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2019-01-25doc: Fix outdated linksJunchang Wang
Fix outdated links in whatisRCU.txt. Signed-off-by: Junchang Wang <junchangwang@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25doc: CPU-hotplug notifiers cannot invoke synchronize_srcu() or srcu_barrier()Paul E. McKenney
SRCU's synchronize_srcu() may not be invoked from CPU-hotplug notifiers, due to the fact that SRCU grace periods make use of timers and the possibility of timers being temporarily stranded on the outgoing CPU. This stranding of timers means that timers posted to the outgoing CPU will not fire until late in the CPU-hotplug process. The problem is that if a notifier is waiting on an SRCU grace period, that grace period is waiting on a timer, and that timer is stranded on the outgoing CPU, then the notifier will never be awakened, in other words, deadlock has occurred. This same situation of course also prohibits srcu_barrier() from being invoked from CPU-hotplug notifiers. This commit therefore updates the requirements to include this restriction. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25doc: Now jiffies_till_sched_qs solicits help from cond_resched()Paul E. McKenney
The rcutree.jiffies_till_sched_qs kernel boot parameter used to solicit help only from rcu_note_context_switch(), but now also solicits help from cond_resched(). This commit therefore updates kernel-parameters.txt accordingly. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25Merge branches 'consolidate.2019.01.26a' and 'fwd.2019.01.26a' into HEADPaul E. McKenney
consolidate.2019.01.26a: RCU flavor consolidation cleanups. fwd.2019.01.26a: RCU grace-period forward-progress fixes.
2019-01-25rcu: Prevent needless ->gp_seq_needed update in __note_gp_changes()Zhang, Jun
Currently, __note_gp_changes() checks to see if the rcu_node structure's ->gp_seq_needed is greater than or equal to that of the rcu_data structure, and if so, updates the rcu_data structure's ->gp_seq_needed field. This results in a useless store in the case where the two fields are equal. This commit therefore carries out this store only in the case where the rcu_node structure's ->gp_seq_needed is strictly greater than that of the rcu_data structure. Signed-off-by: "Zhang, Jun" <jun.zhang@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Link: https://lkml.kernel.org/r/88DC34334CA3444C85D647DBFA962C2735AD5F77@SHSMSX104.ccr.corp.intel.com
2019-01-25rcu: Do RCU GP kthread self-wakeup from softirq and interruptZhang, Jun
The rcu_gp_kthread_wake() function is invoked when it might be necessary to wake the RCU grace-period kthread. Because self-wakeups are normally a useless waste of CPU cycles, if rcu_gp_kthread_wake() is invoked from this kthread, it naturally refuses to do the wakeup. Unfortunately, natural though it might be, this heuristic fails when rcu_gp_kthread_wake() is invoked from an interrupt or softirq handler that interrupted the grace-period kthread just after the final check of the wait-event condition but just before the schedule() call. In this case, a wakeup is required, even though the call to rcu_gp_kthread_wake() is within the RCU grace-period kthread's context. Failing to provide this wakeup can result in grace periods failing to start, which in turn results in out-of-memory conditions. This race window is quite narrow, but it actually did happen during real testing. It would of course need to be fixed even if it was strictly theoretical in nature. This patch does not Cc stable because it does not apply cleanly to earlier kernel versions. Fixes: 48a7639ce80c ("rcu: Make callers awaken grace-period kthread") Reported-by: "He, Bo" <bo.he@intel.com> Co-developed-by: "Zhang, Jun" <jun.zhang@intel.com> Co-developed-by: "He, Bo" <bo.he@intel.com> Co-developed-by: "xiao, jin" <jin.xiao@intel.com> Co-developed-by: Bai, Jie A <jie.a.bai@intel.com> Signed-off: "Zhang, Jun" <jun.zhang@intel.com> Signed-off: "He, Bo" <bo.he@intel.com> Signed-off: "xiao, jin" <jin.xiao@intel.com> Signed-off: Bai, Jie A <jie.a.bai@intel.com> Signed-off-by: "Zhang, Jun" <jun.zhang@intel.com> [ paulmck: Switch from !in_softirq() to "!in_interrupt() && !in_serving_softirq() to avoid redundant wakeups and to also handle the interrupt-handler scenario as well as the softirq-handler scenario that actually occurred in testing. ] Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Link: https://lkml.kernel.org/r/CD6925E8781EFD4D8E11882D20FC406D52A11F61@SHSMSX104.ccr.corp.intel.com
2019-01-25rcu: Add sysrq rcu_node-dump capabilityPaul E. McKenney
Life is hard if RCU manages to get stuck without triggering RCU CPU stall warnings or triggering the rcu_check_gp_start_stall() checks for failing to start a grace period. This commit therefore adds a boot-time-selectable sysrq key (commandeering "y") that allows manually dumping Tree RCU state. The new rcutree.sysrq_rcu kernel boot parameter must be set for this sysrq to be available. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Protect rcu_check_gp_kthread_starvation() access to ->gp_flagsPaul E. McKenney
The rcu_check_gp_kthread_starvation() function can be invoked without holding locks, so the access to the rcu_state structure's ->gp_flags field must be protected with READ_ONCE(). This commit therefore adds this protection. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Improve diagnostics for failed RCU grace-period startPaul E. McKenney
If a grace period fails to start (for example, because you commented out the last two lines of rcu_accelerate_cbs_unlocked()), rcu_core() will invoke rcu_check_gp_start_stall(), which will notice and complain. However, this complaint is lacking crucial debugging information such as when the last wakeup executed and what the value of ->gp_seq was at that time. This commit therefore removes the current pr_alert() from rcu_check_gp_start_stall(), instead invoking show_rcu_gp_kthreads(), which has been updated to print the needed information, which is collected by rcu_gp_kthread_wake(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Update NOCB commentsPaul E. McKenney
This commit updates a few obsolete comments in the RCU callback-offload code. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Remove unused rcu_cpu_kthread_cpu per-CPU variablePaul E. McKenney
The rcu_cpu_kthread_cpu used to provide debugfs information, but is no longer used. This commit therefore removes it. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Move rcu_cpu_has_work to rcu_data structurePaul E. McKenney
Given that RCU has a perfectly good per-CPU rcu_data structure, most per-CPU quantities should be stored there. This commit therefore moves the rcu_cpu_has_work per-CPU variable to the rcu_data structure. This also makes this variable unconditionally present, which should be acceptable given the memory reduction due to the RCU flavor consolidation and also due to simplifications this will enable. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Remove unused rcu_cpu_kthread_loops per-CPU variablePaul E. McKenney
The rcu_cpu_kthread_loops variable used to provide debugfs information, but is no longer used. This commit therefore removes it. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Move rcu_cpu_kthread_status to rcu_data structurePaul E. McKenney
Given that RCU has a perfectly good per-CPU rcu_data structure, most per-CPU quantities should be stored there. This commit therefore moves the rcu_cpu_kthread_status per-CPU variable to the rcu_data structure. This also makes this variable unconditionally present, which should be acceptable given the memory reduction due to the RCU flavor consolidation and also due to simplifications this will enable. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Move rcu_cpu_kthread_task to rcu_data structurePaul E. McKenney
Given that RCU has a perfectly good per-CPU rcu_data structure, most per-CPU quantities should be stored there. This commit therefore moves the rcu_cpu_kthread_task per-CPU variable to the rcu_data structure. This also makes this variable unconditionally present, which should be acceptable given the memory reduction due to the RCU flavor consolidation and also due to simplifications this will enable. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Accommodate zero jiffies_till_first_fqs and kthread kickingPaul E. McKenney
It is perfectly fine to set the rcutree.jiffies_till_first_fqs boot parameter to zero, in fact, this can be useful on specialty systems that usually have at least one idle CPU and that need fast grace periods. This is because this setting causes the RCU grace-period kthread to scan for idle threads immediately after grace-period initialization, as opposed to waiting several jiffies to do so. It is also perfectly fine to set the rcutree.rcu_kick_kthreads kernel parameter, which gives the RCU grace-period kthread an extra wakeup if it doesn't make progress for a period of three times the setting of the rcutree.jiffies_till_first_fqs boot parameter. This is of course problematic when the value of this parameter is zero, as it can result in unnecessary wakeup IPIs along with unnecessary WARN_ONCE() invocations. This commit therefore defers kthread kicking for at least two jiffies, regardless of the setting of rcutree.jiffies_till_first_fqs. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Remove wrapper definitions for obsolete RCU update functionsPaul E. McKenney
None of synchronize_rcu_bh, synchronize_rcu_bh_expedited, call_rcu_bh, rcu_barrier_bh, synchronize_sched, synchronize_sched_expedited, call_rcu_sched, rcu_barrier_sched, get_state_synchronize_sched, and cond_synchronize_sched are actually used. This commit therefore removes their trivial wrapper-function definitions. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Discard separate per-CPU callback countsPaul E. McKenney
Back when there were multiple flavors of RCU, it was necessary to separately count lazy and non-lazy callbacks for each CPU. These counts were used in CONFIG_RCU_FAST_NO_HZ kernels to determine how long a newly idle CPU should be allowed to sleep before handling its RCU callbacks. But now that there is only one flavor, the callback counts for a given CPU's sole rcu_data structure are the counts for that CPU. This commit therefore removes the rcu_data structure's ->nonlazy_posted and ->nonlazy_posted_snap fields, the rcu_idle_count_callbacks_posted() and rcu_cpu_has_callbacks() functions, repurposes the rcu_data structure's ->all_lazy field to record the laziness state at the beginning of the latest idle sojourn, and modifies CONFIG_RCU_FAST_NO_HZ RCU CPU stall warnings accordingly. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Inline _synchronize_rcu_expedited() into synchronize_rcu_expedited()Paul E. McKenney
Now that _synchronize_rcu_expedited() has only one caller, and given that this is a tail call, this commit inlines _synchronize_rcu_expedited() into synchronize_rcu_expedited(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Consolidate PREEMPT and !PREEMPT synchronize_rcu()Paul E. McKenney
Now that rcu_blocking_is_gp() makes the correct immediate-return decision for both PREEMPT and !PREEMPT, a single implementation of synchronize_rcu() will work correctly under both configurations. This commit therefore eliminates a few lines of code by consolidating the two implementations of synchronize_rcu(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Consolidate PREEMPT and !PREEMPT synchronize_rcu_expedited()Paul E. McKenney
The CONFIG_PREEMPT=n and CONFIG_PREEMPT=y implementations of synchronize_rcu_expedited() are quite similar, and with small modifications to rcu_blocking_is_gp() can be made identical. This commit therefore makes this change in order to save a few lines of code and to reduce the amount of duplicate code. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Determine expedited-GP IPI handler at build timePaul E. McKenney
Back when there could be multiple RCU flavors running in the same kernel at the same time, it was necessary to specify the expedited grace-period IPI handler at runtime. Now that there is only one RCU flavor, the IPI handler can be determined at build time. There is therefore no longer any reason for the RCU-preempt and RCU-sched IPI handlers to have different names, nor is there any reason to pass these handlers in function arguments and in the data structures enclosing workqueues. This commit therefore makes all these changes, pushing the specification of the expedited grace-period IPI handler down to the point of use. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Inline rcu_kthread_do_work() into its sole remaining callerPaul E. McKenney
The rcu_kthread_do_work() function has a single-line body and only one remaining caller. This commit therefore saves a few lines of code by inlining rcu_kthread_do_work() into its sole remaining caller. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Eliminate RCU_BH_FLAVOR and RCU_SCHED_FLAVORPaul E. McKenney
Now that the RCU flavors have been consolidated, RCU_BH_FLAVOR and RCU_SCHED_FLAVOR are no longer used. This commit therefore saves a few lines by removing them. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Inline force_quiescent_state() into rcu_force_quiescent_state()Paul E. McKenney
Given that rcu_force_quiescent_state() is a simple wrapper around force_quiescent_state(), this commit saves a few lines of code by inlining force_quiescent_state() into rcu_force_quiescent_state(), and changing all references to force_quiescent_state() to instead invoke rcu_force_quiescent_state(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Make expedited IPI handler return after handling critical sectionPaul E. McKenney
During expedited RCU grace-period initialization, IPIs are sent to all non-idle online CPUs. The IPI handler checks to see if the CPU is in quiescent state, reporting one if so. This handler looks at three different cases: (1) The CPU is not in an rcu_read_lock()-based critical section, (2) The CPU is in the process of exiting an rcu_read_lock()-based critical section, and (3) The CPU is in an rcu_read_lock()-based critical section. In case (2), execution falls through into case (3). This is harmless from a functionality viewpoint, but can result in needless overhead during an improbable corner case. This commit therefore adds the "return" statement needed to prevent fall-through. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25rcu: Rename and comment changes due to only one rcuo kthread per CPUPaul E. McKenney
Given RCU flavor consolidation, the name rcu_spawn_all_nocb_kthreads() is quite misleading. It no longer ever creates more than one kthread, and it does so only for the specified CPU. This commit therefore changes this name to the more descriptive rcu_spawn_cpu_nocb_kthread(), and also fixes up a similar issue in its header comment while in the area. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25sched: Replace synchronize_sched() with synchronize_rcu()Paul E. McKenney
Now that synchronize_rcu() waits for preempt-disable regions of code as well as RCU read-side critical sections, synchronize_sched() can be replaced by synchronize_rcu(), in fact, synchronize_sched() is now completely equivalent to synchronize_rcu(). This commit therefore replaces synchronize_sched() with synchronize_rcu() so that synchronize_sched() can eventually be removed entirely. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
2019-01-25sched: Replace call_rcu_sched() with call_rcu()Paul E. McKenney
Now that call_rcu()'s callback is not invoked until after all preempt-disable regions of code have completed (in addition to explicitly marked RCU read-side critical sections), call_rcu() can be used in place of call_rcu_sched(). This commit therefore makes that change. While in the area, this commit also updates an outdated header comment for for_each_domain(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
2019-01-21tools/memory-model: Make scripts take "-j" abbreviation for "--jobs"Paul E. McKenney
The "--jobs" argument to the litmus-test scripts is similar to the "-jN" argument to "make", so this commit allows the "-jN" form as well. While in the area, it also prohibits the various forms of "-j0". Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akiyks@gmail.com Cc: boqun.feng@gmail.com Cc: dhowells@redhat.com Cc: j.alglave@ucl.ac.uk Cc: linux-arch@vger.kernel.org Cc: luc.maranget@inria.fr Cc: npiggin@gmail.com Cc: parri.andrea@gmail.com Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/20181203230451.28921-3-paulmck@linux.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21tools/memory-model: Add scripts to check github litmus testsPaul E. McKenney
The https://github.com/paulmckrcu/litmus repository contains a large number of C-language litmus tests that include "Result:" comments predicting the verification result. This commit adds a number of scripts that run tests on these litmus tests: checkghlitmus.sh: Runs all litmus tests in the https://github.com/paulmckrcu/litmus archive that are C-language and that have "Result:" comment lines documenting expected results, comparing the actual results to those expected. Clones the repository if it has not already been cloned into the "tools/memory-model/litmus" directory. initlitmushist.sh Run all litmus tests having no more than the specified number of processes given a specified timeout, recording the results in .litmus.out files. Clones the repository if it has not already been cloned into the "tools/memory-model/litmus" directory. newlitmushist.sh For all new or updated litmus tests having no more than the specified number of processes given a specified timeout, run and record the results in .litmus.out files. checklitmushist.sh Run all litmus tests having .litmus.out files from previous initlitmushist.sh or newlitmushist.sh runs, comparing the herd output to that of the original runs. The above scripts will run litmus tests concurrently, by default with one job per available CPU. Giving any of these scripts the --help argument will cause them to print usage information. This commit also adds a number of helper scripts that are not intended to be invoked from the command line: cmplitmushist.sh: Compare the output of two different runs of the same litmus test. judgelitmus.sh: Compare the output of a litmus test to its "Result:" comment line. parseargs.sh: Parse command-line arguments. runlitmushist.sh: Run the litmus tests whose pathnames are provided one per line on standard input. While in the area, this commit also makes the existing checklitmus.sh and checkalllitmus.sh scripts use parseargs.sh in order to provide a bit of uniformity. In addition, per-litmus-test status output is directed to stdout, while end-of-test summary information is directed to stderr. Finally, the error flag standardizes on "!!!" to assist those familiar with rcutorture output. The defaults for the parseargs.sh arguments may be overridden by using environment variables: LKMM_DESTDIR for --destdir, LKMM_HERD_OPTIONS for --herdoptions, LKMM_JOBS for --jobs, LKMM_PROCS for --procs, and LKMM_TIMEOUT for --timeout. [ paulmck: History-check summary-line changes per Alan Stern feedback. ] Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akiyks@gmail.com Cc: boqun.feng@gmail.com Cc: dhowells@redhat.com Cc: j.alglave@ucl.ac.uk Cc: linux-arch@vger.kernel.org Cc: luc.maranget@inria.fr Cc: npiggin@gmail.com Cc: parri.andrea@gmail.com Cc: stern@rowland.harvard.edu Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/20181203230451.28921-2-paulmck@linux.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21tools/memory-model: Model smp_mb__after_unlock_lock()Andrea Parri
The kernel documents smp_mb__after_unlock_lock() the following way: "Place this after a lock-acquisition primitive to guarantee that an UNLOCK+LOCK pair acts as a full barrier. This guarantee applies if the UNLOCK and LOCK are executed by the same CPU or if the UNLOCK and LOCK operate on the same lock variable." Formalize in LKMM the above guarantee by defining (new) mb-links according to the law: ([M] ; po ; [UL] ; (co | po) ; [LKW] ; fencerel(After-unlock-lock) ; [M]) where the component ([UL] ; co ; [LKW]) identifies "UNLOCK+LOCK pairs on the same lock variable" and the component ([UL] ; po ; [LKW]) identifies "UNLOCK+LOCK pairs executed by the same CPU". In particular, the LKMM forbids the following two behaviors (the second litmus test below is based on: Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html c.f., Section "Tree RCU Grace Period Memory Ordering Building Blocks"): C after-unlock-lock-same-cpu (* * Result: Never *) {} P0(spinlock_t *s, spinlock_t *t, int *x, int *y) { int r0; spin_lock(s); WRITE_ONCE(*x, 1); spin_unlock(s); spin_lock(t); smp_mb__after_unlock_lock(); r0 = READ_ONCE(*y); spin_unlock(t); } P1(int *x, int *y) { int r0; WRITE_ONCE(*y, 1); smp_mb(); r0 = READ_ONCE(*x); } exists (0:r0=0 /\ 1:r0=0) C after-unlock-lock-same-lock-variable (* * Result: Never *) {} P0(spinlock_t *s, int *x, int *y) { int r0; spin_lock(s); WRITE_ONCE(*x, 1); r0 = READ_ONCE(*y); spin_unlock(s); } P1(spinlock_t *s, int *y, int *z) { int r0; spin_lock(s); smp_mb__after_unlock_lock(); WRITE_ONCE(*y, 1); r0 = READ_ONCE(*z); spin_unlock(s); } P2(int *z, int *x) { int r0; WRITE_ONCE(*z, 1); smp_mb(); r0 = READ_ONCE(*x); } exists (0:r0=0 /\ 1:r0=0 /\ 2:r0=0) Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Akira Yokosawa <akiyks@gmail.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Daniel Lustig <dlustig@nvidia.com> Cc: David Howells <dhowells@redhat.com> Cc: Jade Alglave <j.alglave@ucl.ac.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luc Maranget <luc.maranget@inria.fr> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Cc: parri.andrea@gmail.com Link: http://lkml.kernel.org/r/20181203230451.28921-1-paulmck@linux.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-18Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma fixes frfom Jason Gunthorpe: "Not much so far. We have the usual batch of bugs and two fixes to code merged this cycle: - Restore valgrind support for the ioctl verbs interface merged this window, and fix a missed error code on an error path from that conversion - A user reported crash on obsolete mthca hardware - pvrdma was using the wrong command opcode toward the hypervisor - NULL pointer crash regression when dumping rdma-cm over netlink - Be conservative about exposing the global rkey" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: RDMA/uverbs: Mark ioctl responses with UVERBS_ATTR_F_VALID_OUTPUT RDMA/mthca: Clear QP objects during their allocation RDMA/vmw_pvrdma: Return the correct opcode when creating WR RDMA/cma: Add cm_id restrack resource based on kernel or user cm_id type RDMA/nldev: Don't expose unsafe global rkey to regular user RDMA/uverbs: Fix post send success return value in case of error
2019-01-18Merge tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drmLinus Torvalds
Pull drm fixes from Dave Airlie: "The rc3 fixes are a bit scattered: - meson, sun4i and rockchip all had missing of_node_put. - qxl and virtio both were advertising dma-buf to userspace when they really shouldn't have. Otherwise: meson: - modesetting regression fix i915 GVT: - one cmd parser failure fix - region cleanup fix in vGPU destroy amdgpu: - KFD fixes for arm64 mixed APU/DGPU - vega12 powerplay fix - raven DC fixes - freesync fix" * tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drm: drm/amd/display: Detach backlight from stream drm/sun4i: backend: add missing of_node_puts Revert "drm/amdgpu: validate user pitch alignment" Revert "drm/amdgpu: validate user GEM object size" drm/meson: Fix atomic mode switching regression drm/i915/gvt: Fix mmap range check drm/i915/gvt: free VFIO region space in vgpu detach drm/amd/display: Fix disabled cursor on top screen edge drm/amd/display: fix warning on raven hotplug drm/amd/display: fix PME notification not working in RV desktop drm/amd/display: Only get the connector state for VRR when toggled drm/amd/display: Pack DMCU iRAM alignment drm/amd/powerplay: run acg btc for Vega12 drm/amdkfd: Don't assign dGPUs to APU topology devices drm/amdkfd: Allow building KFD on ARM64 (v2) drm/meson: add missing of_node_put drm/virtio: drop prime import/export callbacks drm/qxl: drop prime import/export callbacks drm/i915/gvt: Allow F_CMD_ACCESS on mmio 0x21f0 drm/rockchip: add missing of_node_put
2019-01-18Merge tag 'led-fix-for-5.0-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds Pull LED fix from Jacek Anaszewski. * tag 'led-fix-for-5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: leds: lp5523: fix a missing check of return value of lp55xx_read
2019-01-18Merge tag 'hwmon-for-v5.0-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging Pull hwmon fixes from Guenter Roeck: "Minor fixes/regressions" * tag 'hwmon-for-v5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute in OF device ID table hwmon: (occ) Fix potential integer overflow hwmon: (lm80) Fix missing unlock on error in set_fan_div() hwmon: (nct6775) Enable IO mapping for NCT6797D and NCT6798D hwmon: (nct6775) Fix chip ID for NCT6798D
2019-01-18Merge tag 'drm-misc-fixes-2019-01-17' of ↵Dave Airlie
git://anongit.freedesktop.org/drm/drm-misc into drm-fixes drm-misc-fixes for v5.0-rc3: - Add missing calls to of_node_put to sun4i, meson, and rockchip. - Drop unimplemented prime callbacks in virtio and qxl, so support for prime is not advertised on those drivers. - Fix mode switching regression in meson. Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/9af07312-f435-2fda-65a2-9fe92cdf5da4@linux.intel.com
2019-01-18Merge tag 'drm-intel-fixes-2019-01-17' of ↵Dave Airlie
git://anongit.freedesktop.org/drm/drm-intel into drm-fixes drm/i915/gvt fixes for v5.0-rc3 "This contains one cmd parser failure fix to allow cmd access for one register, and fix region cleanup properly in vGPU destroy, and another fix for critical mmap size check mistake." Signed-off-by: Dave Airlie <airlied@redhat.com> From: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/87ef9bfusc.fsf@intel.com
2019-01-18Merge branch 'drm-fixes-5.0' of git://people.freedesktop.org/~agd5f/linux ↵Dave Airlie
into drm-fixes Fixes for 5.0: - Fix KFD on ARM64 - Fix KFD topology with mixed APU and dGPU systems - Powerplay fix for vega12 - DC Raven fixes - Freesync fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Alex Deucher <alexdeucher@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190116224524.3314-1-alexander.deucher@amd.com
2019-01-17leds: lp5523: fix a missing check of return value of lp55xx_readKangjie Lu
When lp55xx_read() fails, "status" is an uninitialized variable and thus may contain random value; using it leads to undefined behaviors. The fix inserts a check for the return value of lp55xx_read: if it fails, returns with its error code. Signed-off-by: Kangjie Lu <kjlu@umn.edu> Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-01-17hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute ↵Cheng-Min Ao
in OF device ID table Correct a typo in OF device ID table The last one should be 'ti,tmp442' Signed-off-by: Cheng-Min Ao <tony_ao@wiwynn.com> Signed-off-by: Yu-Hsiang Chen <matt_chen@wiwynn.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-01-18Merge tag 'afs-fixes-20190117' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull AFS fixes from David Howells: "Here's a set of fixes for AFS: - Use struct_size() for kzalloc() size calculation. - When calling YFS.CreateFile rather than AFS.CreateFile, it is possible to create a file with a file lock already held. The default value indicating no lock required is actually -1, not 0. - Fix an oops in inode/vnode validation if the target inode doesn't have a server interest assigned (ie. a server that will notify us of changes by third parties). - Fix refcounting of keys in file locking. - Fix a race in refcounting asynchronous operations in the event of an error during request transmission. The provision of a dedicated function to get an extra ref on a call is split into a separate commit" * tag 'afs-fixes-20190117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Fix race in async call refcounting afs: Provide a function to get a ref on a call afs: Fix key refcounting in file locking code afs: Don't set vnode->cb_s_break in afs_validate() afs: Set correct lock type for the yfs CreateFile afs: Use struct_size() in kzalloc()
2019-01-18Merge branch 'stable/for-linus-5.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb fix from Konrad Rzeszutek Wilk: "A tiny fix for v5.0-rc2: This fixes an issue with GPU cards not working anymore with the DMA mapping work Christopher did - as the SWIOTLB is initialized first and then free'd (as IOMMU is available) but we forgot to clear our start and end entries which are used and BOOM" * 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb: clear io_tlb_start and io_tlb_end in swiotlb_exit
2019-01-18Merge tag 'kbuild-fixes-v5.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - clean generated files in scripts/kconfig/ by 'make mrproper' - fix conflict between dead code elimination and ftrace for GCC <= 4.7 - fix external module build with CONFIG_STACKPROTECTOR - remove unused code * tag 'kbuild-fixes-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: mark prepare0 as PHONY to fix external module build openrisc: remove unneeded code in arch/openrisc/Makefile nds32: remove unneeded code in arch/nds32/Makefile ia64: remove redundant 'export AWK' kbuild: remove unused archmrproper kbuild: remove unused baseprereq kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 kconfig: clean generated *conf-cfg files
2019-01-18Merge tag 'devicetree-fixes-for-5.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull Devicetree fixes from Rob Herring: - Remove now unused struct device_node.type pointer - Fix meson-axg reset header SPDX tag - Add missing of_node_put in of_graph_get_remote_port_parent - Fix several binding doc file references and typos * tag 'devicetree-fixes-for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: dt-bindings: reset: meson-axg: fix SPDX license id dt-bindings: soc: qcom: Fix trivial language typos doc: gpio-mvebu: fix broken reference to cp110-system-controller0.txt file OF: properties: add missing of_node_put doc: bindings: fix bad reference to ARM CPU bindings dt-bindings: marvell,mmp2: fix typos in bindings doc of: Remove struct device_node.type pointer
2019-01-17afs: Fix race in async call refcountingDavid Howells
There's a race between afs_make_call() and afs_wake_up_async_call() in the case that an error is returned from rxrpc_kernel_send_data() after it has queued the final packet. afs_make_call() will try and clean up the mess, but the call state may have been moved on thereby causing afs_process_async_call() to also try and to delete the call. Fix this by: (1) Getting an extra ref for an asynchronous call for the call itself to hold. This makes sure the call doesn't evaporate on us accidentally and will allow the call to be retained by the caller in a future patch. The ref is released on leaving afs_make_call() or afs_wait_for_call_to_complete(). (2) In the event of an error from rxrpc_kernel_send_data(): (a) Don't set the call state to AFS_CALL_COMPLETE until *after* the call has been aborted and ended. This prevents afs_deliver_to_call() from doing anything with any notifications it gets. (b) Explicitly end the call immediately to prevent further callbacks. (c) Cancel any queued async_work and wait for the work if it's executing. This allows us to be sure the race won't recur when we change the state. We put the work queue's ref on the call if we managed to cancel it. (d) Put the call's ref that we got in (1). This belongs to us as long as the call is in state AFS_CALL_CL_REQUESTING. Fixes: 341f741f04be ("afs: Refcount the afs_call struct") Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17afs: Provide a function to get a ref on a callDavid Howells
Provide a function to get a reference on an afs_call struct. Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17afs: Fix key refcounting in file locking codeDavid Howells
Fix the refcounting of the authentication keys in the file locking code. The vnode->lock_key member points to a key on which it expects to be holding a ref, but it isn't always given an extra ref, however. Fixes: 0fafdc9f888b ("afs: Fix file locking") Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17afs: Don't set vnode->cb_s_break in afs_validate()Marc Dionne
A cb_interest record is not necessarily attached to the vnode on entry to afs_validate(), which can cause an oops when we try to bring the vnode's cb_s_break up to date in the default case (ie. no current callback promise and the vnode has not been deleted). Fix this by simply removing the line, as vnode->cb_s_break will be set when needed by afs_register_server_cb_interest() when we next get a callback promise from RPC call. The oops looks something like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 ... RIP: 0010:afs_validate+0x66/0x250 [kafs] ... Call Trace: afs_d_revalidate+0x8d/0x340 [kafs] ? __d_lookup+0x61/0x150 lookup_dcache+0x44/0x70 ? lookup_dcache+0x44/0x70 __lookup_hash+0x24/0xa0 do_unlinkat+0x11d/0x2c0 __x64_sys_unlink+0x23/0x30 do_syscall_64+0x4d/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: ae3b7361dc0e ("afs: Fix validation/callback interaction") Signed-off-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17kbuild: mark prepare0 as PHONY to fix external module buildMasahiro Yamada
Commit c3ff2a5193fa ("powerpc/32: add stack protector support") caused kernel panic on PowerPC when an external module is used with CONFIG_STACKPROTECTOR because the 'prepare' target was not executed for the external module build. Commit e07db28eea38 ("kbuild: fix single target build for external module") turned it into a build error because the 'prepare' target is now executed but the 'prepare0' target is missing for the external module build. External module on arm/arm64 with CONFIG_STACKPROTECTOR_PER_TASK is also broken in the same way. Move 'PHONY += prepare0' to the common place. GNU Make is fine with missing rule for phony targets. I also removed the comment which is wrong irrespective of this commit. I minimize the change so it can be easily backported to 4.20.x To fix v4.20, please backport e07db28eea38 ("kbuild: fix single target build for external module"), and then this commit. Link: https://bugzilla.kernel.org/show_bug.cgi?id=201891 Fixes: e07db28eea38 ("kbuild: fix single target build for external module") Fixes: c3ff2a5193fa ("powerpc/32: add stack protector support") Fixes: 189af4657186 ("ARM: smp: add support for per-task stack canaries") Fixes: 0a1213fa7432 ("arm64: enable per-task stack canaries") Cc: linux-stable <stable@vger.kernel.org> # v4.20 Reported-by: Samuel Holland <samuel@sholland.org> Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>