kernel/linux.git, branch v4.9.156

Linux 4.9.156

2019-02-12T18:45:02+00:00

ath9k: dynack: check da->enabled first in sampling routines

2019-02-12T18:45:02+00:00

commit 9d3d65a91f027b8a9af5e63752d9b78cb10eb92d upstream. Check da->enabled flag first in ath_dynack_sample_tx_ts and ath_dynack_sample_ack_ts routines in order to avoid useless processing Tested-by: Koen Vandeputte Signed-off-by: Lorenzo Bianconi Signed-off-by: Kalle Valo Signed-off-by: Greg Kroah-Hartman

ath9k: dynack: make ewma estimation faster

2019-02-12T18:45:02+00:00

commit 0c60c490830a1a756c80f8de8d33d9c6359d4a36 upstream. In order to make propagation time estimation faster, use current sample as ewma output value during 'late ack' tracking Tested-by: Koen Vandeputte Signed-off-by: Lorenzo Bianconi Signed-off-by: Kalle Valo Signed-off-by: Greg Kroah-Hartman

perf/x86/intel: Delay memory deallocation until x86_pmu_dead_cpu()

2019-02-12T18:45:02+00:00

commit 602cae04c4864bb3487dfe4c2126c8d9e7e1614a upstream. intel_pmu_cpu_prepare() allocated memory for ->shared_regs among other members of struct cpu_hw_events. This memory is released in intel_pmu_cpu_dying() which is wrong. The counterpart of the intel_pmu_cpu_prepare() callback is x86_pmu_dead_cpu(). Otherwise if the CPU fails on the UP path between CPUHP_PERF_X86_PREPARE and CPUHP_AP_PERF_X86_STARTING then it won't release the memory but allocate new memory on the next attempt to online the CPU (leaking the old memory). Also, if the CPU down path fails between CPUHP_AP_PERF_X86_STARTING and CPUHP_PERF_X86_PREPARE then the CPU will go back online but never allocate the memory that was released in x86_pmu_dying_cpu(). Make the memory allocation/free symmetrical in regard to the CPU hotplug notifier by moving the deallocation to intel_pmu_cpu_dead(). This started in commit: a7e3ed1e47011 ("perf: Add support for supplementary event registers"). In principle the bug was introduced in v2.6.39 (!), but it will almost certainly not backport cleanly across the big CPU hotplug rewrite between v4.7-v4.15... [ bigeasy: Added patch description. ] [ mingo: Added backporting guidance. ] Reported-by: He Zhe Signed-off-by: Peter Zijlstra (Intel) # With developer hat on Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) # With maintainer hat on Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: acme@kernel.org Cc: bp@alien8.de Cc: hpa@zytor.com Cc: jolsa@kernel.org Cc: kan.liang@linux.intel.com Cc: namhyung@kernel.org Cc: Fixes: a7e3ed1e47011 ("perf: Add support for supplementary event registers"). Link: https://lkml.kernel.org/r/20181219165350.6s3jvyxbibpvlhtq@linutronix.de Signed-off-by: Ingo Molnar [ He Zhe: Fixes conflict caused by missing disable_counter_freeze which is introduced since v4.20 af3bdb991a5cb. ] Signed-off-by: He Zhe Signed-off-by: Greg Kroah-Hartman

IB/hfi1: Add limit test for RC/UC send via loopback

2019-02-12T18:45:02+00:00

commit 09ce351dff8e7636af0beb72cd4a86c3904a0500 upstream. Fix potential memory corruption and panic in loopback for IB_WR_SEND variants. The code blindly assumes the posted length will fit in the fetched rwqe, which is not a valid assumption. Fix by adding a limit test, and triggering the appropriate send completion and putting the QP in an error state. This mimics the handling for non-loopback QPs. Fixes: 15703461533a ("IB/{hfi1, qib, rdmavt}: Move ruc_loopback to rdmavt") Cc: #v4.20+ Reviewed-by: Michael J. Ruhl Signed-off-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro Signed-off-by: Jason Gunthorpe Signed-off-by: Greg Kroah-Hartman Signed-off-by: Mike Marciniszyn

PCI: vmd: Free up IRQs on suspend path

2019-02-12T18:45:02+00:00

commit e2b1820bd5d0962d6f271b0d47c3a0e38647df2f upstream. Free up the IRQs we request on the suspend path and reallocate them on the resume path. Fixes this error: CPU 111 disable failed: CPU has 9 vectors assigned and there are only 0 available. Error taking CPU111 down: -34 Non-boot CPUs are not disabled Enabling non-boot CPUs ... Signed-off-by: Scott Bauer Signed-off-by: Bjorn Helgaas Acked-by: Keith Busch Signed-off-by: Greg Kroah-Hartman Reviewed-by: Jon Derrick Signed-off-by: Sushma Kalakota

oom, oom_reaper: do not enqueue same task twice

2019-02-12T18:45:02+00:00

commit 9bcdeb51bd7d2ae9fe65ea4d60643d2aeef5bfe3 upstream. Arkadiusz reported that enabling memcg's group oom killing causes strange memcg statistics where there is no task in a memcg despite the number of tasks in that memcg is not 0. It turned out that there is a bug in wake_oom_reaper() which allows enqueuing same task twice which makes impossible to decrease the number of tasks in that memcg due to a refcount leak. This bug existed since the OOM reaper became invokable from task_will_free_mem(current) path in out_of_memory() in Linux 4.7, T1@P1 |T2@P1 |T3@P1 |OOM reaper ----------+----------+----------+------------ # Processing an OOM victim in a different memcg domain. try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) out_of_memory() oom_kill_process(P1) do_send_sig_info(SIGKILL, @P1) mark_oom_victim(T1@P1) wake_oom_reaper(T1@P1) # T1@P1 is enqueued. mutex_unlock(&oom_lock) out_of_memory() mark_oom_victim(T2@P1) wake_oom_reaper(T2@P1) # T2@P1 is enqueued. mutex_unlock(&oom_lock) out_of_memory() mark_oom_victim(T1@P1) wake_oom_reaper(T1@P1) # T1@P1 is enqueued again due to oom_reaper_list == T2@P1 && T1@P1->oom_reaper_list == NULL. mutex_unlock(&oom_lock) # Completed processing an OOM victim in a different memcg domain. spin_lock(&oom_reaper_lock) # T1P1 is dequeued. spin_unlock(&oom_reaper_lock) but memcg's group oom killing made it easier to trigger this bug by calling wake_oom_reaper() on the same task from one out_of_memory() request. Fix this bug using an approach used by commit 855b018325737f76 ("oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task"). As a side effect of this patch, this patch also avoids enqueuing multiple threads sharing memory via task_will_free_mem(current) path. Link: http://lkml.kernel.org/r/e865a044-2c10-9858-f4ef-254bc71d6cc2@i-love.sakura.ne.jp Link: http://lkml.kernel.org/r/5ee34fc6-1485-34f8-8790-903ddabaa809@i-love.sakura.ne.jp Fixes: af8e15cc85a25315 ("oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head") Signed-off-by: Tetsuo Handa Reported-by: Arkadiusz Miskiewicz Tested-by: Arkadiusz Miskiewicz Acked-by: Michal Hocko Acked-by: Roman Gushchin Cc: Tejun Heo Cc: Aleksa Sarai Cc: Jay Kamat Cc: Johannes Weiner Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

serial: fix race between flush_to_ldisc and tty_open

2019-02-12T18:45:02+00:00

commit fedb5760648a291e949f2380d383b5b2d2749b5e upstream. There still is a race window after the commit b027e2298bd588 ("tty: fix data race between tty_init_dev and flush of buf"), and we encountered this crash issue if receive_buf call comes before tty initialization completes in tty_open and tty->driver_data may be NULL. CPU0 CPU1 ---- ---- tty_open tty_init_dev tty_ldisc_unlock schedule flush_to_ldisc receive_buf tty_port_default_receive_buf tty_ldisc_receive_buf n_tty_receive_buf_common __receive_buf uart_flush_chars uart_start /*tty->driver_data is NULL*/ tty->ops->open /*init tty->driver_data*/ it can be fixed by extending ldisc semaphore lock in tty_init_dev to driver_data initialized completely after tty->ops->open(), but this will lead to get lock on one function and unlock in some other function, and hard to maintain, so fix this race only by checking tty->driver_data when receiving, and return if tty->driver_data is NULL, and n_tty_receive_buf_common maybe calls uart_unthrottle, so add the same check. Because the tty layer knows nothing about the driver associated with the device, the tty layer can not do anything here, it is up to the tty driver itself to check for this type of race. Fix up the serial driver to correctly check to see if it is finished binding with the device when being called, and if not, abort the tty calls. [Description and problem report and testing from Li RongQing, I rewrote the patch to be in the serial layer, not in the tty core - gregkh] Reported-by: Li RongQing Tested-by: Li RongQing Signed-off-by: Wang Li Signed-off-by: Zhang Yu Signed-off-by: Li RongQing Cc: stable Signed-off-by: Greg Kroah-Hartman

perf tests evsel-tp-sched: Fix bitwise operator

2019-02-12T18:45:02+00:00

commit 489338a717a0dfbbd5a3fabccf172b78f0ac9015 upstream. Notice that the use of the bitwise OR operator '|' always leads to true in this particular case, which seems a bit suspicious due to the context in which this expression is being used. Fix this by using bitwise AND operator '&' instead. This bug was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields") Link: http://lkml.kernel.org/r/20190122233439.GA5868@embeddedor Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf/core: Don't WARN() for impossible ring-buffer sizes

2019-02-12T18:45:01+00:00

commit 9dff0aa95a324e262ffb03f425d00e4751f3294e upstream. The perf tool uses /proc/sys/kernel/perf_event_mlock_kb to determine how large its ringbuffer mmap should be. This can be configured to arbitrary values, which can be larger than the maximum possible allocation from kmalloc. When this is configured to a suitably large value (e.g. thanks to the perf fuzzer), attempting to use perf record triggers a WARN_ON_ONCE() in __alloc_pages_nodemask(): WARNING: CPU: 2 PID: 5666 at mm/page_alloc.c:4511 __alloc_pages_nodemask+0x3f8/0xbc8 Let's avoid this by checking that the requested allocation is possible before calling kzalloc. Reported-by: Julien Thierry Signed-off-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Julien Thierry Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Link: https://lkml.kernel.org/r/20190110142745.25495-1-mark.rutland@arm.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman