The dtcm_end and itcm_end are not exported or used
elsewhere, so make them static to remove the following
sparse warnign:

arch/arm/kernel/tcm.c:33:5: warning: symbol 'dtcm_end' was not declared. Should it be static?
arch/arm/kernel/tcm.c:34:5: warning: symbol 'itcm_end' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

iomap.c needs <asm/vga.h> for the definition vga_base
to avoid the following warning:

arch/arm/mm/iomap.c:13:15: warning: symbol 'vga_base' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The rate pointer in parse_dt_topology is a pointer to a
__be32, not a u32. This fixes the following sparse warning:

arch/arm/kernel/topology.c:128:43: warning: incorrect type in argument 1 (different base types)
arch/arm/kernel/topology.c:128:43:    expected restricted __be32 const [usertype] *p
arch/arm/kernel/topology.c:128:43:    got unsigned int const [usertype] *[assigned] rate
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The get_signal_page() function is defined in signal.c and used in
process.c but there is no shared definition. Add one in signal.h to
silence the following warning:

arch/arm/kernel/signal.c:683:13: warning: symbol 'get_signal_page' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The psci_cpu_{disable,die,kill} functions are not
exported, so make them static to avoid the following
warnings:

arch/arm/kernel/psci_smp.c:54:5: warning: symbol 'psci_cpu_disable' was not declared. Should it be static?
arch/arm/kernel/psci_smp.c:67:6: warning: symbol 'psci_cpu_die' was not declared. Should it be static?
arch/arm/kernel/psci_smp.c:79:5: warning: symbol 'psci_cpu_kill' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The definitions of set_kernel_text_rw() and
set_kernel_text_ro() are in <asm/set_memory.h>
but this is not included in init.c which defines
these. Silence the following warnings by including
the <asm/set_memory.h> header.

arch/arm/mm/init.c:669:6: warning: symbol 'set_kernel_text_rw' was not declared. Should it be static?
arch/arm/mm/init.c:678:6: warning: symbol 'set_kernel_text_ro' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The set_section_perms() is not defined outside of the
init.c file, so make it static to avoid the following
warning:

arch/arm/mm/init.c:596:6: warning: symbol 'set_section_perms' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

There are some sparse warnings about type conversion in
the atags_to_fdt.c code, due to __be32 and __be64, so
fix the following:

- Change _be32 and __be64 where appropriate
- Change setprop() to take a 'void *'
- Change incorrect fdt32_to_cpu() on FDT_MAGIC

Fixes the following sparse warnings:

arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:66:29: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:141:34: warning: cast to restricted __be32
arch/arm/boot/compressed/atags_to_fdt.c:182:60: warning: incorrect type in assignment (different base types)
arch/arm/boot/compressed/atags_to_fdt.c:182:60:    expected unsigned long long [usertype]
arch/arm/boot/compressed/atags_to_fdt.c:182:60:    got restricted __be64 [usertype]
arch/arm/boot/compressed/atags_to_fdt.c:184:60: warning: incorrect type in assignment (different base types)
arch/arm/boot/compressed/atags_to_fdt.c:184:60:    expected unsigned long long [usertype]
arch/arm/boot/compressed/atags_to_fdt.c:184:60:    got restricted __be64 [usertype]
arch/arm/boot/compressed/atags_to_fdt.c:187:62: warning: incorrect type in assignment (different base types)
arch/arm/boot/compressed/atags_to_fdt.c:187:62:    expected unsigned int
arch/arm/boot/compressed/atags_to_fdt.c:187:62:    got restricted __be32 [usertype]
arch/arm/boot/compressed/atags_to_fdt.c:189:62: warning: incorrect type in assignment (different base types)
arch/arm/boot/compressed/atags_to_fdt.c:189:62:    expected unsigned int
arch/arm/boot/compressed/atags_to_fdt.c:189:62:    got restricted __be32 [usertype]
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The arch_timer_arch_init is defined in <asm/arch_timer.h> so include
that to fix the following sparse error:

arch/arm/kernel/arch_timer.c:31:12: warning: symbol 'arch_timer_arch_init' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Move the pcibios_report_status to <asm/pci.h> include to remove the
following sparse warning and to remove the extra definition in the
footbrdige dc21285.c driver:

arch/arm/kernel/bios32.c:59:6: warning: symbol 'pcibios_report_status' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The module_frob_arch_sections function is missing the header declaration
which is in <linux/moduleloader.h> so include that to fix the following
sparse warning:

arch/arm/kernel/module-plts.c:188:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Fixup the following sparse warnings by making the functions and structures
static.

arch/arm/mm/dma-mapping.c:1562:6: warning: symbol '__arm_iommu_free_attrs' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1586:6: warning: symbol 'arm_iommu_free_attrs' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1592:6: warning: symbol 'arm_coherent_iommu_free_attrs' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1716:5: warning: symbol 'arm_coherent_iommu_map_sg' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1734:5: warning: symbol 'arm_iommu_map_sg' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1767:6: warning: symbol 'arm_coherent_iommu_unmap_sg' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1784:6: warning: symbol 'arm_iommu_unmap_sg' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1798:6: warning: symbol 'arm_iommu_sync_sg_for_cpu' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:1816:6: warning: symbol 'arm_iommu_sync_sg_for_device' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:2018:26: warning: symbol 'iommu_ops' was not declared. Should it be static?
arch/arm/mm/dma-mapping.c:2040:26: warning: symbol 'iommu_coherent_ops' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Avoid calling __pfn_to_phys twice.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for the VMWare guest support:

   - Unbreak VMWare platform detection which got wreckaged by converting
     an integer constant to a string constant.

   - Fix the clang build of the VMWAre hypercall by explicitely
     specifying the ouput register for INL instead of using the short
     form"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/vmware: Fix platform detection VMWARE_PORT macro
  x86/cpu/vmware: Use the full form of INL in VMWARE_HYPERCALL, for clang/llvm

Pull timer fixes from Thomas Gleixner:
 "A small set of fixes for time(keeping):

   - Add a missing include to prevent compiler warnings.

   - Make the VDSO implementation of clock_getres() POSIX compliant
     again. A recent change dropped the NULL pointer guard which is
     required as NULL is a valid pointer value for this function.

   - Fix two function documentation typos"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Fix two trivial comments
  timers/sched_clock: Include local timekeeping.h for missing declarations
  lib/vdso: Make clock_getres() POSIX compliant again

Pull perf fixes from Thomas Gleixner:
 "A set of perf fixes:

  kernel:

   - Unbreak the tracking of auxiliary buffer allocations which got
     imbalanced causing recource limit failures.

   - Fix the fallout of splitting of ToPA entries which missed to shift
     the base entry PA correctly.

   - Use the correct context to lookup the AUX event when unmapping the
     associated AUX buffer so the event can be stopped and the buffer
     reference dropped.

  tools:

   - Fix buildiid-cache mode setting in copyfile_mode_ns() when copying
     /proc/kcore

   - Fix freeing id arrays in the event list so the correct event is
     closed.

   - Sync sched.h anc kvm.h headers with the kernel sources.

   - Link jvmti against tools/lib/ctype.o to have weak strlcpy().

   - Fix multiple memory and file descriptor leaks, found by coverity in
     perf annotate.

   - Fix leaks in error handling paths in 'perf c2c', 'perf kmem', found
     by a static analysis tool"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/aux: Fix AUX output stopping
  perf/aux: Fix tracking of auxiliary trace buffer allocation
  perf/x86/intel/pt: Fix base for single entry topa
  perf kmem: Fix memory leak in compact_gfp_flags()
  tools headers UAPI: Sync sched.h with the kernel
  tools headers kvm: Sync kvm.h headers with the kernel sources
  tools headers kvm: Sync kvm headers with the kernel sources
  tools headers kvm: Sync kvm headers with the kernel sources
  perf c2c: Fix memory leak in build_cl_output()
  perf tools: Fix mode setting in copyfile_mode_ns()
  perf annotate: Fix multiple memory and file descriptor leaks
  perf tools: Fix resource leak of closedir() on the error paths
  perf evlist: Fix fix for freed id arrays
  perf jvmti: Link against tools/lib/ctype.h to have weak strlcpy()

Pull irq fixes from Thomas Gleixner:
 "Two fixes for interrupt controller drivers:

   - Skip IRQ_M_EXT entries in the device tree when initializing the
     RISCV PLIC controller to avoid a double init attempt.

   - Use the correct ITS list when issuing the VMOVP synchronization
     command so the operation works only on the ITS instances which are
     associated to a VM"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/sifive-plic: Skip contexts except supervisor in plic_init()
  irqchip/gic-v3-its: Use the exact ITSList for VMOVP

Pull cifs fixes from Steve French:
 "Seven cifs/smb3 fixes, including three for stable"

* tag '5.4-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Fix cifsInodeInfo lock_sem deadlock when reconnect occurs
  CIFS: Fix use after free of file info structures
  CIFS: Fix retry mid list corruption on reconnects
  cifs: Fix missed free operations
  CIFS: avoid using MID 0xFFFF
  cifs: clarify comment about timestamp granularity for old servers
  cifs: Handle -EINPROGRESS only when noblockcnt is set

Pull RISC-V fixes from Paul Walmsley:
 "Several minor fixes and cleanups for v5.4-rc5:

   - Three build fixes for various SPARSEMEM-related kernel
     configurations

   - Two cleanup patches for the kernel bug and breakpoint trap handler
     code"

* tag 'riscv/for-v5.4-rc5-b' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: cleanup do_trap_break
  riscv: cleanup <asm/bug.h>
  riscv: Fix undefined reference to vmemmap_populate_basepages
  riscv: Fix implicit declaration of 'page_to_section'
  riscv: fix fs/proc/kcore.c compilation with sparsemem enabled

Pull MIPS fixes from Paul Burton:
 "A few MIPS fixes:

   - Fix VDSO time-related function behavior for systems where we need
     to fall back to syscalls, but were instead returning bogus results.

   - A fix to TLB exception handlers for Cavium Octeon systems where
     they would inadvertently clobber the $1/$at register.

   - A build fix for bcm63xx configurations.

   - Switch to using my @kernel.org email address"

* tag 'mips_fixes_5.4_3' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: tlbex: Fix build_restore_pagemask KScratch restore
  MIPS: bmips: mark exception vectors as char arrays
  mips: vdso: Fix __arch_get_hw_counter()
  MAINTAINERS: Use @kernel.org address for Paul Burton

Pull tty/serial driver fix from Greg KH:
 "Here is a single tty/serial driver fix for 5.4-rc5 that resolves a
  reported issue.

  It has been in linux-next for a while with no problems"

* tag 'tty-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  8250-men-mcb: fix error checking when get_num_ports returns -ENODEV

Pull staging driver fix from Greg KH:
 "Here is a single staging driver fix, for the wlan-ng driver, that
  resolves a reported issue.

  It is been in linux-next for a while with no reported issues"

* tag 'staging-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: wlan-ng: fix exit return when sme->key_idx >= NUM_WEPKEYS

Pull driver core fix from Greg KH:
 "Here is a single sysfs fix for 5.4-rc5.

  It resolves an error if you actually try to use the __BIN_ATTR_WO()
  macro, seems I never tested it properly before :(

  This has been in linux-next for a while with no reported issues"

* tag 'driver-core-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  sysfs: Fixes __BIN_ATTR_WO() macro

Pull binder fix from Greg KH:
 "This is a single binder fix to resolve a reported issue by Jann. It's
  been in linux-next for a while with no reported issues"

* tag 'char-misc-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  binder: Don't modify VMA bounds in ->mmap handler

Pull USB fixes from Greg KH:
 "Here are a number of small USB driver fixes for 5.4-rc5.

  More "fun" with some of the misc USB drivers as found by syzbot, and
  there are a number of other small bugfixes in here for reported
  issues.

  All have been in linux-next for a while with no reported issues"

* tag 'usb-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: cdns3: Error out if USB_DR_MODE_UNKNOWN in cdns3_core_init_role()
  USB: ldusb: fix read info leaks
  USB: serial: ti_usb_3410_5052: clean up serial data access
  USB: serial: ti_usb_3410_5052: fix port-close races
  USB: usblp: fix use-after-free on disconnect
  usb: udc: lpc32xx: fix bad bit shift operation
  usb: cdns3: Fix dequeue implementation.
  USB: legousbtower: fix a signedness bug in tower_probe()
  USB: legousbtower: fix memleak on disconnect
  USB: ldusb: fix memleak on disconnect

Pull i2c fixes from Wolfram Sang:
 "A few driver fixes for the I2C subsystem"

* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: stm32f7: remove warning when compiling with W=1
  i2c: stm32f7: fix a race in slave mode with arbitration loss irq
  i2c: stm32f7: fix first byte to send in slave mode
  i2c: mt65xx: fix NULL ptr dereference
  i2c: aspeed: fix master pending state handling

Pull block and io_uring fixes from Jens Axboe:
 "A bit bigger than usual at this point in time, mostly due to some good
  bug hunting work by Pavel that resulted in three io_uring fixes from
  him and two from me. Anyway, this pull request contains:

   - Revert of the submit-and-wait optimization for io_uring, it can't
     always be done safely. It depends on commands always making
     progress on their own, which isn't necessarily the case outside of
     strict file IO. (me)

   - Series of two patches from me and three from Pavel, fixing issues
     with shared data and sequencing for io_uring.

   - Lastly, two timeout sequence fixes for io_uring (zhangyi)

   - Two nbd patches fixing races (Josef)

   - libahci regulator_get_optional() fix (Mark)"

* tag 'for-linus-2019-10-26' of git://git.kernel.dk/linux-block:
  nbd: verify socket is supported during setup
  ata: libahci_platform: Fix regulator_get_optional() misuse
  nbd: handle racing with error'ed out commands
  nbd: protect cmd->status with cmd->lock
  io_uring: fix bad inflight accounting for SETUP_IOPOLL|SETUP_SQTHREAD
  io_uring: used cached copies of sq->dropped and cq->overflow
  io_uring: Fix race for sqes with userspace
  io_uring: Fix broken links with offloading
  io_uring: Fix corrupted user_data
  io_uring: correct timeout req sequence when inserting a new entry
  io_uring : correct timeout req sequence when waiting timeout
  io_uring: revert "io_uring: optimize submit_and_wait API"

Pull s390 fixes from Vasily Gorbik:

 - Add R_390_GLOB_DAT relocation type support. This fixes boot problem
   on linux-next.

 - Fix memory leak in zcrypt

* tag 's390-5.4-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/kaslr: add support for R_390_GLOB_DAT relocation type
  s390/zcrypt: fix memleak at release

Pull xen fixlet from Juergen Gross:
 "Just one patch for issuing a deprecation warning for 32-bit Xen pv
  guests"

* tag 'for-linus-5.4-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: issue deprecation warning for 32-bit pv guest

Pull dma-mapping fix from Christoph Hellwig:
 "Fix a regression in the intel-iommu get_required_mask conversion
  (Arvind Sankar)"

* tag 'dma-mapping-5.4-2' of git://git.infradead.org/users/hch/dma-mapping:
  iommu/vt-d: Return the correct dma mask when we are bypassing the IOMMU

Pull dax fix from Dan Williams:
 "Fix a performance regression that followed from a fix to the
  conversion of the fsdax implementation to the xarray. v5.3 users
  report that they stop seeing huge page mappings on an application +
  filesystem layout that was seeing huge pages previously on v5.2"

* tag 'dax-fix-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  fs/dax: Fix pmd vs pte conflict detection

Pull SCSI fixes from James Bottomley:
 "Nine changes, eight to drivers (qla2xxx, hpsa, lpfc, alua, ch,
  53c710[x2], target) and one core change that tries to close a race
  between sysfs delete and module removal"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: lpfc: remove left-over BUILD_NVME defines
  scsi: core: try to get module before removing device
  scsi: hpsa: add missing hunks in reset-patch
  scsi: target: core: Do not overwrite CDB byte 1
  scsi: ch: Make it possible to open a ch device multiple times again
  scsi: fix kconfig dependency warning related to 53C700_LE_ON_BE
  scsi: sni_53c710: fix compilation error
  scsi: scsi_dh_alua: handle RTPG sense code correctly during state transitions
  scsi: qla2xxx: fix a potential NULL pointer dereference

If we always compile the get_break_insn_length inline function we can
remove the ifdefs and let dead code elimination take care of the warn
branch that is now unreadable because the report_bug stub always
returns BUG_TRAP_TYPE_BUG.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

Pull input fix from Dmitry Torokhov:
 "A fix for st1232 driver to properly report coordinates for 2nd and
  subsequent fingers when more than one is on the surface"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: st1232 - fix reporting multitouch coordinates

nbd requires socket families to support the shutdown method so the nbd
recv workqueue can be woken up from its sock_recvmsg call. If the socket
does not support the callout we will leave recv works running or get hangs
later when the device or module is removed.

This adds a check during socket connection/reconnection to make sure the
socket being passed in supports the needed callout.

Reported-by: syzbot+24c12fa8d218ed26011a@syzkaller.appspotmail.com
Fixes: e9e006f5 ("nbd: fix max number of supported devs")
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This driver is using regulator_get_optional() to handle all the supplies
that it handles, and only ever enables and disables all supplies en masse
without ever doing any other configuration of the device to handle missing
power. These are clear signs that the API is being misused - it should only
be used for supplies that may be physically absent from the system and in
these cases the hardware usually needs different configuration if the
supply is missing. Instead use normal regualtor_get(), if the supply is
not described in DT then the framework will substitute a dummy regulator in
so no special handling is needed by the consumer driver.

In the case of the PHY regulator the handling in the driver is a hack to
deal with integrated PHYs; the supplies are only optional in the sense
that that there's some confusion in the code about where they're bound to.
From a code point of view they function exactly as normal supplies so can
be treated as such. It'd probably be better to model this by instantiating
a PHY object for integrated PHYs.
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We hit the following warning in production

print_req_error: I/O error, dev nbd0, sector 7213934408 flags 80700
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 25 PID: 32407 at lib/refcount.c:190 refcount_sub_and_test_checked+0x53/0x60
Workqueue: knbd-recv recv_work [nbd]
RIP: 0010:refcount_sub_and_test_checked+0x53/0x60
Call Trace:
 blk_mq_free_request+0xb7/0xf0
 blk_mq_complete_request+0x62/0xf0
 recv_work+0x29/0xa1 [nbd]
 process_one_work+0x1f5/0x3f0
 worker_thread+0x2d/0x3d0
 ? rescuer_thread+0x340/0x340
 kthread+0x111/0x130
 ? kthread_create_on_node+0x60/0x60
 ret_from_fork+0x1f/0x30
---[ end trace b079c3c67f98bb7c ]---

This was preceded by us timing out everything and shutting down the
sockets for the device.  The problem is we had a request in the queue at
the same time, so we completed the request twice.  This can actually
happen in a lot of cases, we fail to get a ref on our config, we only
have one connection and just error out the command, etc.

Fix this by checking cmd->status in nbd_read_stat.  We only change this
under the cmd->lock, so we are safe to check this here and see if we've
already error'ed this command out, which would indicate that we've
completed it as well.
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We already do this for the most part, except in timeout and clear_req.
For the timeout case we take the lock after we grab a ref on the config,
but that isn't really necessary because we're safe to touch the cmd at
this point, so just move the order around.

For the clear_req cause this is initiated by the user, so again is safe.
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull modules fixes from Jessica Yu:

 - Revert __ksymtab_$namespace.$symbol naming scheme back to
   __ksymtab_$symbol, as it was causing issues with depmod.

   Instead, have modpost extract a symbol's namespace from __kstrtabns
   and __ksymtab_strings.

 - Fix `make nsdeps` for out of tree kernel builds (make O=...) caused
   by unescaped '/'.

   Use a different sed delimiter to avoid this problem.

* tag 'modules-for-v5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  scripts/nsdeps: use alternative sed delimiter
  symbol namespaces: revert to previous __ksymtab name scheme
  modpost: make updating the symbol namespace explicit
  modpost: delegate updating namespaces to separate function