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2012-03-20Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq/core changes for v3.4 from Ingo Molnar * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Remove paranoid warnons and bogus fixups genirq: Flush the irq thread on synchronization genirq: Get rid of unnecessary IRQTF_DIED flag genirq: No need to check IRQTF_DIED before stopping a thread handler genirq: Get rid of unnecessary irqaction field in task_struct genirq: Fix incorrect check for forced IRQ thread handler softirq: Reduce invoke_softirq() code duplication genirq: Fix long-term regression in genirq irq_set_irq_type() handling x86-32/irq: Don't switch to irq stack for a user-mode irq
2012-03-20Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes for v3.4 from Ingo Molnar. The major features of this series are: - making RCU more aggressive about entering dyntick-idle mode in order to improve energy efficiency - converting a few more call_rcu()s to kfree_rcu()s - applying a number of rcutree fixes and cleanups to rcutiny - removing CONFIG_SMP #ifdefs from treercu - allowing RCU CPU stall times to be set via sysfs - adding CPU-stall capability to rcutorture - adding more RCU-abuse diagnostics - updating documentation - fixing yet more issues located by the still-ongoing top-to-bottom inspection of RCU, this time with a special focus on the CPU-hotplug code path. * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits) rcu: Stop spurious warnings from synchronize_sched_expedited rcu: Hold off RCU_FAST_NO_HZ after timer posted rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit() rcu: Remove redundant check for rcu_head misalignment PTR_ERR should be called before its argument is cleared. rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep rcu: Trace only after NULL-pointer check rcu: Call out dangers of expedited RCU primitives rcu: Rework detection of use of RCU by offline CPUs lockdep: Add CPU-idle/offline warning to lockdep-RCU splat rcu: No interrupt disabling for rcu_prepare_for_idle() rcu: Move synchronize_sched_expedited() to rcutree.c rcu: Check for illegal use of RCU from offlined CPUs rcu: Update stall-warning documentation rcu: Add CPU-stall capability to rcutorture rcu: Make documentation give more realistic rcutorture duration rcutorture: Permit holding off CPU-hotplug operations during boot rcu: Print scheduling-clock information on RCU CPU stall-warning messages ...
2012-03-14Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Been sitting on this for a while, but lets get this out the door. This fixes various important bugs for 3.3 final, along with a few more trivial ones. Please pull!" * 'for-linus' of git://git.kernel.dk/linux-block: block: fix ioc leak in put_io_context block, sx8: fix pointer math issue getting fw version Block: use a freezable workqueue for disk-event polling drivers/block/DAC960: fix -Wuninitialized warning drivers/block/DAC960: fix DAC960_V2_IOCTL_Opcode_T -Wenum-compare warning block: fix __blkdev_get and add_disk race condition block: Fix setting bio flags in drivers (sd_dif/floppy) block: Fix NULL pointer dereference in sd_revalidate_disk block: exit_io_context() should call elevator_exit_icq_fn() block: simplify ioc_release_fn() block: replace icq->changed with icq->flags
2012-03-13Merge branch 'linus' into irq/coreThomas Gleixner
Reason: Get upstream fixes integrated before further modifications. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Get rid of unnecessary irqaction field in task_structAlexander Gordeev
When a new thread handler is created, an irqaction is passed to it as data. Not only that irqaction is stored in task_struct by the handler for later use, but also a structure associated with the kernel thread keeps this value as long as the thread exists. This fix kicks irqaction out off task_struct. Yes, I introduce new bit field. But it allows not only to eliminate the duplicate, but also shortens size of task_struct. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135925.GB2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-08Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
Pull minor devicetree bug fixes and documentation updates from Grant Likely: "Fixes up a duplicate #include, adds an empty implementation of of_find_compatible_node() and make git ignore .dtb files. And fix up bus name on OF described PHYs. Nothing exciting here." * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6: doc: dt: Fix broken reference in gpio-leds documentation of/mdio: fix fixed link bus name of/fdt.c: asm/setup.h included twice of: add picochip vendor prefix dt: add empty of_find_compatible_node function ARM: devicetree: Add .dtb files to arch/arm/boot/.gitignore
2012-03-07Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King. * 'fixes' of git://git.linaro.org/people/rmk/linux-arm: ARM: 7358/1: perf: add PMU hotplug notifier ARM: 7357/1: perf: fix overflow handling for xscale2 PMUs ARM: 7356/1: perf: check that we have an event in the PMU IRQ handlers ARM: 7355/1: perf: clear overflow flag when disabling counter on ARMv7 PMU ARM: 7354/1: perf: limit sample_period to half max_period in non-sampling mode ARM: ecard: ensure fake vma vm_flags is setup ARM: 7346/1: errata: fix PL310 erratum #753970 workaround selection ARM: 7345/1: errata: update workaround for A9 erratum #743622 ARM: 7348/1: arm/spear600: fix one-shot timer ARM: 7339/1: amba/serial.h: Include types.h for resolving dependency of type bool
2012-03-05Merge branch 'akpm' (Andrew's patch bomb)Linus Torvalds
Merge the emailed seties of 19 patches from Andrew Morton * akpm: rapidio/tsi721: fix queue wrapping bug in inbound doorbell handler memcg: fix mapcount check in move charge code for anonymous page mm: thp: fix BUG on mm->nr_ptes alpha: fix 32/64-bit bug in futex support memcg: fix GPF when cgroup removal races with last exit debugobjects: Fix selftest for static warnings floppy/scsi: fix setting of BIO flags memcg: fix deadlock by inverting lrucare nesting drivers/rtc/rtc-r9701.c: fix crash in r9701_remove() c2port: class_create() returns an ERR_PTR pps: class_create() returns an ERR_PTR, not NULL hung_task: fix the broken rcu_lock_break() logic vfork: kill PF_STARTING coredump_wait: don't call complete_vfork_done() vfork: make it killable vfork: introduce complete_vfork_done() aio: wake up waiters when freeing unused kiocbs kprobes: return proper error code from register_kprobe() kmsg_dump: don't run on non-error paths by default
2012-03-05memcg: fix GPF when cgroup removal races with last exitHugh Dickins
When moving tasks from old memcg (with move_charge_at_immigrate on new memcg), followed by removal of old memcg, hit General Protection Fault in mem_cgroup_lru_del_list() (called from release_pages called from free_pages_and_swap_cache from tlb_flush_mmu from tlb_finish_mmu from exit_mmap from mmput from exit_mm from do_exit). Somewhat reproducible, takes a few hours: the old struct mem_cgroup has been freed and poisoned by SLAB_DEBUG, but mem_cgroup_lru_del_list() is still trying to update its stats, and take page off lru before freeing. A task, or a charge, or a page on lru: each secures a memcg against removal. In this case, the last task has been moved out of the old memcg, and it is exiting: anonymous pages are uncharged one by one from the memcg, as they are zapped from its pagetables, so the charge gets down to 0; but the pages themselves are queued in an mmu_gather for freeing. Most of those pages will be on lru (and force_empty is careful to lru_add_drain_all, to add pages from pagevec to lru first), but not necessarily all: perhaps some have been isolated for page reclaim, perhaps some isolated for other reasons. So, force_empty may find no task, no charge and no page on lru, and let the removal proceed. There would still be no problem if these pages were immediately freed; but typically (and the put_page_testzero protocol demands it) they have to be added back to lru before they are found freeable, then removed from lru and freed. We don't see the issue when adding, because the mem_cgroup_iter() loops keep their own reference to the memcg being scanned; but when it comes to mem_cgroup_lru_del_list(). I believe this was not an issue in v3.2: there, PageCgroupAcctLRU and PageCgroupUsed flags were used (like a trick with mirrors) to deflect view of pc->mem_cgroup to the stable root_mem_cgroup when neither set. 38c5d72f3ebe ("memcg: simplify LRU handling by new rule") mercifully removed those convolutions, but left this General Protection Fault. But it's surprisingly easy to restore the old behaviour: just check PageCgroupUsed in mem_cgroup_lru_add_list() (which decides on which lruvec to add), and reset pc to root_mem_cgroup if page is uncharged. A risky change? just going back to how it worked before; testing, and an audit of uses of pc->mem_cgroup, show no problem. And there's a nice bonus: with mem_cgroup_lru_add_list() itself making sure that an uncharged page goes to root lru, mem_cgroup_reset_owner() no longer has any purpose, and we can safely revert 4e5f01c2b9b9 ("memcg: clear pc->mem_cgroup if necessary"). Calling update_page_reclaim_stat() after add_page_to_lru_list() in swap.c is not strictly necessary: the lru_lock there, with RCU before memcg structures are freed, makes mem_cgroup_get_reclaim_stat_from_page safe without that; but it seems cleaner to rely on one dependency less. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: kill PF_STARTINGOleg Nesterov
Previously it was (ab)used by utrace. Then it was wrongly used by the scheduler code. Currently it is not used, kill it before it finds the new erroneous user. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05coredump_wait: don't call complete_vfork_done()Oleg Nesterov
Now that CLONE_VFORK is killable, coredump_wait() no longer needs complete_vfork_done(). zap_threads() should find and kill all tasks with the same ->mm, this includes our parent if ->vfork_done is set. mm_release() becomes the only caller, unexport complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: make it killableOleg Nesterov
Make vfork() killable. Change do_fork(CLONE_VFORK) to do wait_for_completion_killable(). If it fails we do not return to the user-mode and never touch the memory shared with our child. However, in this case we should clear child->vfork_done before return, we use task_lock() in do_fork()->wait_for_vfork_done() and complete_vfork_done() to serialize with each other. Note: now that we use task_lock() we don't really need completion, we could turn task->vfork_done into "task_struct *wake_up_me" but this needs some complications. NOTE: this and the next patches do not affect in-kernel users of CLONE_VFORK, kernel threads run with all signals ignored including SIGKILL/SIGSTOP. However this is obviously the user-visible change. Not only a fatal signal can kill the vforking parent, a sub-thread can do execve or exit_group() and kill the thread sleeping in vfork(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: introduce complete_vfork_done()Oleg Nesterov
No functional changes. Move the clear-and-complete-vfork_done code into the new trivial helper, complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05kmsg_dump: don't run on non-error paths by defaultMatthew Garrett
Since commit 04c6862c055f ("kmsg_dump: add kmsg_dump() calls to the reboot, halt, poweroff and emergency_restart paths"), kmsg_dump() gets run on normal paths including poweroff and reboot. This is less than ideal given pstore implementations that can only represent single backtraces, since a reboot may overwrite a stored oops before it's been picked up by userspace. In addition, some pstore backends may have low performance and provide a significant delay in reboot as a result. This patch adds a printk.always_kmsg_dump kernel parameter (which can also be changed from userspace). Without it, the code will only be run on failure paths rather than on normal paths. The option can be enabled in environments where there's a desire to attempt to audit whether or not a reboot was cleanly requested or not. Signed-off-by: Matthew Garrett <mjg@redhat.com> Acked-by: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Don Zickus <dzickus@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) TCP SACK processing can calculate an incorrect reordering value in some cases, fix from Neal Cardwell. 2) tcp_mark_head_lost() can split SKBs in situations where it should not, violating send queue invariants expected by other pieces of code and thus resulting (eventually) in corrupted retransmit state counters. Also from Neal Cardwell. 3) qla3xxx erroneously calls spin_lock_irqrestore() with constant hw_flags of zero. Fix from Santosh Nayak. 4) Fix NULL deref in rt2x00, from Gabor Juhos. 5) pch_gbe passes address of wrong typed object to pch_gbe_validate_option thus corrupting part of the value. From Dan Carpenter. 6) We must check the return value of nlmsg_parse() before trying to use the results. From Eric Dumazet. 7) Bridging code fails to check return value of ipv6_dev_get_saddr() thus potentially leaving uninitialized garbage in the outgoing ipv6 header. From Ulrich Weber. 8) Due to rounding and a reversed operation on jiffies, bridge message ages can go backwards instead of forwards, thus breaking STP. Fixes from Joakim Tjernlund. 9) r8169 modifies Config* registers without properly holding the Config9346 lock, resulting in corrupted IP fragments on some chips. Fix from Francois Romieu. 10) NET_PACKET_ENGINE default wan't set properly during the network driver mega-move. Fix from Stephen Hemminger. 11) vmxnet3 uses TCP header size where it actually should use the UDP header size, fix from Shreyas Bhatewara. 12) Netfilter bridge module autoload is busted in the compat case, fix from Florian Westphal. 13) Wireless Key removal was not setting multicast bits correctly thus accidently killing the unicast key 0 and thus all traffic stops. Fix from Johannes Berg. 14) Fix endless retries of A-MPDU transmissions in brcm80211 driver. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (22 commits) qla3xxx: ethernet: Fix bogus interrupt state flag. bridge: check return value of ipv6_dev_get_saddr() rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo() bridge: message age needs to increase, not decrease. bridge: Adjust min age inc for HZ > 256 tcp: don't fragment SACKed skbs in tcp_mark_head_lost() r8169: corrupted IP fragments fix for large mtu. packetengines: fix config default vmxnet3: Fix transport header size enic: fix an endian bug in enic_probe() pch_gbe: memory corruption calling pch_gbe_validate_option() tg3: Fix tg3_get_stats64 for 5700 / 5701 devs tcp: fix false reordering signal in tcp_shifted_skb tcp: fix comment for tp->highest_sack netfilter: bridge: fix module autoload in compat case brcm80211: smac: only print block-ack timeout message at trace level brcm80211: smac: fix endless retry of A-MPDU transmissions mac80211: Fix a warning on changing to monitor mode from STA mac80211: zero initialize count field in ieee80211_tx_rate iwlwifi: fix key removal ...
2012-03-05Merge branch 'for-3.3-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull per-cpu patches from Tejun Heo: "This pull request contains four patches. One replaces manual clearing with bitmap_clear(), two fix generic definition of __this_cpu ops so that they don't choose unnecessarily strict arch version. One makes _this_cpu definition use raw_local_irq_*() so that it doesn't end up wrecking irq on/off state tracking when used from inside lockdep. Of the four patches, the raw_local_irq_*() update is the most important, so please feel free to cherry pick only that one patch and ignore the rest if you want to - commit e920d5971d 'percpu: use raw_local_irq_* in _this_cpu op'." * 'for-3.3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu: fix __this_cpu_{sub,inc,dec}_return() definition percpu: use raw_local_irq_* in _this_cpu op percpu: fix generic definition of __this_cpu_add_and_return() percpu: use bitmap_clear
2012-03-04vfs: move dentry_cmp from <linux/dcache.h> to fs/dcache.cLinus Torvalds
It's only used inside fs/dcache.c, and we're going to play games with it for the word-at-a-time patches. This time we really don't even want to export it, because it really is an internal function to fs/dcache.c, and has been since it was introduced. Having it in that extremely hot header file (it's included in pretty much everything, thanks to <linux/fs.h>) is a disaster for testing different versions, and is utterly pointless. We really should have some kind of header file diet thing, where we figure out which parts of header files are really better off private and only result in more expensive compiles. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-04percpu: fix __this_cpu_{sub,inc,dec}_return() definitionKonstantin Khlebnikov
This patch adds missed "__" prefixes, otherwise these functions works as irq/preemption safe. Reported-by: Torsten Kaiser <just.for.lkml@googlemail.com> Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-03-02vfs: clarify and clean up dentry_cmp()Linus Torvalds
It did some odd things for unclear reasons. As this is one of the functions that gets changed when doing word-at-a-time compares, this is yet another of the "don't change any semantics, but clean things up so that subsequent patches don't get obscured by the cleanups". Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02vfs: uninline full_name_hash()Linus Torvalds
.. and also use it in lookup_one_len() rather than open-coding it. There aren't any performance-critical users, so inlining it is silly. But it wouldn't matter if it wasn't for the fact that the word-at-a-time dentry name patches want to conditionally replace the function, and uninlining it sets the stage for that. So again, this is a preparatory patch that doesn't change any semantics, and only prepares for a much cleaner and testable word-at-a-time dentry name accessor patch. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02vfs: trivial __d_lookup_rcu() cleanupsLinus Torvalds
These don't change any semantics, but they clean up the code a bit and mark some arguments appropriately 'const'. They came up as I was doing the word-at-a-time dcache name accessor code, and cleaning this up now allows me to send out a smaller relevant interesting patch for the experimental stuff. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02regset: Return -EFAULT, not -EIO, on host-side memory faultH. Peter Anvin
There is only one error code to return for a bad user-space buffer pointer passed to a system call in the same address space as the system call is executed, and that is EFAULT. Furthermore, the low-level access routines, which catch most of the faults, return EFAULT already. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@hack.frob.com> Cc: <stable@vger.kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02regset: Prevent null pointer reference on readonly regsetsH. Peter Anvin
The regset common infrastructure assumed that regsets would always have .get and .set methods, but not necessarily .active methods. Unfortunately people have since written regsets without .set methods. Rather than putting in stub functions everywhere, handle regsets with null .get or .set methods explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@hack.frob.com> Cc: <stable@vger.kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02Block: use a freezable workqueue for disk-event pollingAlan Stern
This patch (as1519) fixes a bug in the block layer's disk-events polling. The polling is done by a work routine queued on the system_nrt_wq workqueue. Since that workqueue isn't freezable, the polling continues even in the middle of a system sleep transition. Obviously, polling a suspended drive for media changes and such isn't a good thing to do; in the case of USB mass-storage devices it can lead to real problems requiring device resets and even re-enumeration. The patch fixes things by creating a new system-wide, non-reentrant, freezable workqueue and using it for disk-events polling. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: <stable@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-02block: Fix NULL pointer dereference in sd_revalidate_diskJun'ichi Nomura
Since 2.6.39 (1196f8b), when a driver returns -ENOMEDIUM for open(), __blkdev_get() calls rescan_partitions() to remove in-kernel partition structures and raise KOBJ_CHANGE uevent. However it ends up calling driver's revalidate_disk without open and could cause oops. In the case of SCSI: process A process B ---------------------------------------------- sys_open __blkdev_get sd_open returns -ENOMEDIUM scsi_remove_device <scsi_device torn down> rescan_partitions sd_revalidate_disk <oops> Oopses are reported here: http://marc.info/?l=linux-scsi&m=132388619710052 This patch separates the partition invalidation from rescan_partitions() and use it for -ENOMEDIUM case. Reported-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-28tcp: fix comment for tp->highest_sackNeal Cardwell
There was an off-by-one error in the comments describing the highest_sack field in struct tcp_sock. The comments previously claimed that it was the "start sequence of the highest skb with SACKed bit". This commit fixes the comments to note that it is the "start sequence of the skb just *after* the highest skb with SACKed bit". Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-28Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu The major features of this series are: - making RCU more aggressive about entering dyntick-idle mode in order to improve energy efficiency - converting a few more call_rcu()s to kfree_rcu()s - applying a number of rcutree fixes and cleanups to rcutiny - removing CONFIG_SMP #ifdefs from treercu - allowing RCU CPU stall times to be set via sysfs - adding CPU-stall capability to rcutorture - adding more RCU-abuse diagnostics - updating documentation - fixing yet more issues located by the still-ongoing top-to-bottom inspection of RCU, this time with a special focus on the CPU-hotplug code path. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-27Merge branch 'fixes-for-grant' of git://sources.calxeda.com/kernel/linux ↵Grant Likely
into devicetree/merge
2012-02-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
1) ICMP sockets leave err uninitialized but we try to return it for the unsupported MSG_OOB case, reported by Dave Jones. 2) Add new Zaurus device ID entries, from Dave Jones. 3) Pointer calculation in hso driver memset is wrong, from Dan Carpenter. 4) ks8851_probe() checks unsigned value as negative, fix also from Dan Carpenter. 5) Fix crashes in atl1c driver due to TX queue handling, from Eric Dumazet. I anticipate some TX side locking fixes coming in the near future for this driver as well. 6) The inline directive fix in Bluetooth which was breaking the build only with very new versions of GCC, from Johan Hedberg. 7) Fix crashes in the ATP CLIP code due to ARP cleanups this merge window, reported by Meelis Roos and fixed by Eric Dumazet. 8) JME driver doesn't flush RX FIFO correctly, from Guo-Fu Tseng. 9) Some ip6_route_output() callers test the return value for NULL, but this never happens as the convention is to return a dst entry with dst->error set. Fixes from RonQing Li. 10) Logitech Harmony 900 should be handled by zaurus driver not cdc_ether, update white lists and black lists accordingly. From Scott Talbert. 11) Receiving from certain kinds of devices there won't be a MAC header, so there is no MAC header to fixup in the IPSEC code, and if we try to do it we'll crash. Fix from Eric Dumazet. 12) Port type array indexing off-by-one in mlx4 driver, fix from Yevgeny Petrilin. 13) Fix regression in link-down handling in davinci_emac which causes all RX descriptors to be freed up and therefore RX to wedge completely, from Christian Riesch. 14) It took two attempts, but ctnetlink soft lockups seem to be cured now, from Pablo Neira Ayuso. 15) Endianness bug fix in ENIC driver, from Santosh Nayak. 16) The long ago conversion of the PPP fragmentation code over to abstracted SKB list handling wasn't perfect, once we get an out of sequence SKB we don't flush the rest of them like we should. From Ben McKeegan. 17) Fix regression of ->ip_summed initialization in sfc driver. From Ben Hutchings. 18) Bluetooth timeout mistakenly using msecs instead of jiffies, from Andrzej Kaczmarek. 19) Using _sync variant of work cancellation results in deadlocks, use the non _sync variants instead. From Andre Guedes. 20) Bluetooth rfcomm code had reference counting problems leading to crashes, fix from Octavian Purdila. 21) The conversion of netem over to classful qdisc handling added two bugs to netem_dequeue(), fixes from Eric Dumazet. 22) Missing pci_iounmap() in ATM Solos driver. Fix from Julia Lawall. 23) b44_pci_exit() should not have __exit tag since it's invoked from non-__exit code. From Nikola Pajkovsky. 24) The conversion of the neighbour hash tables over to RCU added a race, fixed here by adding the necessary reread of tbl->nht, fix from Michel Machado. 25) When we added VF (virtual function) attributes for network device dumps, this potentially bloats up the size of the dump of one network device such that the dump size is too large for the buffer allocated by properly written netlink applications. In particular, if you add 255 VFs to a network device, parts of GLIBC stop working. To fix this, we add an attribute that is used to turn on these extended portions of the network device dump. Sophisticaed applications like 'ip' that want to see this stuff will be changed to set the attribute, whereas things like GLIBC that don't care about VFs simply will not, and therefore won't be busted by the mere presence of VFs on a network device. Thanks to the tireless work of Greg Rose on this fix. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (53 commits) sfc: Fix assignment of ip_summed for pre-allocated skbs ppp: fix 'ppp_mp_reconstruct bad seq' errors enic: Fix endianness bug. gre: fix spelling in comments netfilter: ctnetlink: fix soft lockup when netlink adds new entries (v2) Revert "netfilter: ctnetlink: fix soft lockup when netlink adds new entries" davinci_emac: Do not free all rx dma descriptors during init mlx4_core: Fixing array indexes when setting port types phy: IC+101G and PHY_HAS_INTERRUPT flag netdev/phy/icplus: Correct broken phy_init code ipsec: be careful of non existing mac headers Move Logitech Harmony 900 from cdc_ether to zaurus hso: memsetting wrong data in hso_get_count() netfilter: ip6_route_output() never returns NULL. ethernet/broadcom: ip6_route_output() never returns NULL. ipv6: ip6_route_output() never returns NULL. jme: Fix FIFO flush issue atm: clip: remove clip_tbl ipv4: ping: Fix recvmsg MSG_OOB error handling. rtnetlink: Fix problem with buffer allocation ...
2012-02-26Fix autofs compile without CONFIG_COMPATLinus Torvalds
The autofs compat handling fix caused a compile failure when CONFIG_COMPAT isn't defined. Instead of adding random #ifdef'fery in autofs, let's just make the compat helpers earlier to use: without CONFIG_COMPAT, is_compat_task() just hardcodes to zero. We could probably do something similar for a number of other cases where we have #ifdef's in code, but this is the low-hanging fruit. Reported-and-tested-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-24epoll: introduce POLLFREE to flush ->signalfd_wqh before kfree()Oleg Nesterov
This patch is intentionally incomplete to simplify the review. It ignores ep_unregister_pollwait() which plays with the same wqh. See the next change. epoll assumes that the EPOLL_CTL_ADD'ed file controls everything f_op->poll() needs. In particular it assumes that the wait queue can't go away until eventpoll_release(). This is not true in case of signalfd, the task which does EPOLL_CTL_ADD uses its ->sighand which is not connected to the file. This patch adds the special event, POLLFREE, currently only for epoll. It expects that init_poll_funcptr()'ed hook should do the necessary cleanup. Perhaps it should be defined as EPOLLFREE in eventpoll. __cleanup_sighand() is changed to do wake_up_poll(POLLFREE) if ->signalfd_wqh is not empty, we add the new signalfd_cleanup() helper. ep_poll_callback(POLLFREE) simply does list_del_init(task_list). This make this poll entry inconsistent, but we don't care. If you share epoll fd which contains our sigfd with another process you should blame yourself. signalfd is "really special". I simply do not know how we can define the "right" semantics if it used with epoll. The main problem is, epoll calls signalfd_poll() once to establish the connection with the wait queue, after that signalfd_poll(NULL) returns the different/inconsistent results depending on who does EPOLL_CTL_MOD/signalfd_read/etc. IOW: apart from sigmask, signalfd has nothing to do with the file, it works with the current thread. In short: this patch is the hack which tries to fix the symptoms. It also assumes that nobody can take tasklist_lock under epoll locks, this seems to be true. Note: - we do not have wake_up_all_poll() but wake_up_poll() is fine, poll/epoll doesn't use WQ_FLAG_EXCLUSIVE. - signalfd_cleanup() uses POLLHUP along with POLLFREE, we need a couple of simple changes in eventpoll.c to make sure it can't be "lost". Reported-by: Maxime Bizon <mbizon@freebox.fr> Cc: <stable@kernel.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-23ARM: 7339/1: amba/serial.h: Include types.h for resolving dependency of type ↵viresh kumar
bool serial.h uses bool, but its definition is missing, as it doesn't include types.h. Fix this by including types.h Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-23ipsec: be careful of non existing mac headersEric Dumazet
Niccolo Belli reported ipsec crashes in case we handle a frame without mac header (atm in his case) Before copying mac header, better make sure it is present. Bugzilla reference: https://bugzilla.kernel.org/show_bug.cgi?id=42809 Reported-by: Niccolò Belli <darkbasic@linuxsystems.it> Tested-by: Niccolò Belli <darkbasic@linuxsystems.it> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-23Merge branch 'nf' of git://1984.lsi.us.es/netDavid S. Miller
2012-02-22Merge tag 'usb-3.3-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb USB bugfixes for 3.3-rc4 A number of new device ids, and a cleanup/fix for some of the option device ids that shouldn't have been added in the first place. There's also a few USB 3 fixes for problems that people have reported, and a usb-storage bugfix to round it out. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> * tag 'usb-3.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: USB: Added Kamstrup VID/PIDs to cp210x serial driver. USB: Serial: ti_usb_3410_5052: Add Abbot Diabetes Care cable id usb-storage: fix freezing of the scanning thread xhci: Fix encoding for HS bulk/control NAK rate. USB: Set hub depth after USB3 hub reset USB: Fix handoff when BIOS disables host PCI device. USB: option: cleanup zte 3g-dongle's pid in option.c USB: Don't fail USB3 probe on missing legacy PCI IRQ. xhci: Fix oops caused by more USB2 ports than USB3 ports. USB: Remove duplicate USB 3.0 hub feature #defines.
2012-02-22Merge tag 'nfs-for-3.3-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Bugfixes for the NFS client. Fix a nasty Oops in the NFSv4 getacl code, another source of infinite loops in the NFSv4 state recovery code, and a regression in NFSv4.1 session initialisation. Also deal with an NFSv4.1 memory leak. * tag 'nfs-for-3.3-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFSv4: fix server_scope memory leak NFSv4.1: Fix a NFSv4.1 session initialisation regression NFSv4: Ensure we throw out bad delegation stateids on NFS4ERR_BAD_STATEID NFSv4: Fix an Oops in the NFSv4 getacl code
2012-02-21sys_poll: fix incorrect type for 'timeout' parameterLinus Torvalds
The 'poll()' system call timeout parameter is supposed to be 'int', not 'long'. Now, the reason this matters is that right now 32-bit compat mode is broken on at least x86-64, because the 32-bit code just calls 'sys_poll()' directly on x86-64, and the 32-bit argument will have been zero-extended, turning a signed 'int' into a large unsigned 'long' value. We could just introduce a 'compat_sys_poll()' function for this, and that may eventually be what we have to do, but since the actual standard poll() semantics is *supposed* to be 'int', and since at least on x86-64 glibc sign-extends the argument before invocing the system call (so nobody can actually use a 64-bit timeout value in user space _anyway_, even in 64-bit binaries), the simpler solution would seem to be to just fix the definition of the system call to match what it should have been from the very start. If it turns out that somebody somehow circumvents the user-level libc 64-bit sign extension and actually uses a large unsigned 64-bit timeout despite that not being how poll() is supposed to work, we will need to do the compat_sys_poll() approach. Reported-by: Thomas Meyer <thomas@m3y3r.de> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-21rtnetlink: Fix problem with buffer allocationGreg Rose
Implement a new netlink attribute type IFLA_EXT_MASK. The mask is a 32 bit value that can be used to indicate to the kernel that certain extended ifinfo values are requested by the user application. At this time the only mask value defined is RTEXT_FILTER_VF to indicate that the user wants the ifinfo dump to send information about the VFs belonging to the interface. This patch fixes a bug in which certain applications do not have large enough buffers to accommodate the extra information returned by the kernel with large numbers of SR-IOV virtual functions. Those applications will not send the new netlink attribute with the interface info dump request netlink messages so they will not get unexpectedly large request buffers returned by the kernel. Modifies the rtnl_calcit function to traverse the list of net devices and compute the minimum buffer size that can hold the info dumps of all matching devices based upon the filter passed in via the new netlink attribute filter mask. If no filter mask is sent then the buffer allocation defaults to NLMSG_GOODSIZE. With this change it is possible to add yet to be defined netlink attributes to the dump request which should make it fairly extensible in the future. Signed-off-by: Greg Rose <gregory.v.rose@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-21percpu: use raw_local_irq_* in _this_cpu opMing Lei
It doesn't make sense to trace irq off or do irq flags lock proving inside 'this_cpu' operations, so replace local_irq_* with raw_local_irq_* in 'this_cpu' op. Also the patch fixes onelockdep warning[1] by the replacement, see below: In commit: 933393f58fef9963eac61db8093689544e29a600(percpu: Remove irqsafe_cpu_xxx variants), local_irq_save/restore(flags) are added inside this_cpu_inc operation, so that trace_hardirqs_off_caller will be called by trace_hardirqs_on_caller directly because __debug_atomic_inc is implemented as this_cpu_inc, which may trigger the lockdep warning[1], for example in the below ARM scenary: kernel_thread_helper /*irq disabled*/ ->trace_hardirqs_on_caller /*hardirqs_enabled was set*/ ->trace_hardirqs_off_caller /*hardirqs_enabled cleared*/ __this_cpu_add(redundant_hardirqs_on) ->trace_hardirqs_off_caller /*irq disabled, so call here*/ The 'unannotated irqs-on' warning will be triggered somewhere because irq is just enabled after the irq trace in kernel_thread_helper. [1], [ 0.162841] ------------[ cut here ]------------ [ 0.167694] WARNING: at kernel/lockdep.c:3493 check_flags+0xc0/0x1d0() [ 0.174468] Modules linked in: [ 0.177703] Backtrace: [ 0.180328] [<c00171f0>] (dump_backtrace+0x0/0x110) from [<c0412320>] (dump_stack+0x18/0x1c) [ 0.189086] r6:c051f778 r5:00000da5 r4:00000000 r3:60000093 [ 0.195007] [<c0412308>] (dump_stack+0x0/0x1c) from [<c00410e8>] (warn_slowpath_common+0x54/0x6c) [ 0.204223] [<c0041094>] (warn_slowpath_common+0x0/0x6c) from [<c0041124>] (warn_slowpath_null+0x24/0x2c) [ 0.214111] r8:00000000 r7:00000000 r6:ee069598 r5:60000013 r4:ee082000 [ 0.220825] r3:00000009 [ 0.223693] [<c0041100>] (warn_slowpath_null+0x0/0x2c) from [<c0088f38>] (check_flags+0xc0/0x1d0) [ 0.232910] [<c0088e78>] (check_flags+0x0/0x1d0) from [<c008d348>] (lock_acquire+0x4c/0x11c) [ 0.241668] [<c008d2fc>] (lock_acquire+0x0/0x11c) from [<c0415aa4>] (_raw_spin_lock+0x3c/0x74) [ 0.250610] [<c0415a68>] (_raw_spin_lock+0x0/0x74) from [<c010a844>] (set_task_comm+0x20/0xc0) [ 0.259521] r6:ee069588 r5:ee0691c0 r4:ee082000 [ 0.264404] [<c010a824>] (set_task_comm+0x0/0xc0) from [<c0060780>] (kthreadd+0x28/0x108) [ 0.272857] r8:00000000 r7:00000013 r6:c0044a08 r5:ee0691c0 r4:ee082000 [ 0.279571] r3:ee083fe0 [ 0.282470] [<c0060758>] (kthreadd+0x0/0x108) from [<c0044a08>] (do_exit+0x0/0x6dc) [ 0.290405] r5:c0060758 r4:00000000 [ 0.294189] ---[ end trace 1b75b31a2719ed1c ]--- [ 0.299041] possible reason: unannotated irqs-on. [ 0.303955] irq event stamp: 5 [ 0.307159] hardirqs last enabled at (4): [<c001331c>] no_work_pending+0x8/0x2c [ 0.314880] hardirqs last disabled at (5): [<c0089b08>] trace_hardirqs_on_caller+0x60/0x26c [ 0.323547] softirqs last enabled at (0): [<c003f754>] copy_process+0x33c/0xef4 [ 0.331207] softirqs last disabled at (0): [< (null)>] (null) [ 0.337585] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000 Acked-by: Christoph Lameter <cl@linux.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-02-21rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sectionsPaul E. McKenney
RCU, RCU-bh, and RCU-sched read-side critical sections are forbidden in the inner idle loop, that is, between the rcu_idle_enter() and the rcu_idle_exit() -- RCU will happily ignore any such read-side critical sections. However, things like powertop need tracepoints in the inner idle loop. This commit therefore provides an RCU_NONIDLE() macro that can be used to wrap code in the idle loop that requires RCU read-side critical sections. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
2012-02-21rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdepHeiko Carstens
The WARN_ON_ONCE() in rcu_lock_acquire() results in infinite recursion on S390, and also doesn't print very much information. Remove this. Updated patch to add lockdep-RCU assertions to RCU's read-side primitives. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Call out dangers of expedited RCU primitivesPaul E. McKenney
The expedited RCU primitives can be quite useful, but they have some high costs as well. This commit updates and creates docbook comments calling out the costs, and updates the RCU documentation as well. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Check for illegal use of RCU from offlined CPUsPaul E. McKenney
Although it is legal to use RCU during early boot, it is anything but legal to use RCU at runtime from an offlined CPU. After all, RCU explicitly ignores offlined CPUs. This commit therefore adds checks for runtime use of RCU from offlined CPUs. These checks are not perfect, in particular, they can be subverted through use of things like rcu_dereference_raw(). Note that it is not possible to put checks in rcu_read_lock() and friends due to the fact that these primitives are used in code that might be used under either RCU or lock-based protection, which means that checking rcu_read_lock() gets you fat piles of false positives. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Note that rcu_access_pointer() can be used for teardownPaul E. McKenney
There is no convenient expression for rcu_deference_protected() when it is used in tearing down multilinked structures following a grace period. For example, suppose that an element containing an RCU-protected pointer to a second element is removed from an enclosing RCU-protected data structure, then the write-side lock is released, and finally synchronize_rcu() is invoked to wait for a grace period. Then it is necessary to traverse the pointer in order to free up the second element. But we are not in an RCU read-side critical section and we are holding no locks, so the usual rcu_dereference_check() and rcu_dereference_protected() primitives are not appropriate. Neither is rcu_dereference_raw(), as it is intended for use in data structures where the user defines the locking design (for example, list_head). So this responsibility is added to rcu_access_pointer()'s list, and this commit updates rcu_assign_pointer()'s header comment accordingly. Suggested-by: David Howells <dhowells@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: David Howells <dhowells@redhat.com>
2012-02-21rcu: Make rcu_sleep_check() also check rcu_lock_mapPaul E. McKenney
Although it is OK to be preempted in an RCU read-side critical section for TREE_PREEMPT_RCU, it is definitely not OK to be preempted, block, or might_sleep() within an RCU read-side critical section for TREE_RCU. Unfortunately, rcu_might_sleep() currently only checks for RCU-bh and RCU-sched read-side critical sections. This commit therefore makes rcu_might_sleep() check for RCU read-side critical sections, but only in TREE_RCU builds. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Simplify unboosting checksPaul E. McKenney
This is a port of commit #82e78d80 from TREE_PREEMPT_RCU to TINY_PREEMPT_RCU. This commit uses the fact that current->rcu_boost_mutex is set any time that the RCU_READ_UNLOCK_BOOSTED flag is set in the current->rcu_read_unlock_special bitmask. This allows tests of the bit to be changed to tests of the pointer, which in turn allows the RCU_READ_UNLOCK_BOOSTED flag to be eliminated. Please note that the check of current->rcu_read_unlock_special need not change because any time that RCU_READ_UNLOCK_BOOSTED was set, so was RCU_READ_UNLOCK_BLOCKED. Therefore, __rcu_read_unlock() can continue testing current->rcu_read_unlock_special for non-zero, as before. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Prevent RCU callbacks from executing before scheduler initializedPaul E. McKenney
This is a port of commit #b0d3041 from TREE_RCU to TREE_PREEMPT_RCU. Under some rare but real combinations of configuration parameters, RCU callbacks are posted during early boot that use kernel facilities that are not yet initialized. Therefore, when these callbacks are invoked, hard hangs and crashes ensue. This commit therefore prevents RCU callbacks from being invoked until after the scheduler is fully up and running, as in after multiple tasks have been spawned. It might well turn out that a better approach is to identify the specific RCU callbacks that are causing this problem, but that discussion will wait until such time as someone really needs an RCU callback to be invoked (as opposed to merely registered) during early boot. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Avoid waking up CPUs having only kfree_rcu() callbacksPaul E. McKenney
When CONFIG_RCU_FAST_NO_HZ is enabled, RCU will allow a given CPU to enter dyntick-idle mode even if it still has RCU callbacks queued. RCU avoids system hangs in this case by scheduling a timer for several jiffies in the future. However, if all of the callbacks on that CPU are from kfree_rcu(), there is no reason to wake the CPU up, as it is not a problem to defer freeing of memory. This commit therefore tracks the number of callbacks on a given CPU that are from kfree_rcu(), and avoids scheduling the timer if all of a given CPU's callbacks are from kfree_rcu(). Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21rcu: Improve synchronize_rcu() diagnosticsFrederic Weisbecker
Although TREE_PREEMPT_RCU indirectly uses might_sleep() to detect illegal use of synchronize_sched() and synchronize_rcu_bh() from within an RCU read-side critical section, this might_sleep() check is bypassed when there is only a single CPU (for example, when running an SMP kernel on a single-CPU system). This patch therefore adds a might_sleep() call to the rcu_blocking_is_gp() check that is unconditionally invoked from both synchronize_sched() and synchronize_rcu_bh(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21percpu: fix generic definition of __this_cpu_add_and_return()Konstantin Khlebnikov
This patch adds missed "__" into function prefix. Otherwise on all archectures (except x86) it expands to irq/preemtion-safe variant: _this_cpu_generic_add_return(), which do extra irq-save/irq-restore. Optimal generic implementation is __this_cpu_generic_add_return(). Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>