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2017-01-30perf/core: Don't re-schedule CPU flexible events needlesslyAlexander Shishkin1-1/+5
In the sched-in path, we first remove a CPU's flexible events in order to give priority to the task's pinned events. However, this step can be safely skipped if the task doesn't have its own pinned events. This patch implements this skipping. Reported-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20170119164330.22887-2-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-30perf/core: Remove perf_cpu_context::unique_pmuDavid Carrillo-Cisneros2-31/+1
cpuctx->unique_pmu was originally introduced as a way to identify cpuctxs with shared pmus in order to avoid visiting the same cpuctx more than once in a for_each_pmu loop. cpuctx->unique_pmu == cpuctx->pmu in non-software task contexts since they have only one pmu per cpuctx. Since perf_pmu_sched_task() is only called in hw contexts, this patch replaces cpuctx->unique_pmu by cpuctx->pmu in it. The change above, together with the previous patch in this series, removed the remaining uses of cpuctx->unique_pmu, so we remove it altogether. Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Vince Weaver <vince@deater.net> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20170118192454.58008-3-davidcc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-30perf/core: Make cgroup switch visit only cpuctxs with cgroup eventsDavid Carrillo-Cisneros2-53/+46
This patch follows from a conversation in CQM/CMT's last series about speeding up the context switch for cgroup events: https://patchwork.kernel.org/patch/9478617/ This is a low-hanging fruit optimization. It replaces the iteration over the "pmus" list in cgroup switch by an iteration over a new list that contains only cpuctxs with at least one cgroup event. This is necessary because the number of PMUs have increased over the years e.g modern x86 server systems have well above 50 PMUs. The iteration over the full PMU list is unneccessary and can be costly in heavy cache contention scenarios. Below are some instrumentation measurements with 10, 50 and 90 percentiles of the total cost of context switch before and after this optimization for a simple array read/write microbenchark. Contention Level Nr events Before (us) After (us) Median L2 L3 types (10%, 50%, 90%) (10%, 50%, 90% Speedup -------------------------------------------------------------------------- Low Low 1 (1.72, 2.42, 5.85) (1.35, 1.64, 5.46) 29% High Low 1 (2.08, 4.56, 19.8) (1720, 2.20, 13.7) 51% High High 1 (2.86, 10.4, 12.7) (2.54, 4.32, 12.1) 58% Low Low 2 (1.98, 3.20, 6.89) (1.68, 2.41, 8.89) 24% High Low 2 (2.48, 5.28, 22.4) (2150, 3.69, 14.6) 30% High High 2 (3.32, 8.09, 13.9) (2.80, 5.15, 13.7) 36% where: 1 event type = cycles 2 event types = cycles,intel_cqm/llc_occupancy/ Contention L2 Low: workset < L2 cache size. High: " >> L2 " " . Contention L3 Low: workset of task on all sockets < L3 cache size. High: " " " " " " >> L3 " " . Median Speedup is (50%ile Before - 50%ile After) / 50%ile Before Unsurprisingly, the benefits of this optimization decrease with the number of cpuctxs with a cgroup events, yet, is never detrimental. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Vince Weaver <vince@deater.net> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20170118192454.58008-2-davidcc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-30perf/core: Fix PERF_RECORD_MMAP2 prot/flags for anonymous memoryPeter Zijlstra1-21/+21
Andres reported that MMAP2 records for anonymous memory always have their protection field 0. Turns out, someone daft put the prot/flags generation code in the file branch, leaving them unset for anonymous memory. Reported-by: Andres Freund <andres@anarazel.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Don Zickus <dzickus@redhat.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@gmail.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: anton@ozlabs.org Cc: namhyung@kernel.org Cc: stable@vger.kernel.org # v3.16+ Fixes: f972eb63b100 ("perf: Pass protection and flags bits through mmap2 interface") Link: http://lkml.kernel.org/r/20170126221508.GF6536@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-30perf/core: Fix use-after-free bugPeter Zijlstra1-2/+25
Dmitry reported a KASAN use-after-free on event->group_leader. It turns out there's a hole in perf_remove_from_context() due to event_function_call() not calling its function when the task associated with the event is already dead. In this case the event will have been detached from the task, but the grouping will have been retained, such that group operations might still work properly while there are live child events etc. This does however mean that we can miss a perf_group_detach() call when the group decomposes, this in turn can then lead to use-after-free. Fix it by explicitly doing the group detach if its still required. Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org # v4.5+ Cc: syzkaller <syzkaller@googlegroups.com> Fixes: 63b6da39bb38 ("perf: Fix perf_event_exit_task() race") Link: http://lkml.kernel.org/r/20170126153955.GD6515@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-29Linux 4.10-rc6Linus Torvalds1-2/+2
2017-01-29drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()Linus Torvalds1-0/+3
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-28parisc: Don't use BITS_PER_LONG in userspace-exported swab.h headerHelge Deller3-5/+10
In swab.h the "#if BITS_PER_LONG > 32" breaks compiling userspace programs if BITS_PER_LONG is #defined by userspace with the sizeof() compiler builtin. Solve this problem by using __BITS_PER_LONG instead. Since we now #include asm/bitsperlong.h avoid further potential userspace pollution by moving the #define of SHIFT_PER_LONG to bitops.h which is not exported to userspace. This patch unbreaks compiling qemu on hppa/parisc. Signed-off-by: Helge Deller <deller@gmx.de> Cc: <stable@vger.kernel.org>
2017-01-28parisc, parport_gsc: Fixes for printk continuation linesHelge Deller1-4/+4
Signed-off-by: Helge Deller <deller@gmx.de>
2017-01-27RDMA/cma: Fix unknown symbol when CONFIG_IPV6 is not enabledJack Morgenstein1-1/+2
If IPV6 has not been enabled in the underlying kernel, we must avoid calling IPV6 procedures in rdma_cm.ko. This requires using "IS_ENABLED(CONFIG_IPV6)" in "if" statements surrounding any code which calls external IPV6 procedures. In the instance fixed here, procedure cma_bind_addr() called ipv6_addr_type() -- which resulted in calling external procedure __ipv6_addr_type(). Fixes: 6c26a77124ff ("RDMA/cma: fix IPv6 address resolution") Cc: <stable@vger.kernel.org> # v4.2+ Cc: Spencer Baugh <sbaugh@catern.com> Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Reviewed-by: Moni Shoua <monis@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-01-27ARC: [arcompact] handle unaligned access delay slot corner caseVineet Gupta1-1/+2
After emulating an unaligned access in delay slot of a branch, we pretend as the delay slot never happened - so return back to actual branch target (or next PC if branch was not taken). Curently we did this by handling STATUS32.DE, we also need to clear the BTA.T bit, which is disregarded when returning from original misaligned exception, but could cause weirdness if it took the interrupt return path (in case interrupt was acive too) One ARC700 customer ran into this when enabling unaligned access fixup for kernel mode accesses as well Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-01-27xfs: prevent quotacheck from overloading inode lruBrian Foster1-1/+2
Quotacheck runs at mount time in situations where quota accounting must be recalculated. In doing so, it uses bulkstat to visit every inode in the filesystem. Historically, every inode processed during quotacheck was released and immediately tagged for reclaim because quotacheck runs before the superblock is marked active by the VFS. In other words, the final iput() lead to an immediate ->destroy_inode() call, which allowed the XFS background reclaim worker to start reclaiming inodes. Commit 17c12bcd3 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped") marks the XFS superblock active sooner as part of the mount process to support caching inodes processed during log recovery. This occurs before quotacheck and thus means all inodes processed by quotacheck are inserted to the LRU on release. The s_umount lock is held until the mount has completed and thus prevents the shrinkers from operating on the sb. This means that quotacheck can excessively populate the inode LRU and lead to OOM conditions on systems without sufficient RAM. Update the quotacheck bulkstat handler to set XFS_IGET_DONTCACHE on inodes processed by quotacheck. This causes ->drop_inode() to return 1 and in turn causes iput_final() to evict the inode. This preserves the original quotacheck behavior and prevents it from overloading the LRU and running out of memory. CC: stable@vger.kernel.org # v4.9 Reported-by: Martin Svec <martin.svec@zoner.cz> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-27ISDN: eicon: silence misleading array-bounds warningArnd Bergmann1-1/+2
With some gcc versions, we get a warning about the eicon driver, and that currently shows up as the only remaining warning in one of the build bots: In file included from ../drivers/isdn/hardware/eicon/message.c:30:0: eicon/message.c: In function 'mixer_notify_update': eicon/platform.h:333:18: warning: array subscript is above array bounds [-Warray-bounds] The code is easily changed to open-code the unusual PUT_WORD() line causing this to avoid the warning. Cc: stable@vger.kernel.org Link: http://arm-soc.lixom.net/buildlogs/stable-rc/v4.4.45/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27net: phy: micrel: add support for KSZ8795Sean Nyekjaer2-0/+16
This is adds support for the PHYs in the KSZ8795 5port managed switch. It will allow to detect the link between the switch and the soc and uses the same read_status functions as the KSZ8873MLL switch. Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27gtp: fix cross netns recv on gtp socketAndreas Schultz1-6/+4
The use of the passed through netlink src_net to check for a cross netns operation was wrong. Using the GTP socket and the GTP netdevice is always correct (even if the netdev has been moved to new netns after link creation). Remove the now obsolete net field from gtp_dev. Signed-off-by: Andreas Schultz <aschultz@tpip.net> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27gtp: clear DF bit on GTP packet txAndreas Schultz1-1/+1
3GPP TS 29.281 and 3GPP TS 29.060 imply that GTP-U packets should be sent with the DF bit cleared. For example 3GPP TS 29.060, Release 8, Section 13.2.2: > Backbone router: Any router in the backbone may fragment the GTP > packet if needed, according to IPv4. Signed-off-by: Andreas Schultz <aschultz@tpip.net> Acked-by: Harald Welte <laforge@netfilter.org> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27gtp: add genl family modules aliasAndreas Schultz1-0/+1
Auto-load the module when userspace asks for the gtp netlink family. Signed-off-by: Andreas Schultz <aschultz@tpip.net> Acked-by: Harald Welte <laforge@netfilter.org> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27tcp: don't annotate mark on control socket from tcp_v6_send_response()Pablo Neira6-10/+10
Unlike ipv4, this control socket is shared by all cpus so we cannot use it as scratchpad area to annotate the mark that we pass to ip6_xmit(). Add a new parameter to ip6_xmit() to indicate the mark. The SCTP socket family caches the flowi6 structure in the sctp_transport structure, so we cannot use to carry the mark unless we later on reset it back, which I discarded since it looks ugly to me. Fixes: bf99b4ded5f8 ("tcp: fix mark propagation with fwmark_reflect enabled") Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27arm64: skip register_cpufreq_notifier on ACPI-based systemsPrashanth Prakash1-1/+7
On ACPI based systems where the topology is setup using the API store_cpu_topology, at the moment we do not have necessary code to parse cpu capacity and handle cpufreq notifier, thus resulting in a kernel panic. Stack: init_cpu_capacity_callback+0xb4/0x1c8 notifier_call_chain+0x5c/0xa0 __blocking_notifier_call_chain+0x58/0xa0 blocking_notifier_call_chain+0x3c/0x50 cpufreq_set_policy+0xe4/0x328 cpufreq_init_policy+0x80/0x100 cpufreq_online+0x418/0x710 cpufreq_add_dev+0x118/0x180 subsys_interface_register+0xa4/0xf8 cpufreq_register_driver+0x1c0/0x298 cppc_cpufreq_init+0xdc/0x1000 [cppc_cpufreq] do_one_initcall+0x5c/0x168 do_init_module+0x64/0x1e4 load_module+0x130c/0x14d0 SyS_finit_module+0x108/0x120 el0_svc_naked+0x24/0x28 Fixes: 7202bde8b7ae ("arm64: parse cpu capacity-dmips-mhz from DT") Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-01-27drm/nouveau: Handle fbcon suspend/resume in seperate workerLyude Paul2-9/+36
Resuming from RPM can happen while already holding dev->mode_config.mutex. This means we can't actually handle fbcon in any RPM resume workers, since restoring fbcon requires grabbing dev->mode_config.mutex again. So move the fbcon suspend/resume code into it's own worker, and rely on that instead to avoid deadlocking. This fixes more deadlocks for runtime suspending the GPU on the ThinkPad W541. Reproduction recipe: - Get a machine with both optimus and a nvidia card with connectors attached to it - Wait for the nvidia GPU to suspend - Attempt to manually reprobe any of the connectors on the nvidia GPU using sysfs - *deadlock* [airlied: use READ_ONCE to address Hans's comment] Signed-off-by: Lyude <lyude@redhat.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Kilian Singer <kilian.singer@quantumtechnology.info> Cc: Lukas Wunner <lukas@wunner.de> Cc: David Airlie <airlied@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2017-01-27drm/nouveau: Don't enabling polling twice on runtime resumeLyude Paul2-2/+6
As it turns out, on cards that actually have CRTCs on them we're already calling drm_kms_helper_poll_enable(drm_dev) from nouveau_display_resume() before we call it in nouveau_pmops_runtime_resume(). This leads us to accidentally trying to enable polling twice, which results in a potential deadlock between the RPM locks and drm_dev->mode_config.mutex if we end up trying to enable polling the second time while output_poll_execute is running and holding the mode_config lock. As such, make sure we only enable polling in nouveau_pmops_runtime_resume() if we need to. This fixes hangs observed on the ThinkPad W541 Signed-off-by: Lyude <lyude@redhat.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Kilian Singer <kilian.singer@quantumtechnology.info> Cc: Lukas Wunner <lukas@wunner.de> Cc: David Airlie <airlied@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2017-01-27drm/ast: Fixed system hanged if disable P2AY.C. Chen3-79/+97
The original ast driver will access some BMC configuration through P2A bridge that can be disabled since AST2300 and after. It will cause system hanged if P2A bridge is disabled. Here is the update to fix it. Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2017-01-26Btrfs: remove ->{get, set}_acl() from btrfs_dir_ro_inode_operationsOmar Sandoval1-2/+0
Subvolume directory inodes can't have ACLs. Cc: <stable@vger.kernel.org> # 4.9.x Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
2017-01-26Btrfs: disable xattr operations on subvolume directoriesOmar Sandoval1-0/+1
When you snapshot a subvolume containing a subvolume, you get a placeholder directory where the subvolume would be. These directory inodes have ->i_ops set to btrfs_dir_ro_inode_operations. Previously, these i_ops didn't include the xattr operation callbacks. The conversion to xattr_handlers missed this case, leading to bogus attempts to set xattrs on these inodes. This manifested itself as failures when running delayed inodes. To fix this, clear IOP_XATTR in ->i_opflags on these inodes. Fixes: 6c6ef9f26e59 ("xattr: Stop calling {get,set,remove}xattr inode operations") Cc: Andreas Gruenbacher <agruenba@redhat.com> Reported-by: Chris Murphy <lists@colorremedies.com> Tested-by: Chris Murphy <lists@colorremedies.com> Cc: <stable@vger.kernel.org> # 4.9.x Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
2017-01-26Btrfs: remove old tree_root case in btrfs_read_locked_inode()Omar Sandoval1-4/+1
As Jeff explained in c2951f32d36c ("btrfs: remove old tree_root dirent processing in btrfs_real_readdir()"), supporting this old format is no longer necessary since the Btrfs magic number has been updated since we changed to the current format. There are other places where we still handle this old format, but since this is part of a fix that is going to stable, I'm only removing this one for now. Cc: <stable@vger.kernel.org> # 4.9.x Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
2017-01-26ravb: unmap descriptors when freeing ringsKazuya Mizuguchi1-48/+64
"swiotlb buffer is full" errors occur after repeated initialisation of a device - f.e. suspend/resume or ip link set up/down. This is because memory mapped using dma_map_single() in ravb_ring_format() and ravb_start_xmit() is not released. Resolve this problem by unmapping descriptors when freeing rings. Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com> [simon: reworked] Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-26pNFS: Fix a reference leak in _pnfs_return_layoutTrond Myklebust1-1/+1
IF NFS_LAYOUT_RETURN_REQUESTED is not set, then we currently exit without freeing the list of invalidated layout segments, leading to a reference leak. Reported-by: Olga Kornievskaia <aglo@umich.edu> Fixes: 24408f5282 ("pNFS: Fix bugs in _pnfs_return_layout") Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-26nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"Chuck Lever1-0/+1
Lock sequence IDs are bumped in decode_lock by calling nfs_increment_seqid(). nfs_increment_sequid() does not use the seqid_mutating_err() function fixed in commit 059aa7348241 ("Don't increment lock sequence ID after NFS4ERR_MOVED"). Fixes: 059aa7348241 ("Don't increment lock sequence ID after ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Xuan Qi <xuan.qi@oracle.com> Cc: stable@vger.kernel.org # v3.7+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-26xfs: fix bmv_count confusion w/ shared extentsDarrick J. Wong1-10/+18
In a bmapx call, bmv_count is the total size of the array, including the zeroth element that userspace uses to supply the search key. The output array starts at offset 1 so that we can set up the user for the next invocation. Since we now can split an extent into multiple bmap records due to shared/unshared status, we have to be careful that we don't overflow the output array. In the original patch f86f403794b ("xfs: teach get_bmapx about shared extents and the CoW fork") I used cur_ext (the output index) to check for overflows, albeit with an off-by-one error. Since nexleft no longer describes the number of unfilled slots in the output, we can rip all that out and use cur_ext for the overflow check directly. Failure to do this causes heap corruption in bmapx callers such as xfs_io and xfs_scrub. xfs/328 can reproduce this problem. Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-26sysctl: fix proc_doulongvec_ms_jiffies_minmax()Eric Dumazet1-0/+1
We perform the conversion between kernel jiffies and ms only when exporting kernel value to user space. We need to do the opposite operation when value is written by user. Only matters when HZ != 1000 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-26Revert "sd: remove __data_len hack for WRITE SAME"Bart Van Assche1-1/+16
This patch reverts commit f80de881d8df and avoids that sending a WRITE SAME command to the iSCSI initiator triggers the following: BUG: unable to handle kernel NULL pointer dereference at 0000000000000014 TARGET_CORE[iSCSI]: Expected Transfer Length: 260096 does not match SCSI CDB Length: 512 for SAM Opcode: 0x41 IP: iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp] Oops: 0000 [#1] SMP Modules linked in: target_core_user uio target_core_iblock target_core_file iscsi_target_mod target_core_mod netconsole configfs crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 crypto_simd cryptd glue_helper virtio_console virtio_rng virtio_balloon serio_raw i2c_piix4 acpi_cpufreq button iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ext4 jbd2 mbcache virtio_blk virtio_net psmouse floppy drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_pci CPU: 2 PID: 5 Comm: kworker/u8:0 Not tainted 4.10.0-rc5-debug+ #3 Workqueue: iscsi_q_0 iscsi_xmitworker [libiscsi] RIP: 0010:iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp] Call Trace: iscsi_sw_tcp_xmit_segment+0x84/0x120 [iscsi_tcp] iscsi_sw_tcp_pdu_xmit+0x51/0x180 [iscsi_tcp] iscsi_tcp_task_xmit+0xb3/0x290 [libiscsi_tcp] iscsi_xmit_task+0x4e/0xc0 [libiscsi] iscsi_xmitworker+0x243/0x330 [libiscsi] process_one_work+0x1d8/0x4b0 worker_thread+0x49/0x4a0 kthread+0x102/0x140 Fixes: f80de881d8df ("sd: remove __data_len hack for WRITE SAME") Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Hannes Reinecke <hare@suse.com> Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Jens Axboe <axboe@fb.com> Cc: Lee Duncan <lduncan@suse.com> Cc: Chris Leech <cleech@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-26nvme-fc: use blk_rq_nr_phys_segmentsChristoph Hellwig1-3/+3
Without this deallocate won't work properly due to the mismatch of the bio/request size and the actual payload size. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Smart <james.smart@broadcom.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-01-26nvmet-rdma: Fix missing dma sync to nvme data structuresParav Pandit1-0/+17
This patch performs dma sync operations on nvme_command and nvme_completion. nvme_command is synced (a) on receiving of the recv queue completion for cpu access. (b) before posting recv wqe back to rdma adapter for device access. nvme_completion is synced (a) on receiving of the recv queue completion of associated nvme_command for cpu access. (b) before posting send wqe to rdma adapter for device access. This patch is generated for git://git.infradead.org/nvme-fabrics.git Branch: nvmf-4.10 Signed-off-by: Parav Pandit <parav@mellanox.com> Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
2017-01-26nvmet: Call fatal_error from keep-alive timout expirationSagi Grimberg1-1/+1
We only need to call delete_ctrl once, so given that both keep-alive timeout and any other fatal error can trigger it, just make sure we only call delete_ctrl once. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet: cancel fatal error and flush async work before free controllerSagi Grimberg1-0/+3
Make sure they are not running and we can free the controller safely. Signed-off-by: Roy Shterman <roys@lightbitslabs.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet: delete controllers deletion upon subsystem releaseSagi Grimberg3-0/+12
No reason for them to be kept around if we are deleting the subsystem, so instead of passively wait for the host to disconnect, actively delete the controllers. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet_fc: correct logic in disconnect queue LS handlingJames Smart1-14/+22
Correct logic in disconnect queue LS handling. Rework so that queue searching and error reporting is above the section to send back a ls rjt Signed-off-by: James Smart <james.smart@broadcom.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-01-26perf ftrace: Make 'function_graph' be the default tracerArnaldo Carvalho de Melo1-1/+2
So that we can suppress the '-t function_graph' and get a more compact command line: # perf ftrace usleep 123456 | grep raw_spin_lock | sort -k2 -nr | head -5 2) 0.555 us | _raw_spin_lock(); 2) 0.516 us | _raw_spin_lock(); 2) 0.410 us | _raw_spin_lock_irq(); 2) 0.374 us | _raw_spin_lock_irqsave(); # Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Eder <jeder@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ss9xgx5htpxcv86x42pnh3m6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf ftrace: Introduce new 'ftrace' toolNamhyung Kim6-0/+282
The 'perf ftrace' command is a simple wrapper of kernel's ftrace functionality. It only supports single thread tracing currently and just reads trace_pipe in text and then write it to stdout. Committer notes: Testing it: # perf ftrace -f function_graph usleep 123456 <SNIP> 2) | SyS_nanosleep() { 2) | _copy_from_user() { <SNIP> 2) 0.900 us | } 2) 1.354 us | } 2) | hrtimer_nanosleep() { 2) 0.062 us | __hrtimer_init(); 2) | do_nanosleep() { 2) | hrtimer_start_range_ns() { <SNIP> 2) 5.025 us | } 2) | schedule() { 2) 0.125 us | rcu_note_context_switch(); 2) 0.057 us | _raw_spin_lock(); 2) | deactivate_task() { 2) 0.369 us | update_rq_clock.part.77(); 2) | dequeue_task_fair() { <SNIP> 2) + 22.453 us | } 2) + 23.736 us | } 2) | pick_next_task_fair() { <SNIP> 2) + 47.167 us | } 2) | pick_next_task_idle() { <SNIP> 2) 4.462 us | } ------------------------------------------ 2) usleep-20387 => <idle>-0 ------------------------------------------ 2) 0.806 us | switch_mm_irqs_off(); ------------------------------------------ 2) <idle>-0 => usleep-20387 ------------------------------------------ 2) 0.151 us | finish_task_switch(); 2) @ 123597.2 us | } 2) 0.037 us | _cond_resched(); 2) | hrtimer_try_to_cancel() { 2) 0.064 us | hrtimer_active(); 2) 0.353 us | } 2) @ 123605.3 us | } 2) @ 123606.2 us | } 2) @ 123608.3 us | } /* SyS_nanosleep */ 2) | __do_page_fault() { <SNIP> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Eder <jeder@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com>, Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-r1hgmsj4dxny8arn3o9mw512@git.kernel.org [ Various foward port fixes, add man page ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf util: Add more debug message on failure pathNamhyung Kim2-18/+39
It's helpful for debugging on tracing features. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Eder <jeder@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com>, Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-rjysr9ljiesymgk4qblteaty@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf util: Save pid-cmdline mapping into tracing headerNamhyung Kim4-3/+84
Current trace info data lacks the saved cmdline mapping which is needed for pevent to find out the comm of a task. Add this and bump up the version number so that perf can determine its presence when reading. This is mostly corresponding to trace.dat file version 6, but still lacks 4 byte of number of cpus, and 10 bytes of type string - and I think we don't need those anyway. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Eder <jeder@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com>, Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> [ Change version test from == to >= ] Link: http://lkml.kernel.org/n/tip-vaooqpxsikxbb3359p0corcb@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf scripting perl: Do not die() when not founding event for a typeArnaldo Carvalho de Melo1-2/+4
Do just like handling other cases i.e. print some debug message and ignore the sample. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-t7kzlm3cxyvbd7d9n9554ai9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26tools lib bpf: Add libbpf_get_error()Joe Stringer3-2/+12
This function will turn a libbpf pointer into a standard error code (or 0 if the pointer is valid). This also allows removal of the dependency on linux/err.h in the public header file, which causes problems in userspace programs built against libbpf. Signed-off-by: Joe Stringer <joe@ovn.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170123011128.26534-5-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26tools lib bpf: Add set/is helpers for all prog typesJoe Stringer2-0/+15
These bpf_prog_types were exposed in the uapi but there were no corresponding functions to set these types for programs in libbpf. Signed-off-by: Joe Stringer <joe@ovn.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170123011128.26534-4-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26tools lib bpf: Define prog_type fns with macroJoe Stringer1-25/+16
Turning this into a macro allows future prog types to be added with a single line per type. Signed-off-by: Joe Stringer <joe@ovn.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170123011128.26534-3-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26tools lib bpf: Fix map offsets in relocationJoe Stringer1-3/+12
Commit 4708bbda5cb2 ("tools lib bpf: Fix maps resolution") attempted to fix map resolution by identifying the number of symbols that point to maps, and using this number to resolve each of the maps. However, during relocation the original definition of the map size was still in use. For up to two maps, the calculation was correct if there was a small difference in size between the map definition in libbpf and the one that the client library uses. However if the difference was large, particularly if more than two maps were used in the BPF program, the relocation would fail. For example, when using a map definition with size 28, with three maps, map relocation would count: (sym_offset / sizeof(struct bpf_map_def) => map_idx) (0 / 16 => 0), ie map_idx = 0 (28 / 16 => 1), ie map_idx = 1 (56 / 16 => 3), ie map_idx = 3 So, libbpf reports: libbpf: bpf relocation: map_idx 3 large than 2 Fix map relocation by checking the exact offset of maps when doing relocation. Signed-off-by: Joe Stringer <joe@ovn.org> [Allow different map size in an object] Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: netdev@vger.kernel.org Fixes: 4708bbda5cb2 ("tools lib bpf: Fix maps resolution") Link: http://lkml.kernel.org/r/20170123011128.26534-2-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf probe: Delete an unnecessary assignment in try_to_find_absolute_address()Markus Elfring1-3/+2
Remove an error code assignment which is redundant in an if branch for the handling of a memory allocation failure because the same value was set for the local variable "err" before. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: kernel-janitors@vger.kernel.org Link: http://lkml.kernel.org/r/0ede09ec-79b6-c8bd-5b20-02c63ed98aab@users.sourceforge.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf probe: Delete an unnecessary check in try_to_find_absolute_address()Markus Elfring1-4/+2
Remove a condition check which is unnecessary at the end because this source code place should usually only be reached with a non-zero pointer. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: kernel-janitors@vger.kernel.org Link: http://lkml.kernel.org/r/a3f2473b-6383-a326-bce0-b826423608b8@users.sourceforge.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26perf probe: Fix wrong register name for arm64He Kuang1-6/+6
The register name of arm64 architecture is x0-x31 not r0-r31, this patch changes this typo. Before this patch: # perf probe --definition 'sys_write count' p:probe/sys_write _text+1502872 count=%r2:s64 # echo 'p:probe/sys_write _text+1502872 count=%r2:s64' > \ /sys/kernel/debug/tracing/kprobe_events Parse error at argument[0]. (-22) After this patch: # perf probe --definition 'sys_write count' p:probe/sys_write _text+1502872 count=%x2:s64 # echo 'p:probe/sys_write _text+1502872 count=%x2:s64' > \ /sys/kernel/debug/tracing/kprobe_events # echo 1 >/sys/kernel/debug/tracing/events/probe/enable # cat /sys/kernel/debug/tracing/trace ... sh-422 [000] d... 650.495930: sys_write: (SyS_write+0x0/0xc8) count=22 sh-422 [000] d... 651.102389: sys_write: (SyS_write+0x0/0xc8) count=26 sh-422 [000] d... 651.358653: sys_write: (SyS_write+0x0/0xc8) count=86 Signed-off-by: He Kuang <hekuang@huawei.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Bintian Wang <bintian.wang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/20170124103015.1936-2-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-25xfs: clear _XBF_PAGES from buffers when readahead pageDarrick J. Wong1-0/+1
If we try to allocate memory pages to back an xfs_buf that we're trying to read, it's possible that we'll be so short on memory that the page allocation fails. For a blocking read we'll just wait, but for readahead we simply dump all the pages we've collected so far. Unfortunately, after dumping the pages we neglect to clear the _XBF_PAGES state, which means that the subsequent call to xfs_buf_free thinks that b_pages still points to pages we own. It then double-frees the b_pages pages. This results in screaming about negative page refcounts from the memory manager, which xfs oughtn't be triggering. To reproduce this case, mount a filesystem where the size of the inodes far outweighs the availalble memory (a ~500M inode filesystem on a VM with 300MB memory did the trick here) and run bulkstat in parallel with other memory eating processes to put a huge load on the system. The "check summary" phase of xfs_scrub also works for this purpose. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com>