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2017-04-04nvmet-rdma: use generic inet_pton_with_scopeSagi Grimberg
Instead of parsing address strings, use a generic helper. This also adds ipv6 (with address scopes) support. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04net/utils: generic inet_pton_with_scope helperSagi Grimberg
Several locations in the stack need to handle ipv4/ipv6 (with scope) and port strings conversion to sockaddr. Add a helper that takes either AF_INET, AF_INET6 or AF_UNSPEC (for wildcard) to centralize this handling. Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvme-loop: remove some code duplicationSagi Grimberg
Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvme-rdma: Give some more grace for rdma connection establishmentSagi Grimberg
The target might be occupied with multiple hosts so lets give it some more grace before failing the connection establishment. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvmet-rdma: occasionally flush ongoing controller teardownSagi Grimberg
If we are attacked with establishments/teradowns we need to make sure we do not consume too much system memory. Thus let ongoing controller teardowns complete before accepting new controller establishments. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvme-rdma: handle cpu unplug when re-establishing the controllerSagi Grimberg
If a cpu unplug event has occured, we need to take the minimum of the provided nr_io_queues and the number of online cpus, otherwise we won't be able to connect them as blk-mq mapping won't dispatch to those queues. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvmet-rdma: Fix a possible uninitialized variable dereferenceSagi Grimberg
When handling a new recv command, we grab a new rsp resource and check for the queue state being live. In case the queue is not in live state, we simply restore the rsp back to the free list. However in this flow we didn't set rsp->queue yet, so we cannot dereference it. Instead, make sure to initialize rsp->queue (and other rsp members) as soon as possible so we won't reference uninitialized variables. Reported-by: Yi Zhang <yizhan@redhat.com> Reported-by: Raju Rangoju <rajur@chelsio.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Raju Rangoju <rajur@chelsio.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvmet: confirm sq percpu has scheduled and switched to atomicSagi Grimberg
percpu_ref_kill is not enough to prevent subsequent percpu_ref_tryget_live from failing. Hence call perfcpu_ref_kill_confirm to make it safe. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04nvme-loop: handle cpu unplug when re-establishing the controllerSagi Grimberg
If a cpu unplug event has occured, we need to take the minimum of the provided nr_io_queues and the number of online cpus, otherwise we won't be able to connect them as blk-mq mapping won't dispatch to those queues. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04nvme-loop: fix a possible use-after-free when destroying the admin queueSagi Grimberg
we need to destroy the nvmet sq and let it finish gracefully before continue to cleanup the queue. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04Merge branch 'nvme-4.11-rc' of git://git.infradead.org/nvme into for-linusJens Axboe
Sagi writes: We have one spec mis-match fix from Roland and several sparse fixes from Christoph.
2017-04-02nvmet: fix byte swap in nvmet_parse_io_cmdChristoph Hellwig
We need to do arithmetics after byte swapping, not before. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02nvmet: fix byte swap in nvmet_execute_write_zeroesChristoph Hellwig
The length field in the Write Zeroes command is a 16-bit field. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02nvmet: add missing byte swap in nvmet_get_smart_logChristoph Hellwig
In this case entirely harmless as it's all-ones, but still nice to shut up sparse. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02nvme: add missing byte swap in nvme_setup_discardChristoph Hellwig
Fixes: b35ba01e ("nvme: support ranged discard requests") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02nvme: Correct NVMF enum values to match NVMe-oF rev 1.0Roland Dreier
The enum values for QPTYPE, PRTYPE and CMS are off by 1 from the values defined in figure 42 of the NVM Express over Fabrics 1.0: http://www.nvmexpress.org/wp-content/uploads/NVMe_over_Fabrics_1_0_Gold_20160605-1.pdf Fix our enums to match the final spec. Signed-off-by: Roland Dreier <roland@purestorage.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-03-31blk-mq: constify struct blk_mq_opsEric Biggers
Constify all instances of blk_mq_ops, as they are never modified. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30null_blk: add blocking modeJens Axboe
This adds a new module parameter to null_blk, blocking. If set, null_blk will set the BLK_MQ_F_BLOCKING flag, indicating that it sometimes/always needs to block in its ->queue_rq() function. The intent is to help find regressions in blocking drivers, since not many of them exist. If null_blk is loaded with submit_queues > 1 and blocking=1, this shows the regression recently fixed by bf4907c05e61. Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30blk-mq: fix schedule-under-preempt for blocking driversJens Axboe
Commit a4d907b6a33b unified the single and multi queue request handlers, but in the process, it also screwed up the locking balance and calls blk_mq_try_issue_directly() with the ctx preempt lock held. This is a problem for drivers that have set BLK_MQ_F_BLOCKING, since now they can't reliably sleep. While in there, protect against similar issues in the future, by adding a might_sleep() trigger in the BLOCKING path for direct issue or queue run. Reported-by: Josef Bacik <josef@toxicpanda.com> Tested-by: Josef Bacik <josef@toxicpanda.com> Fixes: a4d907b6a33b ("blk-mq: streamline blk_mq_make_request") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30block/sed-opal: fix spelling mistake: "Lifcycle" -> "Lifecycle"Colin Ian King
trivial fix to spelling mistake in pr_err error message Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30block: do not put mq context in blk_mq_alloc_request_hctxMinchan Kim
In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't get sw context so we don't need to put the context with blk_mq_put_ctx. Unless, we will see preempt counter underflow. Cc: Omar Sandoval <osandov@fb.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30block: do not put mq context in blk_mq_alloc_request_hctxMinchan Kim
In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't get sw context so we don't need to put the context with blk_mq_put_ctx. Unless, we will see preempt counter underflow. Cc: Omar Sandoval <osandov@fb.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29Merge branch 'for-rc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux Pull thermal management fixes from Zhang Rui: - Fix a potential deadlock in cpu_cooling driver, which was introduced in 4.11-rc1. (Matthew Wilcox) - Fix the cpu_cooling and devfreq_cooling code to handle possible error return value from OPP calls, together with three minor fixes in the same patch series. (Viresh Kumar) * 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: thermal: cpu_cooling: Check OPP for errors thermal: cpu_cooling: Replace dev_warn with dev_err thermal: devfreq: Check OPP for errors thermal: devfreq_cooling: Replace dev_warn with dev_err thermal: devfreq: Simplify expression thermal: Fix potential deadlock in cpu_cooling
2017-03-29Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Five fixes for this series: - a fix from me to ensure that blk-mq drivers that terminate IO in their ->queue_rq() handler by returning QUEUE_ERROR don't stall with a scheduler enabled. - four nbd fixes from Josef and Ratna, fixing various problems that are critical enough to go in for this cycle. They have been well tested" * 'for-linus' of git://git.kernel.dk/linux-block: nbd: replace kill_bdev() with __invalidate_device() nbd: set queue timeout properly nbd: set rq->errors to actual error code nbd: handle ERESTARTSYS properly blk-mq: include errors in did_work calculation
2017-03-29Merge branch 'apw' (xfrm_user fixes)Linus Torvalds
Merge xfrm_user validation fixes from Andy Whitcroft: "Two patches we are applying to Ubuntu for XFRM_MSG_NEWAE validation issue reported by ZDI. The first of these is the primary fix, and the second is for a more theoretical issue that Kees pointed out when reviewing the first" * emailed patches from Andy Whitcroft <apw@canonical.com>: xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harder xfrm_user: validate XFRM_MSG_NEWAE XFRMA_REPLAY_ESN_VAL replay_window
2017-03-29blk-mq: include errors in did_work calculationJens Axboe
Currently we return true in blk_mq_dispatch_rq_list() if we queued IO successfully, but we really want to return whether or not the we made progress. Progress includes if we got an error return. If we don't, this can lead to a hang in blk_mq_sched_dispatch_requests() when a driver is draining IO by returning BLK_MQ_QUEUE_ERROR instead of manually ending the IO in error and return BLK_MQ_QUEUE_OK. Tested-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29block-mq: don't re-queue if we get a queue errorJosef Bacik
When try to issue a request directly and we fail we will requeue the request, but call blk_mq_end_request() as well. This leads to the completed request being on a queuelist and getting ended twice, which causes list corruption in schedulers and other shenanigans. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29blkcg: allocate struct blkcg_gq outside request queue spinlockTahsin Erdogan
blkg_conf_prep() currently calls blkg_lookup_create() while holding request queue spinlock. This means allocating memory for struct blkcg_gq has to be made non-blocking. This causes occasional -ENOMEM failures in call paths like below: pcpu_alloc+0x68f/0x710 __alloc_percpu_gfp+0xd/0x10 __percpu_counter_init+0x55/0xc0 cfq_pd_alloc+0x3b2/0x4e0 blkg_alloc+0x187/0x230 blkg_create+0x489/0x670 blkg_lookup_create+0x9a/0x230 blkg_conf_prep+0x1fb/0x240 __cfqg_set_weight_device.isra.105+0x5c/0x180 cfq_set_weight_on_dfl+0x69/0xc0 cgroup_file_write+0x39/0x1c0 kernfs_fop_write+0x13f/0x1d0 __vfs_write+0x23/0x120 vfs_write+0xc2/0x1f0 SyS_write+0x44/0xb0 entry_SYSCALL_64_fastpath+0x18/0xad In the code path above, percpu allocator cannot call vmalloc() due to queue spinlock. A failure in this call path gives grief to tools which are trying to configure io weights. We see occasional failures happen shortly after reboots even when system is not under any memory pressure. Machines with a lot of cpus are more vulnerable to this condition. Do struct blkcg_gq allocations outside the queue spinlock to allow blocking during memory allocations. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Tahsin Erdogan <tahsin@google.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29Revert "blkcg: allocate struct blkcg_gq outside request queue spinlock"Jens Axboe
I inadvertently applied the v5 version of this patch, whereas the agreed upon version was v5. Revert this one so we can apply the right one. This reverts commit 7fc6b87a9ff537e7df32b1278118ce9c5bcd6788.
2017-03-29blk-mq: fix a typo and a spelling mistakeJens Axboe
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29blk-mq-pci: Fix two spelling mistakesSagi Grimberg
Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29Merge branch 'regset' (PTRACE_SETREGSET data leakage)Linus Torvalds
Merge PTRACE_SETREGSET leakage fixes from Dave Martin: "This series is the collection of fixes I proposed on this topic, that have not yet appeared upstream or in the stable branches, The issue can leak kernel stack, but doesn't appear to allow userspace to attack the kernel directly. The affected architectures are c6x, h8300, metag, mips and sparc. [ Mark Salter points out that c6x has no MMU or other mechanism to prevent userspace access to kernel code or data on c6x, but it doesn't hurt to clean that case up too. ] The bugs arise from use of user_regset_copyin(). Users of user_regset_copyin() can work in one of two ways: 1) Copy directly to thread_struct or equivalent. (This seems to be the design assumption of the regset API, and is the most common approach.) 2) Copy to a local variable and then transfer to thread_struct. (A significant minority of cases.) Buggy code typically involves approach 2" * emailed patches from Dave Martin <Dave.Martin@arm.com>: sparc/ptrace: Preserve previous registers for short regset write mips/ptrace: Preserve previous registers for short regset write metag/ptrace: Reject partial NT_METAG_RPIPE writes metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS metag/ptrace: Preserve previous registers for short regset write h8300/ptrace: Fix incorrect register transfer count c6x/ptrace: Remove useless PTRACE_SETREGSET implementation
2017-03-29sparc/ptrace: Preserve previous registers for short regset writeDave Martin
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29mips/ptrace: Preserve previous registers for short regset writeDave Martin
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29metag/ptrace: Reject partial NT_METAG_RPIPE writesDave Martin
It's not clear what behaviour is sensible when doing partial write of NT_METAG_RPIPE, so just don't bother. This patch assumes that userspace will never rely on a partial SETREGSET in this case, since it's not clear what should happen anyway. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUSDave Martin
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill TXSTATUS, a well-defined default value is used, based on the task's current value. Suggested-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29metag/ptrace: Preserve previous registers for short regset writeDave Martin
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29h8300/ptrace: Fix incorrect register transfer countDave Martin
regs_set() and regs_get() are vulnerable to an off-by-1 buffer overrun if CONFIG_CPU_H8S is set, since this adds an extra entry to register_offset[] but not to user_regs_struct. So, iterate over user_regs_struct based on its actual size, not based on the length of register_offset[]. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29c6x/ptrace: Remove useless PTRACE_SETREGSET implementationDave Martin
gpr_set won't work correctly and can never have been tested, and the correct behaviour is not clear due to the endianness-dependent task layout. So, just remove it. The core code will now return -EOPNOTSUPPORT when trying to set NT_PRSTATUS on this architecture until/unless a correct implementation is supplied. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harderAndy Whitcroft
Kees Cook has pointed out that xfrm_replay_state_esn_len() is subject to wrapping issues. To ensure we are correctly ensuring that the two ESN structures are the same size compare both the overall size as reported by xfrm_replay_state_esn_len() and the internal length are the same. CVE-2017-7184 Signed-off-by: Andy Whitcroft <apw@canonical.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29xfrm_user: validate XFRM_MSG_NEWAE XFRMA_REPLAY_ESN_VAL replay_windowAndy Whitcroft
When a new xfrm state is created during an XFRM_MSG_NEWSA call we validate the user supplied replay_esn to ensure that the size is valid and to ensure that the replay_window size is within the allocated buffer. However later it is possible to update this replay_esn via a XFRM_MSG_NEWAE call. There we again validate the size of the supplied buffer matches the existing state and if so inject the contents. We do not at this point check that the replay_window is within the allocated memory. This leads to out-of-bounds reads and writes triggered by netlink packets. This leads to memory corruption and the potential for priviledge escalation. We already attempt to validate the incoming replay information in xfrm_new_ae() via xfrm_replay_verify_len(). This confirms that the user is not trying to change the size of the replay state buffer which includes the replay_esn. It however does not check the replay_window remains within that buffer. Add validation of the contained replay_window. CVE-2017-7184 Signed-off-by: Andy Whitcroft <apw@canonical.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-29block: fix leak of q->rq_wbOmar Sandoval
CONFIG_DEBUG_TEST_DRIVER_REMOVE found a possible leak of q->rq_wb when a request queue is reregistered. This has been a problem since wbt was introduced, but the WARN_ON(!list_empty(&stats->callbacks)) in the blk-stat rework exposed it. Fix it by cleaning up wbt when we unregister the queue. Fixes: 87760e5eef35 ("block: hook up writeback throttling") Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29blk-mq: fix leak of q->statsOmar Sandoval
blk_alloc_queue_node() already allocates q->stats, so blk_mq_init_allocated_queue() is overwriting it with a new allocation. Fixes: a83b576c9c25 ("block: fix stacked driver stats init and free") Reviewed-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29block: warn if sharing request queue across gendisksOmar Sandoval
Now that the remaining drivers have been converted to one request queue per gendisk, let's warn if a request queue gets registered more than once. This will catch future drivers which might do it inadvertently or any old drivers that I may have missed. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29block: block new I/O just after queue is set as dyingMing Lei
Before commit 780db2071a(blk-mq: decouble blk-mq freezing from generic bypassing), the dying flag is checked before entering queue, and Tejun converts the checking into .mq_freeze_depth, and assumes the counter is increased just after dying flag is set. Unfortunately we doesn't do that in blk_set_queue_dying(). This patch calls blk_freeze_queue_start() in blk_set_queue_dying(), so that we can block new I/O coming once the queue is set as dying. Given blk_set_queue_dying() is always called in remove path of block device, and queue will be cleaned up later, we don't need to worry about undoing the counter. Cc: Tejun Heo <tj@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29block: rename blk_mq_freeze_queue_start()Ming Lei
As the .q_usage_counter is used by both legacy and mq path, we need to block new I/O if queue becomes dead in blk_queue_enter(). So rename it and we can use this function in both paths. Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29block: add a read barrier in blk_queue_enter()Ming Lei
Without the barrier, reading DEAD flag of .q_usage_counter and reading .mq_freeze_depth may be reordered, then the following wait_event_interruptible() may never return. Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29blk-mq: comment on races related with timeout handlerMing Lei
This patch adds comment on two races related with timeout handler: - requeue from queue busy vs. timeout - rq free & reallocation vs. timeout Both the races themselves and current solution aren't explicit enough, so add comments on them. Cc: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29blk-mq: don't complete un-started request in timeout handlerMing Lei
When iterating busy requests in timeout handler, if the STARTED flag of one request isn't set, that means the request is being processed in block layer or driver, and isn't submitted to hardware yet. In current implementation of blk_mq_check_expired(), if the request queue becomes dying, un-started requests are handled as being completed/freed immediately. This way is wrong, and can cause rq corruption or double allocation[1][2], when doing I/O and removing&resetting NVMe device at the sametime. This patch fixes several issues reported by Yi Zhang. [1]. oops log 1 [ 581.789754] ------------[ cut here ]------------ [ 581.789758] kernel BUG at block/blk-mq.c:374! [ 581.789760] invalid opcode: 0000 [#1] SMP [ 581.789761] Modules linked in: vfat fat ipmi_ssif intel_rapl sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm nvme irqbypass crct10dif_pclmul nvme_core crc32_pclmul ghash_clmulni_intel intel_cstate ipmi_si mei_me ipmi_devintf intel_uncore sg ipmi_msghandler intel_rapl_perf iTCO_wdt mei iTCO_vendor_support mxm_wmi lpc_ich dcdbas shpchp pcspkr acpi_power_meter wmi nfsd auth_rpcgss nfs_acl lockd dm_multipath grace sunrpc ip_tables xfs libcrc32c sd_mod mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm ahci libahci crc32c_intel tg3 libata megaraid_sas i2c_core ptp fjes pps_core dm_mirror dm_region_hash dm_log dm_mod [ 581.789796] CPU: 1 PID: 1617 Comm: kworker/1:1H Not tainted 4.10.0.bz1420297+ #4 [ 581.789797] Hardware name: Dell Inc. PowerEdge R730xd/072T6D, BIOS 2.2.5 09/06/2016 [ 581.789804] Workqueue: kblockd blk_mq_timeout_work [ 581.789806] task: ffff8804721c8000 task.stack: ffffc90006ee4000 [ 581.789809] RIP: 0010:blk_mq_end_request+0x58/0x70 [ 581.789810] RSP: 0018:ffffc90006ee7d50 EFLAGS: 00010202 [ 581.789811] RAX: 0000000000000001 RBX: ffff8802e4195340 RCX: ffff88028e2f4b88 [ 581.789812] RDX: 0000000000001000 RSI: 0000000000001000 RDI: 0000000000000000 [ 581.789813] RBP: ffffc90006ee7d60 R08: 0000000000000003 R09: ffff88028e2f4b00 [ 581.789814] R10: 0000000000001000 R11: 0000000000000001 R12: 00000000fffffffb [ 581.789815] R13: ffff88042abe5780 R14: 000000000000002d R15: ffff88046fbdff80 [ 581.789817] FS: 0000000000000000(0000) GS:ffff88047fc00000(0000) knlGS:0000000000000000 [ 581.789818] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 581.789819] CR2: 00007f64f403a008 CR3: 000000014d078000 CR4: 00000000001406e0 [ 581.789820] Call Trace: [ 581.789825] blk_mq_check_expired+0x76/0x80 [ 581.789828] bt_iter+0x45/0x50 [ 581.789830] blk_mq_queue_tag_busy_iter+0xdd/0x1f0 [ 581.789832] ? blk_mq_rq_timed_out+0x70/0x70 [ 581.789833] ? blk_mq_rq_timed_out+0x70/0x70 [ 581.789840] ? __switch_to+0x140/0x450 [ 581.789841] blk_mq_timeout_work+0x88/0x170 [ 581.789845] process_one_work+0x165/0x410 [ 581.789847] worker_thread+0x137/0x4c0 [ 581.789851] kthread+0x101/0x140 [ 581.789853] ? rescuer_thread+0x3b0/0x3b0 [ 581.789855] ? kthread_park+0x90/0x90 [ 581.789860] ret_from_fork+0x2c/0x40 [ 581.789861] Code: 48 85 c0 74 0d 44 89 e6 48 89 df ff d0 5b 41 5c 5d c3 48 8b bb 70 01 00 00 48 85 ff 75 0f 48 89 df e8 7d f0 ff ff 5b 41 5c 5d c3 <0f> 0b e8 71 f0 ff ff 90 eb e9 0f 1f 40 00 66 2e 0f 1f 84 00 00 [ 581.789882] RIP: blk_mq_end_request+0x58/0x70 RSP: ffffc90006ee7d50 [ 581.789889] ---[ end trace bcaf03d9a14a0a70 ]--- [2]. oops log2 [ 6984.857362] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 [ 6984.857372] IP: nvme_queue_rq+0x6e6/0x8cd [nvme] [ 6984.857373] PGD 0 [ 6984.857374] [ 6984.857376] Oops: 0000 [#1] SMP [ 6984.857379] Modules linked in: ipmi_ssif vfat fat intel_rapl sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel ipmi_si iTCO_wdt iTCO_vendor_support mxm_wmi ipmi_devintf intel_cstate sg dcdbas intel_uncore mei_me intel_rapl_perf mei pcspkr lpc_ich ipmi_msghandler shpchp acpi_power_meter wmi nfsd auth_rpcgss dm_multipath nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect crc32c_intel sysimgblt fb_sys_fops ttm nvme drm nvme_core ahci libahci i2c_core tg3 libata ptp megaraid_sas pps_core fjes dm_mirror dm_region_hash dm_log dm_mod [ 6984.857416] CPU: 7 PID: 1635 Comm: kworker/7:1H Not tainted 4.10.0-2.el7.bz1420297.x86_64 #1 [ 6984.857417] Hardware name: Dell Inc. PowerEdge R730xd/072T6D, BIOS 2.2.5 09/06/2016 [ 6984.857427] Workqueue: kblockd blk_mq_run_work_fn [ 6984.857429] task: ffff880476e3da00 task.stack: ffffc90002e90000 [ 6984.857432] RIP: 0010:nvme_queue_rq+0x6e6/0x8cd [nvme] [ 6984.857433] RSP: 0018:ffffc90002e93c50 EFLAGS: 00010246 [ 6984.857434] RAX: 0000000000000000 RBX: ffff880275646600 RCX: 0000000000001000 [ 6984.857435] RDX: 0000000000000fff RSI: 00000002fba2a000 RDI: ffff8804734e6950 [ 6984.857436] RBP: ffffc90002e93d30 R08: 0000000000002000 R09: 0000000000001000 [ 6984.857437] R10: 0000000000001000 R11: 0000000000000000 R12: ffff8804741d8000 [ 6984.857438] R13: 0000000000000040 R14: ffff880475649f80 R15: ffff8804734e6780 [ 6984.857439] FS: 0000000000000000(0000) GS:ffff88047fcc0000(0000) knlGS:0000000000000000 [ 6984.857440] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6984.857442] CR2: 0000000000000010 CR3: 0000000001c09000 CR4: 00000000001406e0 [ 6984.857443] Call Trace: [ 6984.857451] ? mempool_free+0x2b/0x80 [ 6984.857455] ? bio_free+0x4e/0x60 [ 6984.857459] blk_mq_dispatch_rq_list+0xf5/0x230 [ 6984.857462] blk_mq_process_rq_list+0x133/0x170 [ 6984.857465] __blk_mq_run_hw_queue+0x8c/0xa0 [ 6984.857467] blk_mq_run_work_fn+0x12/0x20 [ 6984.857473] process_one_work+0x165/0x410 [ 6984.857475] worker_thread+0x137/0x4c0 [ 6984.857478] kthread+0x101/0x140 [ 6984.857480] ? rescuer_thread+0x3b0/0x3b0 [ 6984.857481] ? kthread_park+0x90/0x90 [ 6984.857489] ret_from_fork+0x2c/0x40 [ 6984.857490] Code: 8b bd 70 ff ff ff 89 95 50 ff ff ff 89 8d 58 ff ff ff 44 89 95 60 ff ff ff e8 b7 dd 12 e1 8b 95 50 ff ff ff 48 89 85 68 ff ff ff <4c> 8b 48 10 44 8b 58 18 8b 8d 58 ff ff ff 44 8b 95 60 ff ff ff [ 6984.857511] RIP: nvme_queue_rq+0x6e6/0x8cd [nvme] RSP: ffffc90002e93c50 [ 6984.857512] CR2: 0000000000000010 [ 6984.895359] ---[ end trace 2d7ceb528432bf83 ]--- Cc: stable@vger.kernel.org Reported-by: Yi Zhang <yizhan@redhat.com> Tested-by: Yi Zhang <yizhan@redhat.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-28blkcg: allocate struct blkcg_gq outside request queue spinlockTahsin Erdogan
blkg_conf_prep() currently calls blkg_lookup_create() while holding request queue spinlock. This means allocating memory for struct blkcg_gq has to be made non-blocking. This causes occasional -ENOMEM failures in call paths like below: pcpu_alloc+0x68f/0x710 __alloc_percpu_gfp+0xd/0x10 __percpu_counter_init+0x55/0xc0 cfq_pd_alloc+0x3b2/0x4e0 blkg_alloc+0x187/0x230 blkg_create+0x489/0x670 blkg_lookup_create+0x9a/0x230 blkg_conf_prep+0x1fb/0x240 __cfqg_set_weight_device.isra.105+0x5c/0x180 cfq_set_weight_on_dfl+0x69/0xc0 cgroup_file_write+0x39/0x1c0 kernfs_fop_write+0x13f/0x1d0 __vfs_write+0x23/0x120 vfs_write+0xc2/0x1f0 SyS_write+0x44/0xb0 entry_SYSCALL_64_fastpath+0x18/0xad In the code path above, percpu allocator cannot call vmalloc() due to queue spinlock. A failure in this call path gives grief to tools which are trying to configure io weights. We see occasional failures happen shortly after reboots even when system is not under any memory pressure. Machines with a lot of cpus are more vulnerable to this condition. Update blkg_create() function to temporarily drop the rcu and queue locks when it is allowed by gfp mask. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Tahsin Erdogan <tahsin@google.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>