Two different callers use two different mutexes for updating the
block device size, which obviously doesn't help to actually protect
against concurrent updates from the different callers.  In addition
one of the locks, bd_mutex is rather prone to deadlocks with other
parts of the block stack that use it for high level synchronization.

Switch to using a new spinlock protecting just the size updates, as
that is all we need, and make sure everyone does the update through
the proper helper.

This fixes a bug reported with the nvme revalidating disks during a
hot removal operation, which can currently deadlock on bd_mutex.
Reported-by: Xianting Tian <xianting_tian@126.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Replace bd_set_size with a version that takes the number of sectors
instead, as that fits most of the current and future callers much better.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

request_queue.rpm_status is assigned values of the rpm_status enum only,
so reflect that in its type.

Note that including <linux/pm.h> is (currently) a no-op, as it is
already included through <linux/genhd.h> and <linux/device.h>, but it is
better to play it safe.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

* block-5.9:
  blk-stat: make q->stats->lock irqsafe
  blk-iocost: ioc_pd_free() shouldn't assume irq disabled
  block: fix locking in bdev_del_partition
  block: release disk reference in hd_struct_free_work
  block: ensure bdi->io_pages is always initialized
  nvme-pci: cancel nvme device request before disabling
  nvme: only use power of two io boundaries
  nvme: fix controller instance leak
  nvmet-fc: Fix a missed _irqsave version of spin_lock in 'nvmet_fc_fod_op_done()'
  nvme: Fix NULL dereference for pci nvme controllers
  nvme-rdma: fix reset hang if controller died in the middle of a reset
  nvme-rdma: fix timeout handler
  nvme-rdma: serialize controller teardown sequences
  nvme-tcp: fix reset hang if controller died in the middle of a reset
  nvme-tcp: fix timeout handler
  nvme-tcp: serialize controller teardown sequences
  nvme: have nvme_wait_freeze_timeout return if it timed out
  nvme-fabrics: don't check state NVME_CTRL_NEW for request acceptance
  nvmet-tcp: Fix NULL dereference when a connect data comes in h2cdata pdu

blk-iocost calls blk_stat_enable_accounting() while holding an irqsafe lock
which triggers a lockdep splat because q->stats->lock isn't irqsafe. Let's
make it irqsafe.
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: cd006509 ("blk-iocost: account for IO size when testing latencies")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ioc_pd_free() grabs irq-safe ioc->lock without ensuring that irq is disabled
when it can be called with irq disabled or enabled. This has a small chance
of causing A-A deadlocks and triggers lockdep splats. Use irqsave operations
instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 7caa4715 ("blkcg: implement blk-iocost")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We need to hold the whole device bd_mutex to protect against
other thread concurrently deleting out partition before we get
to it, and thus causing a use after free.

Fixes: cddae808 ("block: pass a hd_struct to delete_partition")
Reported-by: syzbot+6448f3c229bc52b82f69@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Commit e8c7d14a ("block: revert back to synchronous request_queue removal")
stops to release request queue from wq context because that commit
supposed all blk_put_queue() is called in context which is allowed
to sleep. However, this assumption isn't true because we release disk's
reference in partition's percpu_ref's ->release() which doesn't allow
to sleep, because the ->release() is run via call_rcu().

Fixes this issue by moving put disk reference into hd_struct_free_work()

Fixes: e8c7d14a ("block: revert back to synchronous request_queue removal")
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If a driver leaves the limit settings as the defaults, then we don't
initialize bdi->io_pages. This means that file systems may need to
work around bdi->io_pages == 0, which is somewhat messy.

Initialize the default value just like we do for ->ra_pages.

Cc: stable@vger.kernel.org
Fixes: 9491ae4a ("mm: don't cap request size based on read-ahead setting")
Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull crypto fixes from Herbert Xu:

 - fix regression in af_alg that affects iwd

 - restore polling delay in qat

 - fix double free in ingenic on error path

 - fix potential build failure in sa2ul due to missing Kconfig dependency

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: af_alg - Work around empty control messages without MSG_MORE
  crypto: sa2ul - add Kconfig selects to fix build error
  crypto: ingenic - Drop kfree for memory allocated with devm_kzalloc
  crypto: qat - add delay before polling mailbox

Pull x86 fixes from Thomas Gleixner:
 "Three interrupt related fixes for X86:

   - Move disabling of the local APIC after invoking fixup_irqs() to
     ensure that interrupts which are incoming are noted in the IRR and
     not ignored.

   - Unbreak affinity setting.

     The rework of the entry code reused the regular exception entry
     code for device interrupts. The vector number is pushed into the
     errorcode slot on the stack which is then lifted into an argument
     and set to -1 because that's regs->orig_ax which is used in quite
     some places to check whether the entry came from a syscall.

     But it was overlooked that orig_ax is used in the affinity cleanup
     code to validate whether the interrupt has arrived on the new
     target. It turned out that this vector check is pointless because
     interrupts are never moved from one vector to another on the same
     CPU. That check is a historical leftover from the time where x86
     supported multi-CPU affinities, but not longer needed with the now
     strict single CPU affinity. Famous last words ...

   - Add a missing check for an empty cpumask into the matrix allocator.

     The affinity change added a warning to catch the case where an
     interrupt is moved on the same CPU to a different vector. This
     triggers because a condition with an empty cpumask returns an
     assignment from the allocator as the allocator uses for_each_cpu()
     without checking the cpumask for being empty. The historical
     inconsistent for_each_cpu() behaviour of ignoring the cpumask and
     unconditionally claiming that CPU0 is in the mask struck again.
     Sigh.

  plus a new entry into the MAINTAINER file for the HPE/UV platform"

* tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Deal with the sillyness of for_each_cpu() on UP
  x86/irq: Unbreak interrupt affinity setting
  x86/hotplug: Silence APIC only after all interrupts are migrated
  MAINTAINERS: Add entry for HPE Superdome Flex (UV) maintainers

Pull irq fixes from Thomas Gleixner:
 "A set of fixes for interrupt chip drivers:

   - Revert the platform driver conversion of interrupt chip drivers as
     it turned out to create more problems than it solves.

   - Fix a trivial typo in the new module helpers which made probing
     reliably fail.

   - Small fixes in the STM32 and MIPS Ingenic drivers

   - The TI firmware rework which had badly managed dependencies and had
     to wait post rc1"

* tag 'irq-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/ingenic: Leave parent IRQ unmasked on suspend
  irqchip/stm32-exti: Avoid losing interrupts due to clearing pending bits by mistake
  irqchip: Revert modular support for drivers using IRQCHIP_PLATFORM_DRIVER helperse
  irqchip: Fix probing deferal when using IRQCHIP_PLATFORM_DRIVER helpers
  arm64: dts: k3-am65: Update the RM resource types
  arm64: dts: k3-am65: ti-sci-inta/intr: Update to latest bindings
  arm64: dts: k3-j721e: ti-sci-inta/intr: Update to latest bindings
  irqchip/ti-sci-inta: Add support for INTA directly connecting to GIC
  irqchip/ti-sci-inta: Do not store TISCI device id in platform device id field
  dt-bindings: irqchip: Convert ti, sci-inta bindings to yaml
  dt-bindings: irqchip: ti, sci-inta: Update docs to support different parent.
  irqchip/ti-sci-intr: Add support for INTR being a parent to INTR
  dt-bindings: irqchip: Convert ti, sci-intr bindings to yaml
  dt-bindings: irqchip: ti, sci-intr: Update bindings to drop the usage of gic as parent
  firmware: ti_sci: Add support for getting resource with subtype
  firmware: ti_sci: Drop unused structure ti_sci_rm_type_map
  firmware: ti_sci: Drop the device id to resource type translation

Pull scheduler fix from Thomas Gleixner:
 "A single fix for the scheduler:

   - Make is_idle_task() __always_inline to prevent the compiler from
     putting it out of line into the wrong section because it's used
     inside noinstr sections"

* tag 'sched-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Use __always_inline on is_idle_task()

Pull locking fixes from Thomas Gleixner:
 "A set of fixes for lockdep, tracing and RCU:

   - Prevent recursion by using raw_cpu_* operations

   - Fixup the interrupt state in the cpu idle code to be consistent

   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections

   - Move trace_cpu_idle() into generic code so it's called before RCU
     goes idle.

   - Handle raw_local_irq* vs. local_irq* operations correctly

   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent"

* tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep,trace: Expose tracepoints
  lockdep: Only trace IRQ edges
  mips: Implement arch_irqs_disabled()
  arm64: Implement arch_irqs_disabled()
  nds32: Implement arch_irqs_disabled()
  locking/lockdep: Cleanup
  x86/entry: Remove unused THUNKs
  cpuidle: Move trace_cpu_idle() into generic code
  cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
  sched,idle,rcu: Push rcu_idle deeper into the idle path
  cpuidle: Fixup IRQ state
  lockdep: Use raw_cpu_*() for per-cpu variables

Pull cfis fix from Steve French:
 "DFS fix for referral problem when using SMB1"

* tag '5.9-rc2-smb-fix' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix check of tcon dfs in smb1

Pull powerpc fixes from Michael Ellerman:

 - Revert our removal of PROT_SAO, at least one user expressed an
   interest in using it on Power9. Instead don't allow it to be used in
   guests unless enabled explicitly at compile time.

 - A fix for a crash introduced by a recent change to FP handling.

 - Revert a change to our idle code that left Power10 with no idle
   support.

 - One minor fix for the new scv system call path to set PPR.

 - Fix a crash in our "generic" PMU if branch stack events were enabled.

 - A fix for the IMC PMU, to correctly identify host kernel samples.

 - The ADB_PMU powermac code was found to be incompatible with
   VMAP_STACK, so make them incompatible in Kconfig until the code can
   be fixed.

 - A build fix in drivers/video/fbdev/controlfb.c, and a documentation
   fix.

Thanks to Alexey Kardashevskiy, Athira Rajeev, Christophe Leroy,
Giuseppe Sacco, Madhavan Srinivasan, Milton Miller, Nicholas Piggin,
Pratik Rajesh Sampat, Randy Dunlap, Shawn Anastasio, Vaidyanathan
Srinivasan.

* tag 'powerpc-5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/32s: Disable VMAP stack which CONFIG_ADB_PMU
  Revert "powerpc/powernv/idle: Replace CPU feature check with PVR check"
  powerpc/perf: Fix reading of MSR[HV/PR] bits in trace-imc
  powerpc/perf: Fix crashes with generic_compat_pmu & BHRB
  powerpc/64s: Fix crash in load_fp_state() due to fpexc_mode
  powerpc/64s: scv entry should set PPR
  Documentation/powerpc: fix malformed table in syscall64-abi
  video: fbdev: controlfb: Fix build for COMPILE_TEST=y && PPC_PMAC=n
  selftests/powerpc: Update PROT_SAO test to skip ISA 3.1
  powerpc/64s: Disallow PROT_SAO in LPARs by default
  Revert "powerpc/64s: Remove PROT_SAO support"

Pull USB fixes from Greg KH:
 "Let's try this again...  Here are some USB fixes for 5.9-rc3.

  This differs from the previous pull request for this release in that
  the usb gadget patch now does not break some systems, and actually
  does what it was intended to do. Many thanks to Marek Szyprowski for
  quickly noticing and testing the patch from Andy Shevchenko to resolve
  this issue.

  Additionally, some more new USB quirks have been added to get some new
  devices to work properly based on user reports.

  Other than that, the patches are all here, and they contain:

   - usb gadget driver fixes

   - xhci driver fixes

   - typec fixes

   - new quirks and ids

   - fixes for USB patches that went into 5.9-rc1.

  All of these have been tested in linux-next with no reported issues"

* tag 'usb-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (33 commits)
  usb: storage: Add unusual_uas entry for Sony PSZ drives
  USB: Ignore UAS for JMicron JMS567 ATA/ATAPI Bridge
  usb: host: ohci-exynos: Fix error handling in exynos_ohci_probe()
  USB: gadget: u_f: Unbreak offset calculation in VLAs
  USB: quirks: Ignore duplicate endpoint on Sound Devices MixPre-D
  usb: typec: tcpm: Fix Fix source hard reset response for TDA 2.3.1.1 and TDA 2.3.1.2 failures
  USB: PHY: JZ4770: Fix static checker warning.
  USB: gadget: f_ncm: add bounds checks to ncm_unwrap_ntb()
  USB: gadget: u_f: add overflow checks to VLA macros
  xhci: Always restore EP_SOFT_CLEAR_TOGGLE even if ep reset failed
  xhci: Do warm-reset when both CAS and XDEV_RESUME are set
  usb: host: xhci: fix ep context print mismatch in debugfs
  usb: uas: Add quirk for PNY Pro Elite
  tools: usb: move to tools buildsystem
  USB: Fix device driver race
  USB: Also match device drivers using the ->match vfunc
  usb: host: xhci-tegra: fix tegra_xusb_get_phy()
  usb: host: xhci-tegra: otg usb2/usb3 port init
  usb: hcd: Fix use after free in usb_hcd_pci_remove()
  usb: typec: ucsi: Hold con->lock for the entire duration of ucsi_register_port()
  ...

Pull EDAC fix from Borislav Petkov:
 "A fix to properly clear ghes_edac driver state on driver remove so
  that a subsequent load can probe the system properly (Shiju Jose)"

* tag 'edac_urgent_for_v5.9_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/ghes: Fix NULL pointer dereference in ghes_edac_register()

Pull dma-mapping fix from Christoph Hellwig:
 "Fix a possibly uninitialized variable (Dan Carpenter)"

* tag 'dma-mapping-5.9-2' of git://git.infradead.org/users/hch/dma-mapping:
  dma-pool: Fix an uninitialized variable bug in atomic_pool_expand()

Most of the CPU mask operations behave the same way, but for_each_cpu() and
it's variants ignore the cpumask argument and claim that CPU0 is always in
the mask. This is historical, inconsistent and annoying behaviour.

The matrix allocator uses for_each_cpu() and can be called on UP with an
empty cpumask. The calling code does not expect that this succeeds but
until commit e027ffff ("x86/irq: Unbreak interrupt affinity setting")
this went unnoticed. That commit added a WARN_ON() to catch cases which
move an interrupt from one vector to another on the same CPU. The warning
triggers on UP.

Add a check for the cpumask being empty to prevent this.

Fixes: 2f75d9e1 ("genirq: Implement bitmap matrix allocator")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org

Merge tag 'fallthrough-fixes-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fallthrough fixes from Gustavo A. R. Silva:
 "Fix some minor issues introduced by the recent treewide fallthrough
  conversions:

   - Fix identation issue

   - Fix erroneous fallthrough annotation

   - Remove unnecessary fallthrough annotation

   - Fix code comment changed by fallthrough conversion"

* tag 'fallthrough-fixes-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  arm64/cpuinfo: Remove unnecessary fallthrough annotation
  media: dib0700: Fix identation issue in dib8096_set_param_override()
  afs: Remove erroneous fallthough annotation
  iio: dpot-dac: fix code comment in dpot_dac_read_raw()

Commit ef91bb19 ("kernel.h: Silence sparse warning in
lower_32_bits") caused new warnings to show in the fsldma driver, but
that commit was not to blame: it only exposed some very incorrect code
that tried to take the low 32 bits of an address.

That made no sense for multiple reasons, the most notable one being that
that code was intentionally limited to only 32-bit ppc builds, so "only
low 32 bits of an address" was completely nonsensical.  There were no
high bits to mask off to begin with.

But even more importantly fropm a correctness standpoint, turning the
address into an integer then caused the subsequent address arithmetic to
be completely wrong too, and the "+1" actually incremented the address
by one, rather than by four.

Which again was incorrect, since the code was reading two 32-bit values
and trying to make a 64-bit end result of it all.  Surprisingly, the
iowrite64() did not suffer from the same odd and incorrect model.

This code has never worked, but it's questionable whether anybody cared:
of the two users that actually read the 64-bit value (by way of some C
preprocessor hackery and eventually the 'get_cdar()' inline function),
one of them explicitly ignored the value, and the other one might just
happen to work despite the incorrect value being read.

This patch at least makes it not fail the build any more, and makes the
logic superficially sane.  Whether it makes any difference to the code
_working_ or not shall remain a mystery.
Compile-tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull i2c fixes from Wolfram Sang:
 "A core fix for ACPI matching and two driver bugfixes"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: iproc: Fix shifting 31 bits
  i2c: rcar: in slave mode, clear NACK earlier
  i2c: acpi: Remove dead code, i.e. i2c_acpi_match_device()
  i2c: core: Don't fail PRP0001 enumeration when no ID table exist

Pull s390 fixes from Vasily Gorbik:

 - Disable preemption trace in percpu macros since the lockdep code
   itself uses percpu variables now and it causes recursions.

 - Fix kernel space 4-level paging broken by recent vmem rework.

* tag 's390-5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/vmem: fix vmem_add_range for 4-level paging
  s390: don't trace preemption in percpu macros

Pull xen fixes from Juergen Gross:
 "Two fixes for Xen: one needed for ongoing work to support virtio with
  Xen, and one for a corner case in IRQ handling with Xen"

* tag 'for-linus-5.9-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  arm/xen: Add misuse warning to virt_to_gfn
  xen/xenbus: Fix granting of vmalloc'd memory
  XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.

Merge tag 'hwmon-for-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Fix tempeerature scale in gsc-hwmon driver

 - Fix divide by 0 error in nct7904 driver

 - Drop non-existing attribute from pmbus/isl68137 driver

 - Fix status check in applesmc driver

* tag 'hwmon-for-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (gsc-hwmon) Scale temperature to millidegrees
  hwmon: (applesmc) check status earlier.
  hwmon: (nct7904) Correct divide by 0
  hwmon: (pmbus/isl68137) remove READ_TEMPERATURE_1 telemetry for RAA228228

Pull NVMe fixes from Sagi:

"- instance leak and io boundary fixes from Keith
 - fc locking fix from Christophe
 - various tcp/rdma reset during traffic fixes from Me
 - pci use-after-free fix from Tong
 - tcp target null deref fix from Ziye"

* 'nvme-5.9-rc' of git://git.infradead.org/nvme:
  nvme-pci: cancel nvme device request before disabling
  nvme: only use power of two io boundaries
  nvme: fix controller instance leak
  nvmet-fc: Fix a missed _irqsave version of spin_lock in 'nvmet_fc_fod_op_done()'
  nvme: Fix NULL dereference for pci nvme controllers
  nvme-rdma: fix reset hang if controller died in the middle of a reset
  nvme-rdma: fix timeout handler
  nvme-rdma: serialize controller teardown sequences
  nvme-tcp: fix reset hang if controller died in the middle of a reset
  nvme-tcp: fix timeout handler
  nvme-tcp: serialize controller teardown sequences
  nvme: have nvme_wait_freeze_timeout return if it timed out
  nvme-fabrics: don't check state NVME_CTRL_NEW for request acceptance
  nvmet-tcp: Fix NULL dereference when a connect data comes in h2cdata pdu

This patch addresses an irq free warning and null pointer dereference
error problem when nvme devices got timeout error during initialization.
This problem happens when nvme_timeout() function is called while
nvme_reset_work() is still in execution. This patch fixed the problem by
setting flag of the problematic request to NVME_REQ_CANCELLED before
calling nvme_dev_disable() to make sure __nvme_submit_sync_cmd() returns
an error code and let nvme_submit_sync_cmd() fail gracefully.
The following is console output.

[   62.472097] nvme nvme0: I/O 13 QID 0 timeout, disable controller
[   62.488796] nvme nvme0: could not set timestamp (881)
[   62.494888] ------------[ cut here ]------------
[   62.495142] Trying to free already-free IRQ 11
[   62.495366] WARNING: CPU: 0 PID: 7 at kernel/irq/manage.c:1751 free_irq+0x1f7/0x370
[   62.495742] Modules linked in:
[   62.495902] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0+ #8
[   62.496206] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-p4
[   62.496772] Workqueue: nvme-reset-wq nvme_reset_work
[   62.497019] RIP: 0010:free_irq+0x1f7/0x370
[   62.497223] Code: e8 ce 49 11 00 48 83 c4 08 4c 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 44 89 f6 48 c70
[   62.498133] RSP: 0000:ffffa96800043d40 EFLAGS: 00010086
[   62.498391] RAX: 0000000000000000 RBX: ffff9b87fc458400 RCX: 0000000000000000
[   62.498741] RDX: 0000000000000001 RSI: 0000000000000096 RDI: ffffffff9693d72c
[   62.499091] RBP: ffff9b87fd4c8f60 R08: ffffa96800043bfd R09: 0000000000000163
[   62.499440] R10: ffffa96800043bf8 R11: ffffa96800043bfd R12: ffff9b87fd4c8e00
[   62.499790] R13: ffff9b87fd4c8ea4 R14: 000000000000000b R15: ffff9b87fd76b000
[   62.500140] FS:  0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000
[   62.500534] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   62.500816] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0
[   62.501165] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   62.501515] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   62.501864] Call Trace:
[   62.501993]  pci_free_irq+0x13/0x20
[   62.502167]  nvme_reset_work+0x5d0/0x12a0
[   62.502369]  ? update_load_avg+0x59/0x580
[   62.502569]  ? ttwu_queue_wakelist+0xa8/0xc0
[   62.502780]  ? try_to_wake_up+0x1a2/0x450
[   62.502979]  process_one_work+0x1d2/0x390
[   62.503179]  worker_thread+0x45/0x3b0
[   62.503361]  ? process_one_work+0x390/0x390
[   62.503568]  kthread+0xf9/0x130
[   62.503726]  ? kthread_park+0x80/0x80
[   62.503911]  ret_from_fork+0x22/0x30
[   62.504090] ---[ end trace de9ed4a70f8d71e2 ]---
[  123.912275] nvme nvme0: I/O 12 QID 0 timeout, disable controller
[  123.914670] nvme nvme0: 1/0/0 default/read/poll queues
[  123.916310] BUG: kernel NULL pointer dereference, address: 0000000000000000
[  123.917469] #PF: supervisor write access in kernel mode
[  123.917725] #PF: error_code(0x0002) - not-present page
[  123.917976] PGD 0 P4D 0
[  123.918109] Oops: 0002 [#1] SMP PTI
[  123.918283] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G        W         5.8.0+ #8
[  123.918650] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-p4
[  123.919219] Workqueue: nvme-reset-wq nvme_reset_work
[  123.919469] RIP: 0010:__blk_mq_alloc_map_and_request+0x21/0x80
[  123.919757] Code: 66 0f 1f 84 00 00 00 00 00 41 55 41 54 55 48 63 ee 53 48 8b 47 68 89 ee 48 89 fb 8b4
[  123.920657] RSP: 0000:ffffa96800043d40 EFLAGS: 00010286
[  123.920912] RAX: ffff9b87fc4fee40 RBX: ffff9b87fc8cb008 RCX: 0000000000000000
[  123.921258] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9b87fc618000
[  123.921602] RBP: 0000000000000000 R08: ffff9b87fdc2c4a0 R09: ffff9b87fc616000
[  123.921949] R10: 0000000000000000 R11: ffff9b87fffd1500 R12: 0000000000000000
[  123.922295] R13: 0000000000000000 R14: ffff9b87fc8cb200 R15: ffff9b87fc8cb000
[  123.922641] FS:  0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000
[  123.923032] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  123.923312] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0
[  123.923660] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  123.924007] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  123.924353] Call Trace:
[  123.924479]  blk_mq_alloc_tag_set+0x137/0x2a0
[  123.924694]  nvme_reset_work+0xed6/0x12a0
[  123.924898]  process_one_work+0x1d2/0x390
[  123.925099]  worker_thread+0x45/0x3b0
[  123.925280]  ? process_one_work+0x390/0x390
[  123.925486]  kthread+0xf9/0x130
[  123.925642]  ? kthread_park+0x80/0x80
[  123.925825]  ret_from_fork+0x22/0x30
[  123.926004] Modules linked in:
[  123.926158] CR2: 0000000000000000
[  123.926322] ---[ end trace de9ed4a70f8d71e3 ]---
[  123.926549] RIP: 0010:__blk_mq_alloc_map_and_request+0x21/0x80
[  123.926832] Code: 66 0f 1f 84 00 00 00 00 00 41 55 41 54 55 48 63 ee 53 48 8b 47 68 89 ee 48 89 fb 8b4
[  123.927734] RSP: 0000:ffffa96800043d40 EFLAGS: 00010286
[  123.927989] RAX: ffff9b87fc4fee40 RBX: ffff9b87fc8cb008 RCX: 0000000000000000
[  123.928336] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9b87fc618000
[  123.928679] RBP: 0000000000000000 R08: ffff9b87fdc2c4a0 R09: ffff9b87fc616000
[  123.929025] R10: 0000000000000000 R11: ffff9b87fffd1500 R12: 0000000000000000
[  123.929370] R13: 0000000000000000 R14: ffff9b87fc8cb200 R15: ffff9b87fc8cb000
[  123.929715] FS:  0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000
[  123.930106] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  123.930384] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0
[  123.930731] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  123.931077] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Co-developed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

The kernel requires a power of two for boundaries because that's the
only way it can efficiently split commands that cross them. A
controller, however, may report a non-power of two boundary.

The driver had been rounding the controller's value to one the kernel
can use, but splitting on the wrong boundary provides no benefit on the
device side, and incurs additional submission overhead from non-optimal
splits.

Don't provide any boundary hint if the controller's value can't be used
and log a warning when first scanning a disk's unreported IO boundary.
Since the chunk sector logic has grown, move it to a separate function.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

If the driver has to unbind from the controller for an early failure
before the subsystem has been set up, there won't be a subsystem holding
the controller's instance, so the controller needs to free its own
instance in this case.

Fixes: 733e4b69 ("nvme: Assign subsys instance from first ctrl")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

The way 'spin_lock()' and 'spin_lock_irqsave()' are used is not consistent
in this function.

Use 'spin_lock_irqsave()' also here, as there is no guarantee that
interruptions are disabled at that point, according to surrounding code.

Fixes: a97ec51b ("nvmet_fc: Rework target side abort handling")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

PCIe controllers do not have fabric opts, verify they exist before
showing ctrl_loss_tmo or reconnect_delay attributes.

Fixes: 764075fd ("nvme: expose reconnect_delay and ctrl_loss_tmo via sysfs")
Reported-by: Tobias Markus <tobias@markus-regensburg.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

If the controller becomes unresponsive in the middle of a reset, we
will hang because we are waiting for the freeze to complete, but that
cannot happen since we have commands that are inflight holding the
q_usage_counter, and we can't blindly fail requests that times out.

So give a timeout and if we cannot wait for queue freeze before
unfreezing, fail and have the error handling take care how to
proceed (either schedule a reconnect of remove the controller).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

When a request times out in a LIVE state, we simply trigger error
recovery and let the error recovery handle the request cancellation,
however when a request times out in a non LIVE state, we make sure to
complete it immediately as it might block controller setup or teardown
and prevent forward progress.

However tearing down the entire set of I/O and admin queues causes
freeze/unfreeze imbalance (q->mq_freeze_depth) because and is really
an overkill to what we actually need, which is to just fence controller
teardown that may be running, stop the queue, and cancel the request if
it is not already completed.

Now that we have the controller teardown_lock, we can safely serialize
request cancellation. This addresses a hang caused by calling extra
queue freeze on controller namespaces, causing unfreeze to not complete
correctly.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

In the timeout handler we may need to complete a request because the
request that timed out may be an I/O that is a part of a serial sequence
of controller teardown or initialization. In order to complete the
request, we need to fence any other context that may compete with us
and complete the request that is timing out.

In this case, we could have a potential double completion in case
a hard-irq or a different competing context triggered error recovery
and is running inflight request cancellation concurrently with the
timeout handler.

Protect using a ctrl teardown_lock to serialize contexts that may
complete a cancelled request due to error recovery or a reset.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

If the controller becomes unresponsive in the middle of a reset, we will
hang because we are waiting for the freeze to complete, but that cannot
happen since we have commands that are inflight holding the
q_usage_counter, and we can't blindly fail requests that times out.

So give a timeout and if we cannot wait for queue freeze before
unfreezing, fail and have the error handling take care how to proceed
(either schedule a reconnect of remove the controller).
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

When a request times out in a LIVE state, we simply trigger error
recovery and let the error recovery handle the request cancellation,
however when a request times out in a non LIVE state, we make sure to
complete it immediately as it might block controller setup or teardown
and prevent forward progress.

However tearing down the entire set of I/O and admin queues causes
freeze/unfreeze imbalance (q->mq_freeze_depth) because and is really
an overkill to what we actually need, which is to just fence controller
teardown that may be running, stop the queue, and cancel the request if
it is not already completed.

Now that we have the controller teardown_lock, we can safely serialize
request cancellation. This addresses a hang caused by calling extra
queue freeze on controller namespaces, causing unfreeze to not complete
correctly.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

In the timeout handler we may need to complete a request because the
request that timed out may be an I/O that is a part of a serial sequence
of controller teardown or initialization. In order to complete the
request, we need to fence any other context that may compete with us
and complete the request that is timing out.

In this case, we could have a potential double completion in case
a hard-irq or a different competing context triggered error recovery
and is running inflight request cancellation concurrently with the
timeout handler.

Protect using a ctrl teardown_lock to serialize contexts that may
complete a cancelled request due to error recovery or a reset.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

Users can detect if the wait has completed or not and take appropriate
actions based on this information (e.g. weather to continue
initialization or rather fail and schedule another initialization
attempt).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>