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* quota: fix wrong condition in is_quota_modification()Chao Yu2019-10-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6565c182094f69e4ffdece337d395eb7ec760efc upstream. Quoted from commit 3da40c7b0898 ("ext4: only call ext4_truncate when size <= isize") " At LSF we decided that if we truncate up from isize we shouldn't trim fallocated blocks that were fallocated with KEEP_SIZE and are past the new i_size. This patch fixes ext4 to do this. " And generic/092 of fstest have covered this case for long time, however is_quota_modification() didn't adjust based on that rule, so that in below condition, we will lose to quota block change: - fallocate blocks beyond EOF - remount - truncate(file_path, file_size) Fix it. Link: https://lore.kernel.org/r/20190911093650.35329-1-yuchao0@huawei.com Fixes: 3da40c7b0898 ("ext4: only call ext4_truncate when size <= isize") CC: stable@vger.kernel.org Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* blk-mq: add callback of .cleanup_rqMing Lei2019-10-051-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 226b4fc75c78f9c497c5182d939101b260cfb9f3 ] SCSI maintains its own driver private data hooked off of each SCSI request, and the pridate data won't be freed after scsi_queue_rq() returns BLK_STS_RESOURCE or BLK_STS_DEV_RESOURCE. An upper layer driver (e.g. dm-rq) may need to retry these SCSI requests, before SCSI has fully dispatched them, due to a lower level SCSI driver's resource limitation identified in scsi_queue_rq(). Currently SCSI's per-request private data is leaked when the upper layer driver (dm-rq) frees and then retries these requests in response to BLK_STS_RESOURCE or BLK_STS_DEV_RESOURCE returns from scsi_queue_rq(). This usecase is so specialized that it doesn't warrant training an existing blk-mq interface (e.g. blk_mq_free_request) to allow SCSI to account for freeing its driver private data -- doing so would add an extra branch for handling a special case that all other consumers of SCSI (and blk-mq) won't ever need to worry about. So the most pragmatic way forward is to delegate freeing SCSI driver private data to the upper layer driver (dm-rq). Do so by adding new .cleanup_rq callback and calling a new blk_mq_cleanup_rq() method from dm-rq. A following commit will implement the .cleanup_rq() hook in scsi_mq_ops. Cc: Ewan D. Milne <emilne@redhat.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: <stable@vger.kernel.org> Fixes: 396eaf21ee17 ("blk-mq: improve DM's blk-mq IO merging via blk_insert_cloned_request feedback") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* mmc: core: Add helper function to indicate if SDIO IRQs is enabledUlf Hansson2019-10-051-0/+9
| | | | | | | | | | | | | | | | | | | [ Upstream commit bd880b00697befb73eff7220ee20bdae4fdd487b ] To avoid each host driver supporting SDIO IRQs, from keeping track internally about if SDIO IRQs has been claimed, let's introduce a common helper function, sdio_irq_claimed(). The function returns true if SDIO IRQs are claimed, via using the information about the number of claimed irqs. This is safe, even without any locks, as long as the helper function is called only from runtime/system suspend callbacks of the host driver. Tested-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* kprobes: Prohibit probing on BUG() and WARN() addressMasami Hiramatsu2019-10-051-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit e336b4027775cb458dc713745e526fa1a1996b2a ] Since BUG() and WARN() may use a trap (e.g. UD2 on x86) to get the address where the BUG() has occurred, kprobes can not do single-step out-of-line that instruction. So prohibit probing on such address. Without this fix, if someone put a kprobe on WARN(), the kernel will crash with invalid opcode error instead of outputing warning message, because kernel can not find correct bug address. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S . Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naveen N . Rao <naveen.n.rao@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/156750890133.19112.3393666300746167111.stgit@devnote2 Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* gpio: don't WARN() on NULL descs if gpiolib is disabledBartosz Golaszewski2019-09-161-31/+31
| | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit ffe0bbabb0cffceceae07484fde1ec2a63b1537c ] If gpiolib is disabled, we use the inline stubs from gpio/consumer.h instead of regular definitions of GPIO API. The stubs for 'optional' variants of gpiod_get routines return NULL in this case as if the relevant GPIO wasn't found. This is correct so far. Calling other (non-gpio_get) stubs from this header triggers a warning because the GPIO descriptor couldn't have been requested. The warning however is unconditional (WARN_ON(1)) and is emitted even if the passed descriptor pointer is NULL. We don't want to force the users of 'optional' gpio_get to check the returned pointer before calling e.g. gpiod_set_value() so let's only WARN on non-NULL descriptors. Cc: stable@vger.kernel.org Reported-by: Claus H. Stovgaard <cst@phaseone.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* dm mpath: fix missing call of path selector type->end_ioYufen Yu2019-09-161-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 5de719e3d01b4abe0de0d7b857148a880ff2a90b ] After commit 396eaf21ee17 ("blk-mq: improve DM's blk-mq IO merging via blk_insert_cloned_request feedback"), map_request() will requeue the tio when issued clone request return BLK_STS_RESOURCE or BLK_STS_DEV_RESOURCE. Thus, if device driver status is error, a tio may be requeued multiple times until the return value is not DM_MAPIO_REQUEUE. That means type->start_io may be called multiple times, while type->end_io is only called when IO complete. In fact, even without commit 396eaf21ee17, setup_clone() failure can also cause tio requeue and associated missed call to type->end_io. The service-time path selector selects path based on in_flight_size, which is increased by st_start_io() and decreased by st_end_io(). Missed calls to st_end_io() can lead to in_flight_size count error and will cause the selector to make the wrong choice. In addition, queue-length path selector will also be affected. To fix the problem, call type->end_io in ->release_clone_rq before tio requeue. map_info is passed to ->release_clone_rq() for map_request() error path that result in requeue. Fixes: 396eaf21ee17 ("blk-mq: improve DM's blk-mq IO merging via blk_insert_cloned_request feedback") Cc: stable@vger.kernl.org Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* libceph: allow ceph_buffer_put() to receive a NULL ceph_bufferLuis Henriques2019-09-101-1/+2
| | | | | | | | | [ Upstream commit 5c498950f730aa17c5f8a2cdcb903524e4002ed2 ] Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* gpio: Fix build error of function redefinitionYueHaibing2019-09-101-24/+0
| | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 68e03b85474a51ec1921b4d13204782594ef7223 ] when do randbuilding, I got this error: In file included from drivers/hwmon/pmbus/ucd9000.c:19:0: ./include/linux/gpio/driver.h:576:1: error: redefinition of gpiochip_add_pin_range gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, ^~~~~~~~~~~~~~~~~~~~~~ In file included from drivers/hwmon/pmbus/ucd9000.c:18:0: ./include/linux/gpio.h:245:1: note: previous definition of gpiochip_add_pin_range was here gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, ^~~~~~~~~~~~~~~~~~~~~~ Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 964cb341882f ("gpio: move pincontrol calls to <linux/gpio/driver.h>") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Link: https://lore.kernel.org/r/20190731123814.46624-1-yuehaibing@huawei.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* NFS: Pass error information to the pgio error cleanup routineTrond Myklebust2019-09-061-1/+1
| | | | | | | | | | | [ Upstream commit df3accb849607a86278a37c35e6b313635ccc48b ] Allow the caller to pass error information when cleaning up a failed I/O request so that we can conditionally take action to cancel the request altogether if the error turned out to be fatal. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* NFS: Clean up list moves of struct nfs_pageTrond Myklebust2019-09-061-0/+10
| | | | | | | | | | | [ Upstream commit 078b5fd92c4913dd367361db6c28568386077c89 ] In several places we're just moving the struct nfs_page from one list to another by first removing from the existing list, then adding to the new one. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* lib: logic_pio: Add logic_pio_unregister_range()John Garry2019-09-061-0/+1
| | | | | | | | | | | | | | | | | commit b884e2de2afc68ce30f7093747378ef972dde253 upstream. Add a function to unregister a logical PIO range. Logical PIO space can still be leaked when unregistering certain LOGIC_PIO_CPU_MMIO regions, but this acceptable for now since there are no callers to unregister LOGIC_PIO_CPU_MMIO regions, and the logical PIO region allocation scheme would need significant work to improve this. Cc: stable@vger.kernel.org Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: Fix leak vCPU's VMCS value into other pCPUWanpeng Li2019-08-161-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 17e433b54393a6269acbcb792da97791fe1592d8 upstream. After commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts), a five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting in the VMs after stress testing: INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073) Call Trace: flush_tlb_mm_range+0x68/0x140 tlb_flush_mmu.part.75+0x37/0xe0 tlb_finish_mmu+0x55/0x60 zap_page_range+0x142/0x190 SyS_madvise+0x3cd/0x9c0 system_call_fastpath+0x1c/0x21 swait_active() sustains to be true before finish_swait() is called in kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop greatly increases the probability condition kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv is enabled the yield-candidate vCPU's VMCS RVI field leaks(by vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current VMCS. This patch fixes it by checking conservatively a subset of events. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Marc Zyngier <Marc.Zyngier@arm.com> Cc: stable@vger.kernel.org Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop) Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* crypto: ccp - Add support for valid authsize values less than 16Gary R Hook2019-08-161-0/+2
| | | | | | | | | | | | | | | commit 9f00baf74e4b6f79a3a3dfab44fb7bb2e797b551 upstream. AES GCM encryption allows for authsize values of 4, 8, and 12-16 bytes. Validate the requested authsize, and retain it to save in the request context. Fixes: 36cf515b9bbe2 ("crypto: ccp - Enable support for AES GCM on v5 CCPs") Cc: <stable@vger.kernel.org> Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cgroup: Include dying leaders with live threads in PROCS iterationsTejun Heo2019-08-092-0/+2
| | | | | | | | | | | | | | | | | | commit c03cd7738a83b13739f00546166969342c8ff014 upstream. CSS_TASK_ITER_PROCS currently iterates live group leaders; however, this means that a process with dying leader and live threads will be skipped. IOW, cgroup.procs might be empty while cgroup.threads isn't, which is confusing to say the least. Fix it by making cset track dying tasks and include dying leaders with live threads in PROCS iteration. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Topi Miettinen <toiwoton@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cgroup: Implement css_task_iter_skip()Tejun Heo2019-08-091-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | commit b636fd38dc40113f853337a7d2a6885ad23b8811 upstream. When a task is moved out of a cset, task iterators pointing to the task are advanced using the normal css_task_iter_advance() call. This is fine but we'll be tracking dying tasks on csets and thus moving tasks from cset->tasks to (to be added) cset->dying_tasks. When we remove a task from cset->tasks, if we advance the iterators, they may move over to the next cset before we had the chance to add the task back on the dying list, which can allow the task to escape iteration. This patch separates out skipping from advancing. Skipping only moves the affected iterators to the next pointer rather than fully advancing it and the following advancing will recognize that the cursor has already been moved forward and do the rest of advancing. This ensures that when a task moves from one list to another in its cset, as long as it moves in the right direction, it's always visible to iteration. This doesn't cause any visible behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* compat_ioctl: pppoe: fix PPPOEIOCSFWD handlingArnd Bergmann2019-08-091-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 055d88242a6046a1ceac3167290f054c72571cd9 ] Support for handling the PPPOEIOCSFWD ioctl in compat mode was added in linux-2.5.69 along with hundreds of other commands, but was always broken sincen only the structure is compatible, but the command number is not, due to the size being sizeof(size_t), or at first sizeof(sizeof((struct sockaddr_pppox)), which is different on 64-bit architectures. Guillaume Nault adds: And the implementation was broken until 2016 (see 29e73269aa4d ("pppoe: fix reference counting in PPPoE proxy")), and nobody ever noticed. I should probably have removed this ioctl entirely instead of fixing it. Clearly, it has never been used. Fix it by adding a compat_ioctl handler for all pppoe variants that translates the command number and then calls the regular ioctl function. All other ioctl commands handled by pppoe are compatible between 32-bit and 64-bit, and require compat_ptr() conversion. This should apply to all stable kernels. Acked-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net/mlx5e: Prevent encap flow counter update async to user queryAriel Levkovich2019-08-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 90bb769291161cf25a818d69cf608c181654473e ] This patch prevents a race between user invoked cached counters query and a neighbor last usage updater. The cached flow counter stats can be queried by calling "mlx5_fc_query_cached" which provides the number of bytes and packets that passed via this flow since the last time this counter was queried. It does so by reducting the last saved stats from the current, cached stats and then updating the last saved stats with the cached stats. It also provide the lastuse value for that flow. Since "mlx5e_tc_update_neigh_used_value" needs to retrieve the last usage time of encapsulation flows, it calls the flow counter query method periodically and async to user queries of the flow counter using cls_flower. This call is causing the driver to update the last reported bytes and packets from the cache and therefore, future user queries of the flow stats will return lower than expected number for bytes and packets since the last saved stats in the driver was updated async to the last saved stats in cls_flower. This causes wrong stats presentation of encapsulation flows to user. Since the neighbor usage updater only needs the lastuse stats from the cached counter, the fix is to use a dedicated lastuse query call that returns the lastuse value without synching between the cached stats and the last saved stats. Fixes: f6dfb4c3f216 ("net/mlx5e: Update neighbour 'used' state using HW flow rules counters") Signed-off-by: Ariel Levkovich <lariel@mellanox.com> Reviewed-by: Roi Dayan <roid@mellanox.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net/mlx5: Fix modify_cq_in alignmentEdward Srouji2019-08-091-1/+6
| | | | | | | | | | | | | | | [ Upstream commit 7a32f2962c56d9d8a836b4469855caeee8766bd4 ] Fix modify_cq_in alignment to match the device specification. After this fix the 'cq_umem_valid' field will be in the right offset. Cc: <stable@vger.kernel.org> # 4.19 Fixes: bd37197554eb ("net/mlx5: Update mlx5_ifc with DEVX UID bits") Signed-off-by: Edward Srouji <edwards@mellanox.com> Reviewed-by: Yishai Hadas <yishaih@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers/base: Introduce kill_device()Dan Williams2019-08-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 00289cd87676e14913d2d8492d1ce05c4baafdae upstream. The libnvdimm subsystem arranges for devices to be destroyed as a result of a sysfs operation. Since device_unregister() cannot be called from an actively running sysfs attribute of the same device libnvdimm arranges for device_unregister() to be performed in an out-of-line async context. The driver core maintains a 'dead' state for coordinating its own racing async registration / de-registration requests. Rather than add local 'dead' state tracking infrastructure to libnvdimm device objects, export the existing state tracking via a new kill_device() helper. The kill_device() helper simply marks the device as dead, i.e. that it is on its way to device_del(), or returns that the device was already dead. This can be used in advance of calling device_unregister() for subsystems like libnvdimm that might need to handle multiple user threads racing to delete a device. This refactoring does not change any behavior, but it is a pre-requisite for follow-on fixes and therefore marked for -stable. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Fixes: 4d88a97aa9e8 ("libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver...") Cc: <stable@vger.kernel.org> Tested-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/156341207332.292348.14959761496009347574.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* uapi linux/coda_psdev.h: move upc_req definition from uapi to kernel side ↵Mikko Rapeli2019-08-061-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | headers [ Upstream commit f90fb3c7e2c13ae829db2274b88b845a75038b8a ] Only users of upc_req in kernel side fs/coda/psdev.c and fs/coda/upcall.c already include linux/coda_psdev.h. Suggested by Jan Harkes <jaharkes@cs.cmu.edu> in https://lore.kernel.org/lkml/20150531111913.GA23377@cs.cmu.edu/ Fixes these include/uapi/linux/coda_psdev.h compilation errors in userspace: linux/coda_psdev.h:12:19: error: field `uc_chain' has incomplete type struct list_head uc_chain; ^ linux/coda_psdev.h:13:2: error: unknown type name `caddr_t' caddr_t uc_data; ^ linux/coda_psdev.h:14:2: error: unknown type name `u_short' u_short uc_flags; ^ linux/coda_psdev.h:15:2: error: unknown type name `u_short' u_short uc_inSize; /* Size is at most 5000 bytes */ ^ linux/coda_psdev.h:16:2: error: unknown type name `u_short' u_short uc_outSize; ^ linux/coda_psdev.h:17:2: error: unknown type name `u_short' u_short uc_opcode; /* copied from data to save lookup */ ^ linux/coda_psdev.h:19:2: error: unknown type name `wait_queue_head_t' wait_queue_head_t uc_sleep; /* process' wait queue */ ^ Link: http://lkml.kernel.org/r/9f99f5ce6a0563d5266e6cf7aa9585aac2cae971.1558117389.git.jaharkes@cs.cmu.edu Signed-off-by: Mikko Rapeli <mikko.rapeli@iki.fi> Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Colin Ian King <colin.king@canonical.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Howells <dhowells@redhat.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Sam Protsenko <semen.protsenko@linaro.org> Cc: Yann Droneaud <ydroneaud@opteya.com> Cc: Zhouyang Jia <jiazhouyang09@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* coda: fix build using bare-metal toolchainSam Protsenko2019-08-061-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit b2a57e334086602be56b74958d9f29b955cd157f ] The kernel is self-contained project and can be built with bare-metal toolchain. But bare-metal toolchain doesn't define __linux__. Because of this u_quad_t type is not defined when using bare-metal toolchain and codafs build fails. This patch fixes it by defining u_quad_t type unconditionally. Link: http://lkml.kernel.org/r/3cbb40b0a57b6f9923a9d67b53473c0b691a3eaa.1558117389.git.jaharkes@cs.cmu.edu Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org> Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Colin Ian King <colin.king@canonical.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Howells <dhowells@redhat.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Mikko Rapeli <mikko.rapeli@iki.fi> Cc: Yann Droneaud <ydroneaud@opteya.com> Cc: Zhouyang Jia <jiazhouyang09@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ACPI: fix false-positive -Wuninitialized warningArnd Bergmann2019-08-061-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit dfd6f9ad36368b8dbd5f5a2b2f0a4705ae69a323 ] clang gets confused by an uninitialized variable in what looks to it like a never executed code path: arch/x86/kernel/acpi/boot.c:618:13: error: variable 'polarity' is uninitialized when used here [-Werror,-Wuninitialized] polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; ^~~~~~~~ arch/x86/kernel/acpi/boot.c:606:32: note: initialize the variable 'polarity' to silence this warning int rc, irq, trigger, polarity; ^ = 0 arch/x86/kernel/acpi/boot.c:617:12: error: variable 'trigger' is uninitialized when used here [-Werror,-Wuninitialized] trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; ^~~~~~~ arch/x86/kernel/acpi/boot.c:606:22: note: initialize the variable 'trigger' to silence this warning int rc, irq, trigger, polarity; ^ = 0 This is unfortunately a design decision in clang and won't be fixed. Changing the acpi_get_override_irq() macro to an inline function reliably avoids the issue. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* block, scsi: Change the preempt-only flag into a counterBart Van Assche2019-08-041-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit cd84a62e0078dce09f4ed349bec84f86c9d54b30 upstream. The RQF_PREEMPT flag is used for three purposes: - In the SCSI core, for making sure that power management requests are executed even if a device is in the "quiesced" state. - For domain validation by SCSI drivers that use the parallel port. - In the IDE driver, for IDE preempt requests. Rename "preempt-only" into "pm-only" because the primary purpose of this mode is power management. Since the power management core may but does not have to resume a runtime suspended device before performing system-wide suspend and since a later patch will set "pm-only" mode as long as a block device is runtime suspended, make it possible to set "pm-only" mode from more than one context. Since with this change scsi_device_quiesce() is no longer idempotent, make that function return early if it is called for a quiesced queue. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Jianchao Wang <jianchao.w.wang@oracle.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sched/fair: Use RCU accessors consistently for ->numa_groupJann Horn2019-08-041-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | commit cb361d8cdef69990f6b4504dc1fd9a594d983c97 upstream. The old code used RCU annotations and accessors inconsistently for ->numa_group, which can lead to use-after-frees and NULL dereferences. Let all accesses to ->numa_group use proper RCU helpers to prevent such issues. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Fixes: 8c8a743c5087 ("sched/numa: Use {cpu, pid} to create task groups for shared faults") Link: https://lkml.kernel.org/r/20190716152047.14424-3-jannh@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sched/fair: Don't free p->numa_faults with concurrent readersJann Horn2019-08-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 16d51a590a8ce3befb1308e0e7ab77f3b661af33 upstream. When going through execve(), zero out the NUMA fault statistics instead of freeing them. During execve, the task is reachable through procfs and the scheduler. A concurrent /proc/*/sched reader can read data from a freed ->numa_faults allocation (confirmed by KASAN) and write it back to userspace. I believe that it would also be possible for a use-after-free read to occur through a race between a NUMA fault and execve(): task_numa_fault() can lead to task_numa_compare(), which invokes task_weight() on the currently running task of a different CPU. Another way to fix this would be to make ->numa_faults RCU-managed or add extra locking, but it seems easier to wipe the NUMA fault statistics on execve. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Fixes: 82727018b0d3 ("sched/numa: Call task_numa_free() from do_execve()") Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/iova: Fix compilation error with !CONFIG_IOMMU_IOVAJoerg Roedel2019-08-041-1/+1
| | | | | | | | | | | | | commit 201c1db90cd643282185a00770f12f95da330eca upstream. The stub function for !CONFIG_IOMMU_IOVA needs to be 'static inline'. Fixes: effa467870c76 ('iommu/vt-d: Don't queue_iova() if there is no flush queue') Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/vt-d: Don't queue_iova() if there is no flush queueDmitry Safonov2019-08-041-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit effa467870c7612012885df4e246bdb8ffd8e44c upstream. Intel VT-d driver was reworked to use common deferred flushing implementation. Previously there was one global per-cpu flush queue, afterwards - one per domain. Before deferring a flush, the queue should be allocated and initialized. Currently only domains with IOMMU_DOMAIN_DMA type initialize their flush queue. It's probably worth to init it for static or unmanaged domains too, but it may be arguable - I'm leaving it to iommu folks. Prevent queuing an iova flush if the domain doesn't have a queue. The defensive check seems to be worth to keep even if queue would be initialized for all kinds of domains. And is easy backportable. On 4.19.43 stable kernel it has a user-visible effect: previously for devices in si domain there were crashes, on sata devices: BUG: spinlock bad magic on CPU#6, swapper/0/1 lock: 0xffff88844f582008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #1 Call Trace: <IRQ> dump_stack+0x61/0x7e spin_bug+0x9d/0xa3 do_raw_spin_lock+0x22/0x8e _raw_spin_lock_irqsave+0x32/0x3a queue_iova+0x45/0x115 intel_unmap+0x107/0x113 intel_unmap_sg+0x6b/0x76 __ata_qc_complete+0x7f/0x103 ata_qc_complete+0x9b/0x26a ata_qc_complete_multiple+0xd0/0xe3 ahci_handle_port_interrupt+0x3ee/0x48a ahci_handle_port_intr+0x73/0xa9 ahci_single_level_irq_intr+0x40/0x60 __handle_irq_event_percpu+0x7f/0x19a handle_irq_event_percpu+0x32/0x72 handle_irq_event+0x38/0x56 handle_edge_irq+0x102/0x121 handle_irq+0x147/0x15c do_IRQ+0x66/0xf2 common_interrupt+0xf/0xf RIP: 0010:__do_softirq+0x8c/0x2df The same for usb devices that use ehci-pci: BUG: spinlock bad magic on CPU#0, swapper/0/1 lock: 0xffff88844f402008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #4 Call Trace: <IRQ> dump_stack+0x61/0x7e spin_bug+0x9d/0xa3 do_raw_spin_lock+0x22/0x8e _raw_spin_lock_irqsave+0x32/0x3a queue_iova+0x77/0x145 intel_unmap+0x107/0x113 intel_unmap_page+0xe/0x10 usb_hcd_unmap_urb_setup_for_dma+0x53/0x9d usb_hcd_unmap_urb_for_dma+0x17/0x100 unmap_urb_for_dma+0x22/0x24 __usb_hcd_giveback_urb+0x51/0xc3 usb_giveback_urb_bh+0x97/0xde tasklet_action_common.isra.4+0x5f/0xa1 tasklet_action+0x2d/0x30 __do_softirq+0x138/0x2df irq_exit+0x7d/0x8b smp_apic_timer_interrupt+0x10f/0x151 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0010:_raw_spin_unlock_irqrestore+0x17/0x39 Cc: David Woodhouse <dwmw2@infradead.org> Cc: Joerg Roedel <joro@8bytes.org> Cc: Lu Baolu <baolu.lu@linux.intel.com> Cc: iommu@lists.linux-foundation.org Cc: <stable@vger.kernel.org> # 4.14+ Fixes: 13cf01744608 ("iommu/vt-d: Make use of iova deferred flushing") Signed-off-by: Dmitry Safonov <dima@arista.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> [v4.14-port notes: o minor conflict with untrusted IOMMU devices check under if-condition] Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* access: avoid the RCU grace period for the temporary subjective credentialsLinus Torvalds2019-07-311-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d7852fbd0f0423937fa287a598bfde188bb68c22 upstream. It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU work because it installs a temporary credential that gets allocated and freed for each system call. The allocation and freeing overhead is mostly benign, but because credentials can be accessed under the RCU read lock, the freeing involves a RCU grace period. Which is not a huge deal normally, but if you have a lot of access() calls, this causes a fair amount of seconday damage: instead of having a nice alloc/free patterns that hits in hot per-CPU slab caches, you have all those delayed free's, and on big machines with hundreds of cores, the RCU overhead can end up being enormous. But it turns out that all of this is entirely unnecessary. Exactly because access() only installs the credential as the thread-local subjective credential, the temporary cred pointer doesn't actually need to be RCU free'd at all. Once we're done using it, we can just free it synchronously and avoid all the RCU overhead. So add a 'non_rcu' flag to 'struct cred', which can be set by users that know they only use it in non-RCU context (there are other potential users for this). We can make it a union with the rcu freeing list head that we need for the RCU case, so this doesn't need any extra storage. Note that this also makes 'get_current_cred()' clear the new non_rcu flag, in case we have filesystems that take a long-term reference to the cred and then expect the RCU delayed freeing afterwards. It's not entirely clear that this is required, but it makes for clear semantics: the subjective cred remains non-RCU as long as you only access it synchronously using the thread-local accessors, but you _can_ use it as a generic cred if you want to. It is possible that we should just remove the whole RCU markings for ->cred entirely. Only ->real_cred is really supposed to be accessed through RCU, and the long-term cred copies that nfs uses might want to explicitly re-enable RCU freeing if required, rather than have get_current_cred() do it implicitly. But this is a "minimal semantic changes" change for the immediate problem. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jan Glauber <jglauber@marvell.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Jayachandran Chandrasekharan Nair <jnair@marvell.com> Cc: Greg KH <greg@kroah.com> Cc: Kees Cook <keescook@chromium.org> Cc: David Howells <dhowells@redhat.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpu: host1x: Increase maximum DMA segment sizeThierry Reding2019-07-311-0/+2
| | | | | | | | | | | | | | | | | | | [ Upstream commit 1e390478cfb527e34c9ab89ba57212cb05c33c51 ] Recent versions of the DMA API debug code have started to warn about violations of the maximum DMA segment size. This is because the segment size defaults to 64 KiB, which can easily be exceeded in large buffer allocations such as used in DRM/KMS for framebuffers. Technically the Tegra SMMU and ARM SMMU don't have a maximum segment size (they map individual pages irrespective of whether they are contiguous or not), so the choice of 4 MiB is a bit arbitrary here. The maximum segment size is a 32-bit unsigned integer, though, so we can't set it to the correct maximum size, which would be the size of the aperture. Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* jbd2: introduce jbd2_inode dirty range scopingRoss Zwisler2019-07-281-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6ba0e7dc64a5adcda2fbe65adc466891795d639e upstream. Currently both journal_submit_inode_data_buffers() and journal_finish_inode_data_buffers() operate on the entire address space of each of the inodes associated with a given journal entry. The consequence of this is that if we have an inode where we are constantly appending dirty pages we can end up waiting for an indefinite amount of time in journal_finish_inode_data_buffers() while we wait for all the pages under writeback to be written out. The easiest way to cause this type of workload is do just dd from /dev/zero to a file until it fills the entire filesystem. This can cause journal_finish_inode_data_buffers() to wait for the duration of the entire dd operation. We can improve this situation by scoping each of the inode dirty ranges associated with a given transaction. We do this via the jbd2_inode structure so that the scoping is contained within jbd2 and so that it follows the lifetime and locking rules for that structure. This allows us to limit the writeback & wait in journal_submit_inode_data_buffers() and journal_finish_inode_data_buffers() respectively to the dirty range for a given struct jdb2_inode, keeping us from waiting forever if the inode in question is still being appended to. Signed-off-by: Ross Zwisler <zwisler@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: add filemap_fdatawait_range_keep_errors()Ross Zwisler2019-07-281-0/+2
| | | | | | | | | | | | | | | | commit aa0bfcd939c30617385ffa28682c062d78050eba upstream. In the spirit of filemap_fdatawait_range() and filemap_fdatawait_keep_errors(), introduce filemap_fdatawait_range_keep_errors() which both takes a range upon which to wait and does not clear errors from the address space. Signed-off-by: Ross Zwisler <zwisler@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf/core: Fix exclusive events' groupingAlexander Shishkin2019-07-281-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8a58ddae23796c733c5dfbd717538d89d036c5bd upstream. So far, we tried to disallow grouping exclusive events for the fear of complications they would cause with moving between contexts. Specifically, moving a software group to a hardware context would violate the exclusivity rules if both groups contain matching exclusive events. This attempt was, however, unsuccessful: the check that we have in the perf_event_open() syscall is both wrong (looks at wrong PMU) and insufficient (group leader may still be exclusive), as can be illustrated by running: $ perf record -e '{intel_pt//,cycles}' uname $ perf record -e '{cycles,intel_pt//}' uname ultimately successfully. Furthermore, we are completely free to trigger the exclusivity violation by: perf -e '{cycles,intel_pt//}' -e '{intel_pt//,instructions}' even though the helpful perf record will not allow that, the ABI will. The warning later in the perf_event_open() path will also not trigger, because it's also wrong. Fix all this by validating the original group before moving, getting rid of broken safeguards and placing a useful one to perf_install_in_context(). Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.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: mathieu.poirier@linaro.org Cc: will.deacon@arm.com Fixes: bed5b25ad9c8a ("perf: Add a pmu capability for "exclusive" events") Link: https://lkml.kernel.org/r/20190701110755.24646-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* clocksource/drivers/exynos_mct: Increase priority over ARM arch timerMarek Szyprowski2019-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 6282edb72bed5324352522d732080d4c1b9dfed6 ] Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT (Multi Core Timer) and standard ARM Architected Timers. There are use cases, where both timer interfaces are used simultanously. One of such examples is using Exynos MCT for the main system timer and ARM Architected Timers for the KVM and virtualized guests (KVM requires arch timers). Exynos Multi-Core Timer driver (exynos_mct) must be however started before ARM Architected Timers (arch_timer), because they both share some common hardware blocks (global system counter) and turning on MCT is needed to get ARM Architected Timer working properly. To ensure selecting Exynos MCT as the main system timer, increase MCT timer rating. To ensure proper starting order of both timers during suspend/resume cycle, increase MCT hotplug priority over ARM Archictected Timers. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* rcu: Force inlining of rcu_read_lock()Waiman Long2019-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 6da9f775175e516fc7229ceaa9b54f8f56aa7924 ] When debugging options are turned on, the rcu_read_lock() function might not be inlined. This results in lockdep's print_lock() function printing "rcu_read_lock+0x0/0x70" instead of rcu_read_lock()'s caller. For example: [ 10.579995] ============================= [ 10.584033] WARNING: suspicious RCU usage [ 10.588074] 4.18.0.memcg_v2+ #1 Not tainted [ 10.593162] ----------------------------- [ 10.597203] include/linux/rcupdate.h:281 Illegal context switch in RCU read-side critical section! [ 10.606220] [ 10.606220] other info that might help us debug this: [ 10.606220] [ 10.614280] [ 10.614280] rcu_scheduler_active = 2, debug_locks = 1 [ 10.620853] 3 locks held by systemd/1: [ 10.624632] #0: (____ptrval____) (&type->i_mutex_dir_key#5){.+.+}, at: lookup_slow+0x42/0x70 [ 10.633232] #1: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70 [ 10.640954] #2: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70 These "rcu_read_lock+0x0/0x70" strings are not providing any useful information. This commit therefore forces inlining of the rcu_read_lock() function so that rcu_read_lock()'s caller is instead shown. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* linux/kernel.h: fix overflow for DIV_ROUND_UP_ULLVinod Koul2019-07-211-1/+2
| | | | | | | | | | | | | | | | | | | | [ Upstream commit 8f9fab480c7a87b10bb5440b5555f370272a5d59 ] DIV_ROUND_UP_ULL adds the two arguments and then invokes DIV_ROUND_DOWN_ULL. But on a 32bit system the addition of two 32 bit values can overflow. DIV_ROUND_DOWN_ULL does it correctly and stashes the addition into a unsigned long long so cast the result to unsigned long long here to avoid the overflow condition. [akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval] Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org Signed-off-by: Vinod Koul <vkoul@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDTJames Morse2019-07-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream. The cacheinfo structures are alloced/freed by cpu online/offline callbacks. Originally these were only used by sysfs to expose the cache topology to user space. Without any in-kernel dependencies CPUHP_AP_ONLINE_DYN was an appropriate choice. resctrl has started using these structures to identify CPUs that share a cache. It updates its 'domain' structures from cpu online/offline callbacks. These depend on the cacheinfo structures (resctrl_online_cpu()->domain_add_cpu()->get_cache_id()-> get_cpu_cacheinfo()). These also run as CPUHP_AP_ONLINE_DYN. Now that there is an in-kernel dependency, move the cacheinfo work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN work runs. Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology") Cc: <stable@vger.kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: James Morse <james.morse@arm.com> Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* VMCI: Fix integer overflow in VMCI handle arraysVishnu DASA2019-07-141-1/+10
| | | | | | | | | | | | | | | | | | | | commit 1c2eb5b2853c9f513690ba6b71072d8eb65da16a upstream. The VMCI handle array has an integer overflow in vmci_handle_arr_append_entry when it tries to expand the array. This can be triggered from a guest, since the doorbell link hypercall doesn't impose a limit on the number of doorbell handles that a VM can create in the hypervisor, and these handles are stored in a handle array. In this change, we introduce a mandatory max capacity for handle arrays/lists to avoid excessive memory usage. Signed-off-by: Vishnu Dasa <vdasa@vmware.com> Reviewed-by: Adit Ranadive <aditr@vmware.com> Reviewed-by: Jorgen Hansen <jhansen@vmware.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64KDaniel Borkmann2019-07-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit fdadd04931c2d7cd294dc5b2b342863f94be53a3 ] Michael and Sandipan report: Commit ede95a63b5 introduced a bpf_jit_limit tuneable to limit BPF JIT allocations. At compile time it defaults to PAGE_SIZE * 40000, and is adjusted again at init time if MODULES_VADDR is defined. For ppc64 kernels, MODULES_VADDR isn't defined, so we're stuck with the compile-time default at boot-time, which is 0x9c400000 when using 64K page size. This overflows the signed 32-bit bpf_jit_limit value: root@ubuntu:/tmp# cat /proc/sys/net/core/bpf_jit_limit -1673527296 and can cause various unexpected failures throughout the network stack. In one case `strace dhclient eth0` reported: setsockopt(5, SOL_SOCKET, SO_ATTACH_FILTER, {len=11, filter=0x105dd27f8}, 16) = -1 ENOTSUPP (Unknown error 524) and similar failures can be seen with tools like tcpdump. This doesn't always reproduce however, and I'm not sure why. The more consistent failure I've seen is an Ubuntu 18.04 KVM guest booted on a POWER9 host would time out on systemd/netplan configuring a virtio-net NIC with no noticeable errors in the logs. Given this and also given that in near future some architectures like arm64 will have a custom area for BPF JIT image allocations we should get rid of the BPF_JIT_LIMIT_DEFAULT fallback / default entirely. For 4.21, we have an overridable bpf_jit_alloc_exec(), bpf_jit_free_exec() so therefore add another overridable bpf_jit_alloc_exec_limit() helper function which returns the possible size of the memory area for deriving the default heuristic in bpf_jit_charge_init(). Like bpf_jit_alloc_exec() and bpf_jit_free_exec(), the new bpf_jit_alloc_exec_limit() assumes that module_alloc() is the default JIT memory provider, and therefore in case archs implement their custom module_alloc() we use MODULES_{END,_VADDR} for limits and otherwise for vmalloc_exec() cases like on ppc64 we use VMALLOC_{END,_START}. Additionally, for archs supporting large page sizes, we should change the sysctl to be handled as long to not run into sysctl restrictions in future. Fixes: ede95a63b5e8 ("bpf: add bpf_jit_limit knob to restrict unpriv allocations") Reported-by: Sandipan Das <sandipan@linux.ibm.com> Reported-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* bpf: fix unconnected udp hooksDaniel Borkmann2019-07-031-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 983695fa676568fc0fe5ddd995c7267aabc24632 upstream. Intention of cgroup bind/connect/sendmsg BPF hooks is to act transparently to applications as also stated in original motivation in 7828f20e3779 ("Merge branch 'bpf-cgroup-bind-connect'"). When recently integrating the latter two hooks into Cilium to enable host based load-balancing with Kubernetes, I ran into the issue that pods couldn't start up as DNS got broken. Kubernetes typically sets up DNS as a service and is thus subject to load-balancing. Upon further debugging, it turns out that the cgroupv2 sendmsg BPF hooks API is currently insufficient and thus not usable as-is for standard applications shipped with most distros. To break down the issue we ran into with a simple example: # cat /etc/resolv.conf nameserver 147.75.207.207 nameserver 147.75.207.208 For the purpose of a simple test, we set up above IPs as service IPs and transparently redirect traffic to a different DNS backend server for that node: # cilium service list ID Frontend Backend 1 147.75.207.207:53 1 => 8.8.8.8:53 2 147.75.207.208:53 1 => 8.8.8.8:53 The attached BPF program is basically selecting one of the backends if the service IP/port matches on the cgroup hook. DNS breaks here, because the hooks are not transparent enough to applications which have built-in msg_name address checks: # nslookup 1.1.1.1 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 [...] ;; connection timed out; no servers could be reached # dig 1.1.1.1 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 [...] ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1 ;; global options: +cmd ;; connection timed out; no servers could be reached For comparison, if none of the service IPs is used, and we tell nslookup to use 8.8.8.8 directly it works just fine, of course: # nslookup 1.1.1.1 8.8.8.8 1.1.1.1.in-addr.arpa name = one.one.one.one. In order to fix this and thus act more transparent to the application, this needs reverse translation on recvmsg() side. A minimal fix for this API is to add similar recvmsg() hooks behind the BPF cgroups static key such that the program can track state and replace the current sockaddr_in{,6} with the original service IP. From BPF side, this basically tracks the service tuple plus socket cookie in an LRU map where the reverse NAT can then be retrieved via map value as one example. Side-note: the BPF cgroups static key should be converted to a per-hook static key in future. Same example after this fix: # cilium service list ID Frontend Backend 1 147.75.207.207:53 1 => 8.8.8.8:53 2 147.75.207.208:53 1 => 8.8.8.8:53 Lookups work fine now: # nslookup 1.1.1.1 1.1.1.1.in-addr.arpa name = one.one.one.one. Authoritative answers can be found from: # dig 1.1.1.1 ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 51550 ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;1.1.1.1. IN A ;; AUTHORITY SECTION: . 23426 IN SOA a.root-servers.net. nstld.verisign-grs.com. 2019052001 1800 900 604800 86400 ;; Query time: 17 msec ;; SERVER: 147.75.207.207#53(147.75.207.207) ;; WHEN: Tue May 21 12:59:38 UTC 2019 ;; MSG SIZE rcvd: 111 And from an actual packet level it shows that we're using the back end server when talking via 147.75.207.20{7,8} front end: # tcpdump -i any udp [...] 12:59:52.698732 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38) 12:59:52.698735 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38) 12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67) 12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67) [...] In order to be flexible and to have same semantics as in sendmsg BPF programs, we only allow return codes in [1,1] range. In the sendmsg case the program is called if msg->msg_name is present which can be the case in both, connected and unconnected UDP. The former only relies on the sockaddr_in{,6} passed via connect(2) if passed msg->msg_name was NULL. Therefore, on recvmsg side, we act in similar way to call into the BPF program whenever a non-NULL msg->msg_name was passed independent of sk->sk_state being TCP_ESTABLISHED or not. Note that for TCP case, the msg->msg_name is ignored in the regular recvmsg path and therefore not relevant. For the case of ip{,v6}_recv_error() paths, picked up via MSG_ERRQUEUE, the hook is not called. This is intentional as it aligns with the same semantics as in case of TCP cgroup BPF hooks right now. This might be better addressed in future through a different bpf_attach_type such that this case can be distinguished from the regular recvmsg paths, for example. Fixes: 1cedee13d25a ("bpf: Hooks for sys_sendmsg") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrey Ignatov <rdna@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Martynas Pumputis <m@lambda.lt> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* SUNRPC: Clean up initialisation of the struct rpc_rqstTrond Myklebust2019-07-031-1/+0
| | | | | | | | | | | | commit 9dc6edcf676fe188430e8b119f91280bbf285163 upstream. Move the initialisation back into xprt.c. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Yihao Wu <wuyihao@linux.alibaba.com> Cc: Caspar Zhang <caspar@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mmc: core: Add sdio_retune_hold_now() and sdio_retune_release()Douglas Anderson2019-06-251-0/+3
| | | | | | | | | | | | | | | | | commit b4c9f938d542d5f88c501744d2d12fad4fd2915f upstream. We want SDIO drivers to be able to temporarily stop retuning when the driver knows that the SDIO card is not in a state where retuning will work (maybe because the card is asleep). We'll move the relevant functions to a place where drivers can call them. Cc: stable@vger.kernel.org #v4.18+ Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mmc: core: API to temporarily disable retuning for SDIO CRC errorsDouglas Anderson2019-06-252-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 0a55f4ab9678413a01e740c86e9367ba0c612b36 upstream. Normally when the MMC core sees an "-EILSEQ" error returned by a host controller then it will trigger a retuning of the card. This is generally a good idea. However, if a command is expected to sometimes cause transfer errors then these transfer errors shouldn't cause a re-tuning. This re-tuning will be a needless waste of time. One example case where a transfer is expected to cause errors is when transitioning between idle (sometimes referred to as "sleep" in Broadcom code) and active state on certain Broadcom WiFi SDIO cards. Specifically if the card was already transitioning between states when the command was sent it could cause an error on the SDIO bus. Let's add an API that the SDIO function drivers can call that will temporarily disable the auto-tuning functionality. Then we can add a call to this in the Broadcom WiFi driver and any other driver that might have similar needs. NOTE: this makes the assumption that the card is already tuned well enough that it's OK to disable the auto-retuning during one of these error-prone situations. Presumably the driver code performing the error-prone transfer knows how to recover / retry from errors. ...and after we can get back to a state where transfers are no longer error-prone then we can enable the auto-retuning again. If we truly find ourselves in a case where the card needs to be retuned sometimes to handle one of these error-prone transfers then we can always try a few transfers first without auto-retuning and then re-try with auto-retuning if the first few fail. Without this change on rk3288-veyron-minnie I periodically see this in the logs of a machine just sitting there idle: dwmmc_rockchip ff0d0000.dwmmc: Successfully tuned phase to XYZ Cc: stable@vger.kernel.org #v4.18+ Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* coredump: fix race condition between collapse_huge_page() and core dumpingAndrea Arcangeli2019-06-221-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 59ea6d06cfa9247b586a695c21f94afa7183af74 upstream. When fixing the race conditions between the coredump and the mmap_sem holders outside the context of the process, we focused on mmget_not_zero()/get_task_mm() callers in 04f5866e41fb70 ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping"), but those aren't the only cases where the mmap_sem can be taken outside of the context of the process as Michal Hocko noticed while backporting that commit to older -stable kernels. If mmgrab() is called in the context of the process, but then the mm_count reference is transferred outside the context of the process, that can also be a problem if the mmap_sem has to be taken for writing through that mm_count reference. khugepaged registration calls mmgrab() in the context of the process, but the mmap_sem for writing is taken later in the context of the khugepaged kernel thread. collapse_huge_page() after taking the mmap_sem for writing doesn't modify any vma, so it's not obvious that it could cause a problem to the coredump, but it happens to modify the pmd in a way that breaks an invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page() needs the mmap_sem for writing just to block concurrent page faults that call pmd_trans_huge_lock(). Specifically the invariant that "!pmd_trans_huge()" cannot become a "pmd_trans_huge()" doesn't hold while collapse_huge_page() runs. The coredump will call __get_user_pages() without mmap_sem for reading, which eventually can invoke a lockless page fault which will need a functional pmd_trans_huge_lock(). So collapse_huge_page() needs to use mmget_still_valid() to check it's not running concurrently with the coredump... as long as the coredump can invoke page faults without holding the mmap_sem for reading. This has "Fixes: khugepaged" to facilitate backporting, but in my view it's more a bug in the coredump code that will eventually have to be rewritten to stop invoking page faults without the mmap_sem for reading. So the long term plan is still to drop all mmget_still_valid(). Link: http://lkml.kernel.org/r/20190607161558.32104-1-aarcange@redhat.com Fixes: ba76149f47d8 ("thp: khugepaged") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Peter Xu <peterx@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/microcode, cpuhotplug: Add a microcode loader CPU hotplug callbackBorislav Petkov2019-06-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 78f4e932f7760d965fb1569025d1576ab77557c5 upstream. Adric Blake reported the following warning during suspend-resume: Enabling non-boot CPUs ... x86: Booting SMP configuration: smpboot: Booting Node 0 Processor 1 APIC 0x2 unchecked MSR access error: WRMSR to 0x10f (tried to write 0x0000000000000000) \ at rIP: 0xffffffff8d267924 (native_write_msr+0x4/0x20) Call Trace: intel_set_tfa intel_pmu_cpu_starting ? x86_pmu_dead_cpu x86_pmu_starting_cpu cpuhp_invoke_callback ? _raw_spin_lock_irqsave notify_cpu_starting start_secondary secondary_startup_64 microcode: sig=0x806ea, pf=0x80, revision=0x96 microcode: updated to revision 0xb4, date = 2019-04-01 CPU1 is up The MSR in question is MSR_TFA_RTM_FORCE_ABORT and that MSR is emulated by microcode. The log above shows that the microcode loader callback happens after the PMU restoration, leading to the conjecture that because the microcode hasn't been updated yet, that MSR is not present yet, leading to the #GP. Add a microcode loader-specific hotplug vector which comes before the PERF vectors and thus executes earlier and makes sure the MSR is present. Fixes: 400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort") Reported-by: Adric Blake <promarbler14@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: x86@kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=203637 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cgroup: Use css_tryget() instead of css_tryget_online() in task_get_css()Tejun Heo2019-06-191-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 18fa84a2db0e15b02baa5d94bdb5bd509175d2f6 upstream. A PF_EXITING task can stay associated with an offline css. If such task calls task_get_css(), it can get stuck indefinitely. This can be triggered by BSD process accounting which writes to a file with PF_EXITING set when racing against memcg disable as in the backtrace at the end. After this change, task_get_css() may return a css which was already offline when the function was called. None of the existing users are affected by this change. INFO: rcu_sched self-detected stall on CPU INFO: rcu_sched detected stalls on CPUs/tasks: ... NMI backtrace for cpu 0 ... Call Trace: <IRQ> dump_stack+0x46/0x68 nmi_cpu_backtrace.cold.2+0x13/0x57 nmi_trigger_cpumask_backtrace+0xba/0xca rcu_dump_cpu_stacks+0x9e/0xce rcu_check_callbacks.cold.74+0x2af/0x433 update_process_times+0x28/0x60 tick_sched_timer+0x34/0x70 __hrtimer_run_queues+0xee/0x250 hrtimer_interrupt+0xf4/0x210 smp_apic_timer_interrupt+0x56/0x110 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0010:balance_dirty_pages_ratelimited+0x28f/0x3d0 ... btrfs_file_write_iter+0x31b/0x563 __vfs_write+0xfa/0x140 __kernel_write+0x4f/0x100 do_acct_process+0x495/0x580 acct_process+0xb9/0xdb do_exit+0x748/0xa00 do_group_exit+0x3a/0xa0 get_signal+0x254/0x560 do_signal+0x23/0x5c0 exit_to_usermode_loop+0x5d/0xa0 prepare_exit_to_usermode+0x53/0x80 retint_user+0x8/0x8 Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org # v4.2+ Fixes: ec438699a9ae ("cgroup, block: implement task_get_css() and use it in bio_associate_current()") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tcp: limit payload size of sacked skbsEric Dumazet2019-06-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff upstream. Jonathan Looney reported that TCP can trigger the following crash in tcp_shifted_skb() : BUG_ON(tcp_skb_pcount(skb) < pcount); This can happen if the remote peer has advertized the smallest MSS that linux TCP accepts : 48 An skb can hold 17 fragments, and each fragment can hold 32KB on x86, or 64KB on PowerPC. This means that the 16bit witdh of TCP_SKB_CB(skb)->tcp_gso_segs can overflow. Note that tcp_sendmsg() builds skbs with less than 64KB of payload, so this problem needs SACK to be enabled. SACK blocks allow TCP to coalesce multiple skbs in the retransmit queue, thus filling the 17 fragments to maximal capacity. CVE-2019-11477 -- u16 overflow of TCP_SKB_CB(skb)->tcp_gso_segs Fixes: 832d11c5cd07 ("tcp: Try to restore large SKBs while SACK processing") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* pwm: Fix deadlock warning when removing PWM devicePhong Hoang2019-06-151-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 347ab9480313737c0f1aaa08e8f2e1a791235535 ] This patch fixes deadlock warning if removing PWM device when CONFIG_PROVE_LOCKING is enabled. This issue can be reproceduced by the following steps on the R-Car H3 Salvator-X board if the backlight is disabled: # cd /sys/class/pwm/pwmchip0 # echo 0 > export # ls device export npwm power pwm0 subsystem uevent unexport # cd device/driver # ls bind e6e31000.pwm uevent unbind # echo e6e31000.pwm > unbind [ 87.659974] ====================================================== [ 87.666149] WARNING: possible circular locking dependency detected [ 87.672327] 5.0.0 #7 Not tainted [ 87.675549] ------------------------------------------------------ [ 87.681723] bash/2986 is trying to acquire lock: [ 87.686337] 000000005ea0e178 (kn->count#58){++++}, at: kernfs_remove_by_name_ns+0x50/0xa0 [ 87.694528] [ 87.694528] but task is already holding lock: [ 87.700353] 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.707405] [ 87.707405] which lock already depends on the new lock. [ 87.707405] [ 87.715574] [ 87.715574] the existing dependency chain (in reverse order) is: [ 87.723048] [ 87.723048] -> #1 (pwm_lock){+.+.}: [ 87.728017] __mutex_lock+0x70/0x7e4 [ 87.732108] mutex_lock_nested+0x1c/0x24 [ 87.736547] pwm_request_from_chip.part.6+0x34/0x74 [ 87.741940] pwm_request_from_chip+0x20/0x40 [ 87.746725] export_store+0x6c/0x1f4 [ 87.750820] dev_attr_store+0x18/0x28 [ 87.754998] sysfs_kf_write+0x54/0x64 [ 87.759175] kernfs_fop_write+0xe4/0x1e8 [ 87.763615] __vfs_write+0x40/0x184 [ 87.767619] vfs_write+0xa8/0x19c [ 87.771448] ksys_write+0x58/0xbc [ 87.775278] __arm64_sys_write+0x18/0x20 [ 87.779721] el0_svc_common+0xd0/0x124 [ 87.783986] el0_svc_compat_handler+0x1c/0x24 [ 87.788858] el0_svc_compat+0x8/0x18 [ 87.792947] [ 87.792947] -> #0 (kn->count#58){++++}: [ 87.798260] lock_acquire+0xc4/0x22c [ 87.802353] __kernfs_remove+0x258/0x2c4 [ 87.806790] kernfs_remove_by_name_ns+0x50/0xa0 [ 87.811836] remove_files.isra.1+0x38/0x78 [ 87.816447] sysfs_remove_group+0x48/0x98 [ 87.820971] sysfs_remove_groups+0x34/0x4c [ 87.825583] device_remove_attrs+0x6c/0x7c [ 87.830197] device_del+0x11c/0x33c [ 87.834201] device_unregister+0x14/0x2c [ 87.838638] pwmchip_sysfs_unexport+0x40/0x4c [ 87.843509] pwmchip_remove+0xf4/0x13c [ 87.847773] rcar_pwm_remove+0x28/0x34 [ 87.852039] platform_drv_remove+0x24/0x64 [ 87.856651] device_release_driver_internal+0x18c/0x21c [ 87.862391] device_release_driver+0x14/0x1c [ 87.867175] unbind_store+0xe0/0x124 [ 87.871265] drv_attr_store+0x20/0x30 [ 87.875442] sysfs_kf_write+0x54/0x64 [ 87.879618] kernfs_fop_write+0xe4/0x1e8 [ 87.884055] __vfs_write+0x40/0x184 [ 87.888057] vfs_write+0xa8/0x19c [ 87.891887] ksys_write+0x58/0xbc [ 87.895716] __arm64_sys_write+0x18/0x20 [ 87.900154] el0_svc_common+0xd0/0x124 [ 87.904417] el0_svc_compat_handler+0x1c/0x24 [ 87.909289] el0_svc_compat+0x8/0x18 [ 87.913378] [ 87.913378] other info that might help us debug this: [ 87.913378] [ 87.921374] Possible unsafe locking scenario: [ 87.921374] [ 87.927286] CPU0 CPU1 [ 87.931808] ---- ---- [ 87.936331] lock(pwm_lock); [ 87.939293] lock(kn->count#58); [ 87.945120] lock(pwm_lock); [ 87.950599] lock(kn->count#58); [ 87.953908] [ 87.953908] *** DEADLOCK *** [ 87.953908] [ 87.959821] 4 locks held by bash/2986: [ 87.963563] #0: 00000000ace7bc30 (sb_writers#6){.+.+}, at: vfs_write+0x188/0x19c [ 87.971044] #1: 00000000287991b2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xb4/0x1e8 [ 87.978872] #2: 00000000f739d016 (&dev->mutex){....}, at: device_release_driver_internal+0x40/0x21c [ 87.988001] #3: 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.995481] [ 87.995481] stack backtrace: [ 87.999836] CPU: 0 PID: 2986 Comm: bash Not tainted 5.0.0 #7 [ 88.005489] Hardware name: Renesas Salvator-X board based on r8a7795 ES1.x (DT) [ 88.012791] Call trace: [ 88.015235] dump_backtrace+0x0/0x190 [ 88.018891] show_stack+0x14/0x1c [ 88.022204] dump_stack+0xb0/0xec [ 88.025514] print_circular_bug.isra.32+0x1d0/0x2e0 [ 88.030385] __lock_acquire+0x1318/0x1864 [ 88.034388] lock_acquire+0xc4/0x22c [ 88.037958] __kernfs_remove+0x258/0x2c4 [ 88.041874] kernfs_remove_by_name_ns+0x50/0xa0 [ 88.046398] remove_files.isra.1+0x38/0x78 [ 88.050487] sysfs_remove_group+0x48/0x98 [ 88.054490] sysfs_remove_groups+0x34/0x4c [ 88.058580] device_remove_attrs+0x6c/0x7c [ 88.062671] device_del+0x11c/0x33c [ 88.066154] device_unregister+0x14/0x2c [ 88.070070] pwmchip_sysfs_unexport+0x40/0x4c [ 88.074421] pwmchip_remove+0xf4/0x13c [ 88.078163] rcar_pwm_remove+0x28/0x34 [ 88.081906] platform_drv_remove+0x24/0x64 [ 88.085996] device_release_driver_internal+0x18c/0x21c [ 88.091215] device_release_driver+0x14/0x1c [ 88.095478] unbind_store+0xe0/0x124 [ 88.099048] drv_attr_store+0x20/0x30 [ 88.102704] sysfs_kf_write+0x54/0x64 [ 88.106359] kernfs_fop_write+0xe4/0x1e8 [ 88.110275] __vfs_write+0x40/0x184 [ 88.113757] vfs_write+0xa8/0x19c [ 88.117065] ksys_write+0x58/0xbc [ 88.120374] __arm64_sys_write+0x18/0x20 [ 88.124291] el0_svc_common+0xd0/0x124 [ 88.128034] el0_svc_compat_handler+0x1c/0x24 [ 88.132384] el0_svc_compat+0x8/0x18 The sysfs unexport in pwmchip_remove() is completely asymmetric to what we do in pwmchip_add_with_polarity() and commit 0733424c9ba9 ("pwm: Unexport children before chip removal") is a strong indication that this was wrong to begin with. We should just move pwmchip_sysfs_unexport() where it belongs, which is right after pwmchip_sysfs_unexport_children(). In that case, we do not need separate functions anymore either. We also really want to remove sysfs irrespective of whether or not the chip will be removed as a result of pwmchip_remove(). We can only assume that the driver will be gone after that, so we shouldn't leave any dangling sysfs files around. This warning disappears if we move pwmchip_sysfs_unexport() to the top of pwmchip_remove(), pwmchip_sysfs_unexport_children(). That way it is also outside of the pwm_lock section, which indeed doesn't seem to be needed. Moving the pwmchip_sysfs_export() call outside of that section also seems fine and it'd be perfectly symmetric with pwmchip_remove() again. So, this patch fixes them. Signed-off-by: Phong Hoang <phong.hoang.wz@renesas.com> [shimoda: revise the commit log and code] Fixes: 76abbdde2d95 ("pwm: Add sysfs interface") Fixes: 0733424c9ba9 ("pwm: Unexport children before chip removal") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Tested-by: Hoan Nguyen An <na-hoan@jinso.co.jp> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* x86/power: Fix 'nosmt' vs hibernation triple fault during resumeJiri Kosina2019-06-111-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ec527c318036a65a083ef68d8ba95789d2212246 upstream. As explained in 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") we always, no matter what, have to bring up x86 HT siblings during boot at least once in order to avoid first MCE bringing the system to its knees. That means that whenever 'nosmt' is supplied on the kernel command-line, all the HT siblings are as a result sitting in mwait or cpudile after going through the online-offline cycle at least once. This causes a serious issue though when a kernel, which saw 'nosmt' on its commandline, is going to perform resume from hibernation: if the resume from the hibernated image is successful, cr3 is flipped in order to point to the address space of the kernel that is being resumed, which in turn means that all the HT siblings are all of a sudden mwaiting on address which is no longer valid. That results in triple fault shortly after cr3 is switched, and machine reboots. Fix this by always waking up all the SMT siblings before initiating the 'restore from hibernation' process; this guarantees that all the HT siblings will be properly carried over to the resumed kernel waiting in resume_play_dead(), and acted upon accordingly afterwards, based on the target kernel configuration. Symmetricaly, the resumed kernel has to push the SMT siblings to mwait again in case it has SMT disabled; this means it has to online all the siblings when resuming (so that they come out of hlt) and offline them again to let them reach mwait. Cc: 4.19+ <stable@vger.kernel.org> # v4.19+ Debugged-by: Thomas Gleixner <tglx@linutronix.de> Fixes: 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Pavel Machek <pavel@ucw.cz> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* pstore: Convert buf_lock to semaphoreKees Cook2019-06-111-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ea84b580b95521644429cc6748b6c2bf27c8b0f3 upstream. Instead of running with interrupts disabled, use a semaphore. This should make it easier for backends that may need to sleep (e.g. EFI) when performing a write: |BUG: sleeping function called from invalid context at kernel/sched/completion.c:99 |in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum |Preemption disabled at: |[<ffffffff99d60512>] pstore_dump+0x72/0x330 |CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45 |Call Trace: | dump_stack+0x4f/0x6a | ___might_sleep.cold.91+0xd3/0xe4 | __might_sleep+0x50/0x90 | wait_for_completion+0x32/0x130 | virt_efi_query_variable_info+0x14e/0x160 | efi_query_variable_store+0x51/0x1a0 | efivar_entry_set_safe+0xa3/0x1b0 | efi_pstore_write+0x109/0x140 | pstore_dump+0x11c/0x330 | kmsg_dump+0xa4/0xd0 | oops_exit+0x22/0x30 ... Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Fixes: 21b3ddd39fee ("efi: Don't use spinlocks for efi vars") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* rcu: locking and unlocking need to always be at least barriersLinus Torvalds2019-06-111-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 66be4e66a7f422128748e3c3ef6ee72b20a6197b upstream. Herbert Xu pointed out that commit bb73c52bad36 ("rcu: Don't disable preemption for Tiny and Tree RCU readers") was incorrect in making the preempt_disable/enable() be conditional on CONFIG_PREEMPT_COUNT. If CONFIG_PREEMPT_COUNT isn't enabled, the preemption enable/disable is a no-op, but still is a compiler barrier. And RCU locking still _needs_ that compiler barrier. It is simply fundamentally not true that RCU locking would be a complete no-op: we still need to guarantee (for example) that things that can trap and cause preemption cannot migrate into the RCU locked region. The way we do that is by making it a barrier. See for example commit 386afc91144b ("spinlocks and preemption points need to be at least compiler barriers") from back in 2013 that had similar issues with spinlocks that become no-ops on UP: they must still constrain the compiler from moving other operations into the critical region. Now, it is true that a lot of RCU operations already use READ_ONCE() and WRITE_ONCE() (which in practice likely would never be re-ordered wrt anything remotely interesting), but it is also true that that is not globally the case, and that it's not even necessarily always possible (ie bitfields etc). Reported-by: Herbert Xu <herbert@gondor.apana.org.au> Fixes: bb73c52bad36 ("rcu: Don't disable preemption for Tiny and Tree RCU readers") Cc: stable@kernel.org Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>