-sched: Don't call update_wall_time() when delta is lesser than tick_period tick-common: Fix wrong check in tick_check_replacement()
| | * | | | | tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz()Viresh Kumar2014-04-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit d689fe222 (NOHZ: Check for nohz active instead of nohz enabled) the tick_nohz_switch_to_nohz() function returns because it checks for the tick_nohz_active flag. This can't be set, because the function itself sets it. Undo the change in tick_nohz_switch_to_nohz(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: linaro-kernel@lists.linaro.org Cc: fweisbec@gmail.com Cc: Arvind.Chauhan@arm.com Cc: linaro-networking@linaro.org Cc: <stable@vger.kernel.org> # 3.13+ Link: http://lkml.kernel.org/r/40939c05f2d65d781b92b20302b02243d0654224.1397537987.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | tick-sched: Don't call update_wall_time() when delta is lesser than tick_periodViresh Kumar2014-04-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In tick_do_update_jiffies64() we are processing ticks only if delta is greater than tick_period. This is what we are supposed to do here and it broke a bit with this patch: commit 47a1b796 (tick/timekeeping: Call update_wall_time outside the jiffies lock) With above patch, we might end up calling update_wall_time() even if delta is found to be smaller that tick_period. Fix this by returning when the delta is less than tick period. [ tglx: Made it a 3 liner and massaged changelog ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: linaro-kernel@lists.linaro.org Cc: fweisbec@gmail.com Cc: Arvind.Chauhan@arm.com Cc: linaro-networking@linaro.org Cc: John Stultz <john.stultz@linaro.org> Cc: <stable@vger.kernel.org> # v3.14+ Link: http://lkml.kernel.org/r/80afb18a494b0bd9710975bcc4de134ae323c74f.1397537987.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | tick-common: Fix wrong check in tick_check_replacement()Viresh Kumar2014-04-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tick_check_replacement() returns if a replacement of clock_event_device is possible or not. It does this as the first check: if (tick_check_percpu(curdev, newdev, smp_processor_id())) return false; Thats wrong. tick_check_percpu() returns true when the device is useable. Check for false instead. [ tglx: Massaged changelog ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: <stable@vger.kernel.org> # v3.11+ Cc: linaro-kernel@lists.linaro.org Cc: fweisbec@gmail.com Cc: Arvind.Chauhan@arm.com Cc: linaro-networking@linaro.org Link: http://lkml.kernel.org/r/486a02efe0246635aaba786e24b42d316438bf3b.1397537987.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2014-04-171-10/+9
| |\ \ \ \ \ \ | | |_|_|/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: "liblockdep fixes and mutex debugging fixes" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/mutex: Fix debug_mutexes tools/liblockdep: Add proper versioning to the shared obj tools/liblockdep: Ignore asmlinkage and visible
| | * | | | | locking/mutex: Fix debug_mutexesPeter Zijlstra2014-04-111-10/+9
| | | |_|/ / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | debug_mutex_unlock() would bail when !debug_locks and forgets to actually unlock. Reported-by: "Michael L. Semon" <mlsemon35@gmail.com> Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name> Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Fixes: 6f008e72cd11 ("locking/mutex: Fix debug checks") Tested-by: Dave Jones <davej@redhat.com> Cc: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140410141559.GE13658@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2014-04-161-9/+8
| |\ \ \ \ \ | | |_|/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) Fix BPF filter validation of netlink attribute accesses, from Mathias Kruase. 2) Netfilter conntrack generation seqcount not initialized properly, from Andrey Vagin. 3) Fix comparison mask computation on big-endian in nft_cmp_fast(), from Patrick McHardy. 4) Properly limit MTU over ipv6, from Eric Dumazet. 5) Fix seccomp system call argument population on 32-bit, from Daniel Borkmann. 6) skb_network_protocol() should not use hard-coded ETH_HLEN, instead skb->mac_len needs to be used. From Vlad Yasevich. 7) We have several cases of using socket based communications to implement a tunnel. For example, some tunnels are encapsulations over UDP so we use an internal kernel UDP socket to do the transmits. These tunnels should behave just like other software devices and pass the packets on down to the next layer. Most importantly we want the top-level socket (eg TCP) that created the traffic to be charged for the SKB memory. However, once you get into the IP output path, we have code that assumed that whatever was attached to skb->sk is an IP socket. To keep the top-level socket being charged for the SKB memory, whilst satisfying the needs of the IP output path, we now pass in an explicit 'sk' argument. From Eric Dumazet. 8) ping_init_sock() leaks group info, from Xiaoming Wang. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits) cxgb4: use the correct max size for firmware flash qlcnic: Fix MSI-X initialization code ip6_gre: don't allow to remove the fb_tunnel_dev ipv4: add a sock pointer to dst->output() path. ipv4: add a sock pointer to ip_queue_xmit() driver/net: cosa driver uses udelay incorrectly at86rf230: fix __at86rf230_read_subreg function at86rf230: remove check if AVDD settled net: cadence: Add architecture dependencies net: Start with correct mac_len in skb_network_protocol Revert "net: sctp: Fix a_rwnd/rwnd management to reflect real state of the receiver's buffer" cxgb4: Save the correct mac addr for hw-loopback connections in the L2T net: filter: seccomp: fix wrong decoding of BPF_S_ANC_SECCOMP_LD_W seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF qlcnic: Do not disable SR-IOV when VFs are assigned to VMs qlcnic: Fix QLogic application/driver interface for virtual NIC configuration qlcnic: Fix PVID configuration on eSwitch port. qlcnic: Fix max ring count calculation qlcnic: Fix to send INIT_NIC_FUNC as first mailbox. qlcnic: Fix panic due to uninitialzed delayed_work struct in use. ...
| | * | | | seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPFDaniel Borkmann2014-04-141-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linus reports that on 32-bit x86 Chromium throws the following seccomp resp. audit log messages: audit: type=1326 audit(1397359304.356:28108): auid=500 uid=500 gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023 pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=172 compat=0 ip=0xb2dd9852 code=0x30000 audit: type=1326 audit(1397359304.356:28109): auid=500 uid=500 gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023 pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=5 compat=0 ip=0xb2dd9852 code=0x50000 These audit messages are being triggered via audit_seccomp() through __secure_computing() in seccomp mode (BPF) filter with seccomp return codes 0x30000 (== SECCOMP_RET_TRAP) and 0x50000 (== SECCOMP_RET_ERRNO) during filter runtime. Moreover, Linus reports that x86_64 Chromium seems fine. The underlying issue that explains this is that the implementation of populate_seccomp_data() is wrong. Our seccomp data structure sd that is being shared with user ABI is: struct seccomp_data { int nr; __u32 arch; __u64 instruction_pointer; __u64 args[6]; }; Therefore, a simple cast to 'unsigned long *' for storing the value of the syscall argument via syscall_get_arguments() is just wrong as on 32-bit x86 (or any other 32bit arch), it would result in storing a0-a5 at wrong offsets in args[] member, and thus i) could leak stack memory to user space and ii) tampers with the logic of seccomp BPF programs that read out and check for syscall arguments: syscall_get_arguments(task, regs, 0, 1, (unsigned long *) &sd->args[0]); Tested on 32-bit x86 with Google Chrome, unfortunately only via remote test machine through slow ssh X forwarding, but it fixes the issue on my side. So fix it up by storing args in type correct variables, gcc is clever and optimizes the copy away in other cases, e.g. x86_64. Fixes: bd4cf0ed331a ("net: filter: rework/optimize internal BPF interpreter's instruction set") Reported-and-bisected-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Eric Paris <eparis@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | | user namespace: fix incorrect memory barriersMikulas Patocka2014-04-151-6/+5
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | smp_read_barrier_depends() can be used if there is data dependency between the readers - i.e. if the read operation after the barrier uses address that was obtained from the read operation before the barrier. In this file, there is only control dependency, no data dependecy, so the use of smp_read_barrier_depends() is incorrect. The code could fail in the following way: * the cpu predicts that idx < entries is true and starts executing the body of the for loop * the cpu fetches map->extent[0].first and map->extent[0].count * the cpu fetches map->nr_extents * the cpu verifies that idx < extents is true, so it commits the instructions in the body of the for loop The problem is that in this scenario, the cpu read map->extent[0].first and map->nr_extents in the wrong order. We need a full read memory barrier to prevent it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | cgroup: implement dynamic subtree controller enable/disable on the default ↵Tejun Heo2014-04-231-2/+365
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hierarchy cgroup is switching away from multiple hierarchies and will use one unified default hierarchy where controllers can be dynamically enabled and disabled per subtree. The default hierarchy will serve as the unified hierarchy to which all controllers are attached and a css on the default hierarchy would need to also serve the tasks of descendant cgroups which don't have the controller enabled - ie. the tree may be collapsed from leaf towards root when viewed from specific controllers. This has been implemented through effective css in the previous patches. This patch finally implements dynamic subtree controller enable/disable on the default hierarchy via a new knob - "cgroup.subtree_control" which controls which controllers are enabled on the child cgroups. Let's assume a hierarchy like the following. root - A - B - C \ D root's "cgroup.subtree_control" determines which controllers are enabled on A. A's on B. B's on C and D. This coincides with the fact that controllers on the immediate sub-level are used to distribute the resources of the parent. In fact, it's natural to assume that resource control knobs of a child belong to its parent. Enabling a controller in "cgroup.subtree_control" declares that distribution of the respective resources of the cgroup will be controlled. Note that this means that controller enable states are shared among siblings. The default hierarchy has an extra restriction - only cgroups which don't contain any task may have controllers enabled in "cgroup.subtree_control". Combined with the other properties of the default hierarchy, this guarantees that, from the view point of controllers, tasks are only on the leaf cgroups. In other words, only leaf csses may contain tasks. This rules out situations where child cgroups compete against internal tasks of the parent, which is a competition between two different types of entities without any clear way to determine resource distribution between the two. Different controllers handle it differently and all the implemented behaviors are ambiguous, ad-hoc, cumbersome and/or just wrong. Having this structural constraints imposed from cgroup core removes the burden from controller implementations and enables showing one consistent behavior across all controllers. When a controller is enabled or disabled, css associations for the controller in the subtrees of each child should be updated. After enabling, the whole subtree of a child should point to the new css of the child. After disabling, the whole subtree of a child should point to the cgroup's css. This is implemented by first updating cgroup states such that cgroup_e_css() result points to the appropriate css and then invoking cgroup_update_dfl_csses() which migrates all tasks in the affected subtrees to the self cgroup on the default hierarchy. * When read, "cgroup.subtree_control" lists all the currently enabled controllers on the children of the cgroup. * White-space separated list of controller names prefixed with either '+' or '-' can be written to "cgroup.subtree_control". The ones prefixed with '+' are enabled on the controller and '-' disabled. * A controller can be enabled iff the parent's "cgroup.subtree_control" enables it and disabled iff no child's "cgroup.subtree_control" has it enabled. * If a cgroup has tasks, no controller can be enabled via "cgroup.subtree_control". Likewise, if "cgroup.subtree_control" has some controllers enabled, tasks can't be migrated into the cgroup. * All controllers which aren't bound on other hierarchies are automatically associated with the root cgroup of the default hierarchy. All the controllers which are bound to the default hierarchy are listed in the read-only file "cgroup.controllers" in the root directory. * "cgroup.controllers" in all non-root cgroups is read-only file whose content is equal to that of "cgroup.subtree_control" of the parent. This indicates which controllers can be used in the cgroup's "cgroup.subtree_control". This is still experimental and there are some holes, one of which is that ->can_attach() failure during cgroup_update_dfl_csses() may leave the cgroups in an undefined state. The issues will be addressed by future patches. v2: Non-root cgroups now also have "cgroup.controllers". Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | | | | cgroup: prepare migration path for unified hierarchyTejun Heo2014-04-231-11/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unified hierarchy implementation would require re-migrating tasks onto the same cgroup on the default hierarchy to reflect updated effective csses. Update cgroup_migrate_prepare_dst() so that it accepts NULL as the destination cgrp. When NULL is specified, the destination is considered to be the cgroup on the default hierarchy associated with each css_set. After this change, the identity check in cgroup_migrate_add_src() isn't sufficient for noop detection as the associated csses may change without any cgroup association changing. The only way to tell whether a migration is noop or not is testing whether the source and destination csets are identical. The noop check in cgroup_migrate_add_src() is removed and cset identity test is added to cgroup_migreate_prepare_dst(). If it's detected that source and destination csets are identical, the cset is removed removed from @preloaded_csets and all the migration nodes are cleared which makes cgroup_migrate() ignore the cset. Also, make the function append the destination css_sets to @preloaded_list so that destination css_sets always come after source css_sets. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
* | | | | cgroup: update subsystem rebind restrictionsTejun Heo2014-04-231-7/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because the default root couldn't have any non-root csses attached to it, rebinding away from it was always allowed; however, the default hierarchy will soon host the unified hierarchy and have non-root csses so the rebind restrictions need to be updated accordingly. Instead of special casing rebinding from the default hierarchy and then checking whether the source hierarchy has children cgroups, which implies non-root csses for !dfl hierarchies, simply check whether the source hierarchy has non-root csses for the subsystem using css_next_child(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>