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* rcu: remove all rcu head initializations, except on_stack initializationsPaul E. McKenney2010-05-125-1/+14
| | | | | | | | | Remove all rcu head inits. We don't care about the RCU head state before passing it to call_rcu() anyway. Only leave the "on_stack" variants so debugobjects can keep track of objects on stack. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu head introduce rcu head init on stackMathieu Desnoyers2010-05-111-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PEM: o Would it be possible to make this bisectable as follows? a. Insert a new patch after current patch 4/6 that defines destroy_rcu_head_on_stack(), init_rcu_head_on_stack(), and init_rcu_head() with their !CONFIG_DEBUG_OBJECTS_RCU_HEAD definitions. This patch performs this transition. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> CC: David S. Miller <davem@davemloft.net> CC: akpm@linux-foundation.org CC: mingo@elte.hu CC: laijs@cn.fujitsu.com CC: dipankar@in.ibm.com CC: josh@joshtriplett.org CC: dvhltc@us.ibm.com CC: niv@us.ibm.com CC: tglx@linutronix.de CC: peterz@infradead.org CC: rostedt@goodmis.org CC: Valdis.Kletnieks@vt.edu CC: dhowells@redhat.com CC: eric.dumazet@gmail.com CC: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* Debugobjects transition checkMathieu Desnoyers2010-05-112-3/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement a basic state machine checker in the debugobjects. This state machine checker detects races and inconsistencies within the "active" life of a debugobject. The checker only keeps track of the current state; all the state machine logic is kept at the object instance level. The checker works by adding a supplementary "unsigned int astate" field to the debug_obj structure. It keeps track of the current "active state" of the object. The only constraints that are imposed on the states by the debugobjects system is that: - activation of an object sets the current active state to 0, - deactivation of an object expects the current active state to be 0. For the rest of the states, the state mapping is determined by the specific object instance. Therefore, the logic keeping track of the state machine is within the specialized instance, without any need to know about it at the debugobject level. The current object active state is changed by calling: debug_object_active_state(addr, descr, expect, next) where "expect" is the expected state and "next" is the next state to move to if the expected state is found. A warning is generated if the expected is not found. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David S. Miller <davem@davemloft.net> CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> CC: akpm@linux-foundation.org CC: mingo@elte.hu CC: laijs@cn.fujitsu.com CC: dipankar@in.ibm.com CC: josh@joshtriplett.org CC: dvhltc@us.ibm.com CC: niv@us.ibm.com CC: peterz@infradead.org CC: rostedt@goodmis.org CC: Valdis.Kletnieks@vt.edu CC: dhowells@redhat.com CC: eric.dumazet@gmail.com CC: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: fix build bug in RCU_FAST_NO_HZ buildsPaul E. McKenney2010-05-101-2/+2
| | | | Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: RCU_FAST_NO_HZ must check RCU dyntick statePaul E. McKenney2010-05-101-2/+10
| | | | | | | | | | The current version of RCU_FAST_NO_HZ reproduces the old CLASSIC_RCU dyntick-idle bug, as it fails to detect CPUs that have interrupted or NMIed out of dyntick-idle mode. Fix this by making rcu_needs_cpu() check the state in the per-CPU rcu_dynticks variables, thus correctly detecting the dyntick-idle state from an RCU perspective. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: make SRCU usable in modulesPaul E. McKenney2010-05-101-0/+2
| | | | | | | | Add a #include for mutex.h to allow SRCU to be more easily used in kernel modules. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: improve the RCU CPU-stall warning documentationPaul E. McKenney2010-05-101-23/+71
| | | | | | | | The existing Documentation/RCU/stallwarn.txt has proven unhelpful, so rework it a bit. In particular, show how to interpret the stall-warning messages. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: reduce the number of spurious RCU_SOFTIRQ invocationsPaul E. McKenney2010-05-104-22/+29
| | | | | | | | | | | | | | | | | | | | | | | | Lai Jiangshan noted that up to 10% of the RCU_SOFTIRQ are spurious, and traced this down to the fact that the current grace-period machinery will uselessly raise RCU_SOFTIRQ when a given CPU needs to go through a quiescent state, but has not yet done so. In this situation, there might well be nothing that RCU_SOFTIRQ can do, and the overhead can be worth worrying about in the ksoftirqd case. This patch therefore avoids raising RCU_SOFTIRQ in this situation. Changes since v1 (http://lkml.org/lkml/2010/3/30/122 from Lai Jiangshan): o Omit the rcu_qs_pending() prechecks, as they aren't that much less expensive than the quiescent-state checks. o Merge with the set_need_resched() patch that reduces IPIs. o Add the new n_rp_report_qs field to the rcu_pending tracing output. o Update the tracing documentation accordingly. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: permit discontiguous cpu_possible_mask CPU numberingPaul E. McKenney2010-05-101-1/+1
| | | | | | | | | | TREE_RCU assumes that CPU numbering is contiguous, but some users need large holes in the numbering to better map to hardware layout. This patch makes TREE_RCU (and TREE_PREEMPT_RCU) tolerate large holes in the CPU numbering. However, NR_CPUS must still be greater than the largest CPU number. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: improve RCU CPU stall-warning messagesPaul E. McKenney2010-05-102-9/+12
| | | | | | | | | | | The existing RCU CPU stall-warning messages can be confusing, especially in the case where one CPU detects a single other stalled CPU. In addition, the console messages did not say which flavor of RCU detected the stall, which can make it difficult to work out exactly what is causing the stall. This commit improves these messages. Requested-by: Dhaval Giani <dhaval.giani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: print boot-time console messages if RCU configs out of ordinaryPaul E. McKenney2010-05-102-8/+42
| | | | | | | | | | | | | | Print boot-time messages if tracing is enabled, if fanout is set to non-default values, if exact fanout is specified, if accelerated dyntick-idle grace periods have been enabled, if RCU-lockdep is enabled, if rcutorture has been boot-time enabled, if the CPU stall detector has been disabled, or if four-level hierarchy has been enabled. This is all for TREE_RCU and TREE_PREEMPT_RCU. TINY_RCU will be handled separately, if at all. Suggested-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: disable CPU stall warnings upon panicPaul E. McKenney2010-05-101-0/+24
| | | | | | | | | The current RCU CPU stall warnings remain enabled even after a panic occurs, which some people have found to be a bit counterproductive. This patch therefore uses a notifier to disable stall warnings once a panic occurs. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: enable CPU_STALL_VERBOSE by defaultPaul E. McKenney2010-05-101-1/+1
| | | | | | | | | | The CPU_STALL_VERBOSE kernel configuration parameter was added to 2.6.34 to identify any preempted/blocked tasks that were preventing the current grace period from completing when running preemptible RCU. As is conventional for new configurations parameters, this defaulted disabled. It is now time to enable it by default. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: slim down rcutiny by removing rcu_scheduler_active and friendsPaul E. McKenney2010-05-107-22/+82
| | | | | | | | | TINY_RCU does not need rcu_scheduler_active unless CONFIG_DEBUG_LOCK_ALLOC. So conditionally compile rcu_scheduler_active in order to slim down rcutiny a bit more. Also gets rid of an EXPORT_SYMBOL_GPL, which is responsible for most of the slimming. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: refactor RCU's context-switch handlingPaul E. McKenney2010-05-106-11/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The addition of preemptible RCU to treercu resulted in a bit of confusion and inefficiency surrounding the handling of context switches for RCU-sched and for RCU-preempt. For RCU-sched, a context switch is a quiescent state, pure and simple, just like it always has been. For RCU-preempt, a context switch is in no way a quiescent state, but special handling is required when a task blocks in an RCU read-side critical section. However, the callout from the scheduler and the outer loop in ksoftirqd still calls something named rcu_sched_qs(), whose name is no longer accurate. Furthermore, when rcu_check_callbacks() notes an RCU-sched quiescent state, it ends up unnecessarily (though harmlessly, aside from the performance hit) enqueuing the current task if it happens to be running in an RCU-preempt read-side critical section. This not only increases the maximum latency of scheduler_tick(), it also needlessly increases the overhead of the next outermost rcu_read_unlock() invocation. This patch addresses this situation by separating the notion of RCU's context-switch handling from that of RCU-sched's quiescent states. The context-switch handling is covered by rcu_note_context_switch() in general and by rcu_preempt_note_context_switch() for preemptible RCU. This permits rcu_sched_qs() to handle quiescent states and only quiescent states. It also reduces the maximum latency of scheduler_tick(), though probably by much less than a microsecond. Finally, it means that tasks within preemptible-RCU read-side critical sections avoid incurring the overhead of queuing unless there really is a context switch. Suggested-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org>
* rcu: rename rcutiny rcu_ctrlblk to rcu_sched_ctrlblkPaul E. McKenney2010-05-101-6/+7
| | | | | | Make naming line up in preparation for CONFIG_TINY_PREEMPT_RCU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: shrink rcutiny by making synchronize_rcu_bh() be inlinePaul E. McKenney2010-05-104-10/+15
| | | | | | | | Because synchronize_rcu_bh() is identical to synchronize_sched(), make the former a static inline invoking the latter, saving the overhead of an EXPORT_SYMBOL_GPL() and the duplicate code. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: fix now-bogus rcu_scheduler_active comments.Paul E. McKenney2010-05-101-2/+4
| | | | | | | | The rcu_scheduler_active check has been wrapped into the new debug_lockdep_rcu_enabled() function, so update the comments to reflect this new reality. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: Fix bogus CONFIG_PROVE_LOCKING in comments to reflect reality.Paul E. McKenney2010-05-102-9/+10
| | | | | | It is CONFIG_DEBUG_LOCK_ALLOC rather than CONFIG_PROVE_LOCKING, so fix it. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: ignore offline CPUs in last non-dyntick-idle CPU checkLai Jiangshan2010-05-101-1/+1
| | | | | | | | | | Offline CPUs are not in nohz_cpu_mask, but can be ignored when checking for the last non-dyntick-idle CPU. This patch therefore only checks online CPUs for not being dyntick idle, allowing fast entry into full-system dyntick-idle state even when there are some offline CPUs. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: move some code from macro to functionLai Jiangshan2010-05-101-9/+9
| | | | | | | | | | | Shrink the RCU_INIT_FLAVOR() macro by moving all but the initialization of the ->rda[] array to rcu_init_one(). The call to rcu_init_one() can then be moved to the end of the RCU_INIT_FLAVOR() macro, which is required because rcu_boot_init_percpu_data(), which is now called from rcu_init_one(), depends on the initialization of the ->rda[] array. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: make dead code really deadLai Jiangshan2010-05-101-2/+2
| | | | | | | cleanup: make dead code really dead Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: substitute set_need_resched for sending resched IPIsPaul E. McKenney2010-05-101-0/+10
| | | | | | | | | | | This patch adds a check to __rcu_pending() that does a local set_need_resched() if the current CPU is holding up the current grace period and if force_quiescent_state() will be called soon. The goal is to reduce the probability that force_quiescent_state() will need to do smp_send_reschedule(), which sends an IPI and is therefore more expensive on most architectures. Signed-off-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
* rcu: optionally leave lockdep enabled after RCU lockdep splatLai Jiangshan2010-05-103-4/+26
| | | | | | | | | | | | | | | | | | | There is no need to disable lockdep after an RCU lockdep splat, so remove the debug_lockdeps_off() from lockdep_rcu_dereference(). To avoid repeated lockdep splats, use a static variable in the inlined rcu_dereference_check() and rcu_dereference_protected() macros so that a given instance splats only once, but so that multiple instances can be detected per boot. This is controlled by a new config variable CONFIG_PROVE_RCU_REPEATEDLY, which is disabled by default. This provides the normal lockdep behavior by default, but permits people who want to find multiple RCU-lockdep splats per boot to easily do so. Requested-by: Eric Paris <eparis@redhat.com> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Tested-by: Eric Paris <eparis@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* Linux 2.6.34-rc7v2.6.34-rc7Linus Torvalds2010-05-101-1/+1
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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6Linus Torvalds2010-05-107-17/+62
|\ | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: [SCSI] Retry commands with UNIT_ATTENTION sense codes to fix ext3/ext4 I/O error [SCSI] Enable retries for SYNCRONIZE_CACHE commands to fix I/O error [SCSI] scsi_debug: virtual_gb ignores sector_size [SCSI] libiscsi: regression: fix header digest errors [SCSI] fix locking around blk_abort_request() [SCSI] advansys: fix narrow board error path
| * [SCSI] Retry commands with UNIT_ATTENTION sense codes to fix ext3/ext4 I/O errorJames Bottomley2010-05-051-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's nastyness in the way we currently handle barriers (and discards): They're effectively filesystem commands, but they get processed as BLOCK_PC commands. Unfortunately BLOCK_PC commands are taken by SCSI to be SG_IO commands and the issuer expects to see and handle any returned errors, however trivial. This leads to a huge problem, because the block layer doesn't expect this to happen and any trivially retryable error on a barrier causes an immediate I/O error to the filesystem. The only real way to hack around this is to take the usual class of offending errors (unit attentions) and make them all retryable in the case of a REQ_HARDBARRIER. A correct fix would involve a rework of the entire block and SCSI submit system, and so is out of scope for a quick fix. Cc: Hannes Reinecke <hare@suse.de> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
| * [SCSI] Enable retries for SYNCRONIZE_CACHE commands to fix I/O errorHannes Reinecke2010-05-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Some arrays are giving I/O errors with ext3 filesystems when SYNCHRONIZE_CACHE gets a UNIT_ATTENTION. What is happening is that these commands have no retries, so the UNIT_ATTENTION causes the barrier to fail. We should be enable retries here to clear any transient error and allow the barrier to succeed. Signed-off-by: Hannes Reinecke <hare@suse.de> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
| * [SCSI] scsi_debug: virtual_gb ignores sector_sizeDouglas Gilbert2010-05-021-1/+2
| | | | | | | | | | | | | | | | | | | | In the scsi_debug driver, the virtual_gb option ignores the sector_size, implicitly assuming that is 512 bytes. So if 'virtual_gb=1 sector_size=4096' the result is an 8 GB (virtual) disk. Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
| * [SCSI] libiscsi: regression: fix header digest errorsMike Christie2010-05-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a regression introduced with this commit: commit d3305f3407fa3e9452079ec6cc8379067456e4aa Author: Mike Christie <michaelc@cs.wisc.edu> Date: Thu Aug 20 15:10:58 2009 -0500 [SCSI] libiscsi: don't increment cmdsn if cmd is not sent in 2.6.32. When I moved the hdr->cmdsn after init_task, I added a bug when header digests are used. The problem is that the LLD may calculate the header digest in init_task, so if we then set the cmdsn after the init_task call we change what the digest will be calculated by the target. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
| * [SCSI] fix locking around blk_abort_request()Tejun Heo2010-05-012-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | blk_abort_request() expects queue lock to be held by the caller. Grab it before calling the function. Lack of this synchronization led to infinite loop on corrupt q->timeout_list. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org Signed-off-by: James Bottomley <James.Bottomley@suse.de>
| * [SCSI] advansys: fix narrow board error pathHerton Ronaldo Krzesinski2010-05-011-14/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | Error handling on advansys_board_found is fixed, because it's buggy in the case we have an ASC_NARROW_BOARD set and failure happens on AscInitAsc1000Driver step: it was freeing items of wrong struct in the dvc_var union of struct asc_board, which could lead to an oops in the case we set some of the fields in struct of narrow board as code was choosing to always freeing wide board fields, and not everything was being freed/released properly. Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* | cpuidle: Fix incorrect optimizationArjan van de Ven2010-05-101-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 672917dcc78 ("cpuidle: menu governor: reduce latency on exit") added an optimization, where the analysis on the past idle period moved from the end of idle, to the beginning of the new idle. Unfortunately, this optimization had a bug where it zeroed one key variable for new use, that is needed for the analysis. The fix is simple, zero the variable after doing the work from the previous idle. During the audit of the code that found this issue, another issue was also found; the ->measured_us data structure member is never set, a local variable is always used instead. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Corrado Zoccolo <czoccolo@gmail.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds2010-05-072-3/+9
|\ \ | | | | | | | | | | | | | | | * 'for-linus' of git://neil.brown.name/md: md: restore ability of spare drives to spin down. md/raid6: Fix raid-6 read-error correction in degraded state
| * | md: restore ability of spare drives to spin down.NeilBrown2010-05-071-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some time ago we stopped the clean/active metadata updates from being written to a 'spare' device in most cases so that it could spin down and say spun down. Device failure/removal etc are still recorded on spares. However commit 51d5668cb2e3fd1827a55 broke this 50% of the time, depending on whether the event count is even or odd. The change log entry said: This means that the alignment between 'odd/even' and 'clean/dirty' might take a little longer to attain, how ever the code makes no attempt to create that alignment, so it could take arbitrarily long. So when we find that clean/dirty is not aligned with odd/even, force a second metadata-update immediately. There are already cases where a second metadata-update is needed immediately (e.g. when a device fails during the metadata update). We just piggy-back on that. Reported-by: Joe Bryant <tenminjoe@yahoo.com> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
| * | md/raid6: Fix raid-6 read-error correction in degraded stateGabriele A. Trombetti2010-05-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix: Raid-6 was not trying to correct a read-error when in singly-degraded state and was instead dropping one more device, going to doubly-degraded state. This patch fixes this behaviour. Tested-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com> Reported-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
* | | Merge branch 'urgent' of ↵Linus Torvalds2010-05-073-13/+11
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 * 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6: pcmcia: fix compilation after 16bit state locking changes pcmcia: order userspace suspend and resume requests pcmcia: avoid pccard_validate_cis failure in resume callpath
| * | | pcmcia: fix compilation after 16bit state locking changesMarc Zyngier2010-05-041-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 04de0816 (pcmcia: pcmcia_dev_present bugfix) broke the deprecated ioctl layer. Fix it by getting rid of references to unexisting fields. Signed-off-by: Marc Zyngier <maz@misterjones.org> Reported-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
| * | | pcmcia: order userspace suspend and resume requestsDominik Brodowski2010-05-041-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Assert that userspace suspend and resume requests appearing (almost) immediately are executed in the following order: suspend, resume. This should result in "pccardctl reset" behaving the same as before. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
| * | | pcmcia: avoid pccard_validate_cis failure in resume callpathDominik Brodowski2010-05-031-0/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | If the PCMCIA CIS changed before a resume event (e.g. due to a card exchange while being suspended, possibly also during a call to "pccardctl reset"), also set the function count to zero so that the subsequent call to pccard_validate_cis() does not fail. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* | | Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds2010-05-073-5/+7
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://git.kernel.dk/linux-2.6-block: blk-cgroup: Fix an RCU warning in blkiocg_create() blk-cgroup: Fix RCU correctness warning in cfq_init_queue() drbd: don't expose failed local READ to upper layers
| * | | blk-cgroup: Fix an RCU warning in blkiocg_create()Li Zefan2010-05-071-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | with CONFIG_PROVE_RCU=y, a warning can be triggered: # mount -t cgroup -o blkio xxx /mnt # mkdir /mnt/subgroup ... kernel/cgroup.c:4442 invoked rcu_dereference_check() without protection! ... To fix this, we avoid caling css_depth() here, which is a bit simpler than the original code. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | blk-cgroup: Fix RCU correctness warning in cfq_init_queue()Vivek Goyal2010-05-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is necessary to be in an RCU read-side critical section when invoking css_id(), so this patch adds one to blkiocg_add_blkio_group(). This is actually a false positive, because this is called at initialization time and hence always refers to the root cgroup, which cannot go away. [ 103.790505] =================================================== [ 103.790509] [ INFO: suspicious rcu_dereference_check() usage. ] [ 103.790511] --------------------------------------------------- [ 103.790514] kernel/cgroup.c:4432 invoked rcu_dereference_check() without protection! [ 103.790517] [ 103.790517] other info that might help us debug this: [ 103.790519] [ 103.790521] [ 103.790521] rcu_scheduler_active = 1, debug_locks = 1 [ 103.790524] 4 locks held by bash/4422: [ 103.790526] #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff8114befa>] sysfs_write_file+0x3c/0x144 [ 103.790537] #1: (s_active#102){.+.+.+}, at: [<ffffffff8114bfa5>] sysfs_write_file+0xe7/0x144 [ 103.790544] #2: (&q->sysfs_lock){+.+.+.}, at: [<ffffffff812263b1>] queue_attr_store+0x49/0x8f [ 103.790552] #3: (&(&blkcg->lock)->rlock){......}, at: [<ffffffff8122e4db>] blkiocg_add_blkio_group+0x2b/0xad [ 103.790560] [ 103.790561] stack backtrace: [ 103.790564] Pid: 4422, comm: bash Not tainted 2.6.34-rc4-blkio-second-crash #81 [ 103.790567] Call Trace: [ 103.790572] [<ffffffff81068f57>] lockdep_rcu_dereference+0x9d/0xa5 [ 103.790577] [<ffffffff8107fac1>] css_id+0x44/0x57 [ 103.790581] [<ffffffff8122e503>] blkiocg_add_blkio_group+0x53/0xad [ 103.790586] [<ffffffff81231936>] cfq_init_queue+0x139/0x32c [ 103.790591] [<ffffffff8121f2d0>] elv_iosched_store+0xbf/0x1bf [ 103.790595] [<ffffffff812263d8>] queue_attr_store+0x70/0x8f [ 103.790599] [<ffffffff8114bfa5>] ? sysfs_write_file+0xe7/0x144 [ 103.790603] [<ffffffff8114bfc6>] sysfs_write_file+0x108/0x144 [ 103.790609] [<ffffffff810f527f>] vfs_write+0xae/0x10b [ 103.790612] [<ffffffff81069863>] ? trace_hardirqs_on_caller+0x10c/0x130 [ 103.790616] [<ffffffff810f539c>] sys_write+0x4a/0x6e [ 103.790622] [<ffffffff81002b5b>] system_call_fastpath+0x16/0x1b [ 103.790625] Located-by: Miles Lane <miles.lane@gmail.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | Merge branch 'for-jens' of git://git.drbd.org/linux-2.6-drbd into for-linusJens Axboe2010-05-041-1/+1
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| | * | drbd: don't expose failed local READ to upper layersLars Ellenberg2010-05-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fix regression introduced in 8.3.3: commit a9b17323f2875f5d9b132c2b476a750bf44b10c7 Author: Lars Ellenberg <lars.ellenberg@linbit.com> Date: Wed Aug 12 15:18:33 2009 +0200 out-of-spinlock completion of master bio : (bio_rw(bio) == READA) ? read_completed_with_error : read_ahead_completed_with_error; is obviously not what was intended. No one noticed because of * page-cache at work, * local RAIDs Impact: Failed local READs are not retried remotely, but errored to upper layers, causing filesystems to remount read-only, or worse. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
* | | | Merge branch 'drm-linus' of ↵Linus Torvalds2010-05-074-61/+4
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 * 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: drm/ttm: Remove the ttm_bo_block_reservation() function. drm/ttm: Remove some leftover debug messages. drm/radeon: async event synchronization for drmWaitVblank
| * | | | drm/ttm: Remove the ttm_bo_block_reservation() function.Thomas Hellstrom2010-05-072-57/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's unused and buggy in its current form, since it can place a bo in the reserved state without removing it from lru lists. Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
| * | | | drm/ttm: Remove some leftover debug messages.Thomas Hellstrom2010-05-071-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
| * | | | drm/radeon: async event synchronization for drmWaitVblankJerome Glisse2010-05-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bring radeon up to speed with the async event synchronization for drmWaitVblank. See c9a9c5e02aedc1a2815877b0268f886d2640b771 for more information. Without this patch event never get delivered to userspace client. Signed-off-by: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
* | | | | virtio: initialize earlierStijn Tintel2010-05-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move initialization of the virtio framework before the initialization of mtd, so that block2mtd can be used on virtio-based block devices. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=15644 Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>