When malloc() fails, there is not much userspace programs can do.
xmalloc() is useful to bail out on a memory allocation failure.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When malloc() or realloc() fails, there is not much userspace programs
can do. xmalloc() and xrealloc() are useful to bail out on a memory
allocation failure.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

I think x*alloc() functions are cleaner.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

These functions will be useful for other host programs.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

P_SYMBOL is a pseudo property that was previously used for data linking
purposes.

It is no longer used except for debug prints. Remove it.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

I believe its last usage was in the following code:

    if (prop == NULL)
            prop = stack->sym->prop;

This code was previously used to print the file name and line number of
associated symbols in sym_check_print_recursive(), which was removed by
commit 9d0d2660 ("kconfig: recursive checks drop file/lineno").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Since commit ca4c74ba ("kconfig: remove P_CHOICE property"),
menu_finalize() no longer calls menu_add_symbol(). No function
references cur_filename or cur_lineno after yyparse().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

This reverts the following commits:

 - 236dec05 ("kconfig: tinyconfig: provide whole choice blocks to
   avoid warnings")

 - b0f26972 ("x86/config: Fix warning for 'make ARCH=x86_64
   tinyconfig'")

Since commit f79dc03f ("kconfig: refactor choice value calculation"),
it is no longer necessary to disable the remaining options in choice
blocks.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

Parallel execution is supported by GNU Make:

  $ make -j<N> modules_install

It is questionable to enable multithreading within each zstd process
by default.

If you still want to do it, you can use the environment variable:

  $ ZSTD_NBTHREADS=<N> make modules_install
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

Commit 3f1b0e1f (".gitignore update") added *.orig and *.rej
patterns to .gitignore in v2.6.23. The commit message didn't give a
rationale. Later on, commit 1f5d3a6b ("Remove *.rej pattern from
.gitignore") removed the *.rej pattern in v2.6.26, on the rationale that
*.rej files indicated something went really wrong and should not be
ignored.

The *.rej files are now shown by `git status`, which helps located
conflicts when applying patches and lowers the probability that they
will go unnoticed. It is however still easy to overlook the *.orig files
which slowly polute the source tree. That's not as big of a deal as not
noticing a conflict, but it's still not nice.

Drop the *.orig pattern from .gitignore to avoid this and help keep the
source tree clean.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[masahiroy@kernel.org:
I do not have a strong opinion about this. Perhaps some people may have
a different opinion.

If you are someone who wants to ignore *.orig, it is likely you would
want to do so across all projects. Then, $XDG_CONFIG_HOME/git/ignore
would be more suitable for your needs. gitignore(5) suggests, "Patterns
which a user wants Git to ignore in all situations generally go into a
file specified by core.excludesFile in the user's ~/.gitconfig".

Please note that you cannot do the opposite; if *.orig is ignored by
the project's .gitignore, you cannot override the decision because
$XDG_CONFIG_HOME/git/ignore has a lower priority.

If *.orig is sitting on the fence, I'd leave it to the users. ]
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

A long standing issue in the upstream kernel packaging is that the
linux-headers package is not cross-compiled.

For example, you can cross-build Debian packages for arm64 by running
the following command:

  $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bindeb-pkg

However, the generated linux-headers-*_arm64.deb is useless because the
host programs in it were built for your build machine architecture
(likely x86), not arm64.

The Debian kernel maintains its own Makefiles to cross-compile host
tools without relying on Kbuild. [1]

Instead of adding such full custom Makefiles, this commit adds a small
piece of code to cross-compile host programs located under the scripts/
directory.

A straightforward solution is to pass HOSTCC=${CROSS_COMPILE}gcc, but it
would also cross-compile scripts/basic/fixdep, which needs to be native
to process the if_changed_dep macro. (This approach may work under some
circumstances; you can execute foreign architecture programs with the
help of binfmt_misc because Debian systems enable CONFIG_BINFMT_MISC,
but it would require installing QEMU and libc for that architecture.)

A trick is to use the external module build (KBUILD_EXTMOD=), which
does not rebuild scripts/basic/fixdep. ${CC} needs to be able to link
userspace programs (CONFIG_CC_CAN_LINK=y).

There are known limitations:

 - GCC plugins

   It would possible to rebuild GCC plugins for the target architecture
   by passing HOSTCXX=${CROSS_COMPILE}g++ with necessary packages
   installed, but gcc on the installed system emits
   "cc1: error: incompatible gcc/plugin versions".

 - objtool and resolve_btfids

   These are built by the tools build system. They are not covered by
   the current solution. The resulting linux-headers package is broken
   if CONFIG_OBJTOOL or CONFIG_DEBUG_INFO_BTF is enabled.

I only tested this with Debian, but it should work for other package
systems as well.

[1]: https://salsa.debian.org/kernel-team/linux/-/blob/debian/6.9.9-1/debian/rules.real#L586Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Exclude directories and files unnecessary for building external modules:

 - include/config/  (except include/config/{auto.conf,kernel.release})
 - scripts/atomic/
 - scripts/dtc/
 - scripts/kconfig/
 - scripts/mod/mk_elfconfig
 - scripts/package/
 - scripts/unifdef
 - .config
 - *.o
 - .*.cmd

Avoid copying files twice for the following directories:

 - include/generated/
 - arch/*/include/generated/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Endianness is currently detected on compile-time, but we can defer this
until run-time. This change avoids re-executing scripts/mod/mk_elfconfig
even if modpost in the linux-headers package needs to be rebuilt for a
foreign architecture.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

HOST_ELFCLASS is output to elfconfig.h, but it is not used in modpost.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Pull smb client fixes from Steve French:

 - copy_file_range fix

 - two read fixes including read past end of file rc fix and read retry
   crediting fix

 - falloc zero range fix

* tag 'v6.11-rc5-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region
  cifs: Fix copy offload to flush destination region
  netfs, cifs: Fix handling of short DIO read
  cifs: Fix lack of credit renegotiation on read retry

Push bcachefs fixes from Kent Overstreet:
 "The data corruption in the buffered write path is troubling; inode
  lock should not have been able to cause that...

   - Fix a rare data corruption in the rebalance path, caught as a nonce
     inconsistency on encrypted filesystems

   - Revert lockless buffered write path

   - Mark more errors as autofix"

* tag 'bcachefs-2024-08-21' of https://github.com/koverstreet/bcachefs:
  bcachefs: Mark more errors as autofix
  bcachefs: Revert lockless buffered IO path
  bcachefs: Fix bch2_extents_match() false positive
  bcachefs: Fix failure to return error in data_update_index_update()

errors that are known to always be safe to fix should be autofix: this
should be most errors even at this point, but that will need some
thorough review.

note that errors are still logged in the superblock, so we'll still know
that they happened.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We had a report of data corruption on nixos when building installer
images.

https://github.com/NixOS/nixpkgs/pull/321055#issuecomment-2184131334

It seems that writes are being dropped, but only when issued by QEMU,
and possibly only in snapshot mode. It's undetermined if it's write
calls are being dropped or dirty folios.

Further testing, via minimizing the original patch to just the change
that skips the inode lock on non appends/truncates, reveals that it
really is just not taking the inode lock that causes the corruption: it
has nothing to do with the other logic changes for preserving write
atomicity in corner cases.

It's also kernel config dependent: it doesn't reproduce with the minimal
kernel config that ktest uses, but it does reproduce with nixos's distro
config. Bisection the kernel config initially pointer the finger at page
migration or compaction, but it appears that was erroneous; we haven't
yet determined what kernel config option actually triggers it.

Sadly it appears this will have to be reverted since we're getting too
close to release and my plate is full, but we'd _really_ like to fully
debug it.

My suspicion is that this patch is exposing a preexisting bug - the
inode lock actually covers very little in IO paths, and we have a
different lock (the pagecache add lock) that guards against races with
truncate here.

Fixes: 7e64c86c ("bcachefs: Buffered write path now can avoid the inode lock")
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Pull misc fixes from Guenter Roeck.

These are fixes for regressions that Guenther has been reporting, and
the maintainers haven't picked up and sent in. With rc6 fairly imminent,
I'm taking them directly from Guenter.

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  apparmor: fix policy_unpack_test on big endian systems
  Revert "MIPS: csrc-r4k: Apply verification clocksource flags"
  microblaze: don't treat zero reserved memory regions as error

Pull power sequencing fix from Bartosz Golaszewski:
 "A follow-up fix for the power sequencing subsystem. It turned out the
  previous fix for this driver was incomplete and broke the WLAN support
  on some platforms. This addresses the issue.

   - set the direction of the wlan-enable GPIO to output after
     requesting it as-is"

* tag 'pwrseq-fixes-for-v6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  power: sequencing: qcom-wcn: set the wlan-enable GPIO to output

Commit a9aaf1ff ("power: sequencing: request the WLAN enable GPIO
as-is") broke WLAN on boards on which the wlan-enable GPIO enabling the
wifi module isn't in output mode by default. We need to set direction to
output while retaining the value that was already set to keep the ath
module on if it's already started.

Fixes: a9aaf1ff ("power: sequencing: request the WLAN enable GPIO as-is")
Link: https://lore.kernel.org/r/20240823115500.37280-1-brgl@bgdev.plSigned-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for 6.11-rc6.  Included in here are:

   - dwc3 driver fixes for reported issues

   - MAINTAINER file update, marking a driver as unsupported :(

   - cdnsp driver fixes

   - USB gadget driver fix

   - USB sysfs fix

   - other tiny fixes

   - new device ids for usb serial driver

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

* tag 'usb-6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: option: add MeiG Smart SRM825L
  usb: cdnsp: fix for Link TRB with TC
  usb: dwc3: st: add missing depopulate in probe error path
  usb: dwc3: st: fix probed platform device ref count on probe error path
  usb: dwc3: ep0: Don't reset resource alloc flag (including ep0)
  usb: core: sysfs: Unmerge @usb3_hardware_lpm_attr_group in remove_power_attributes()
  usb: typec: fsa4480: Relax CHIP_ID check
  usb: dwc3: xilinx: add missing depopulate in probe error path
  usb: dwc3: omap: add missing depopulate in probe error path
  dt-bindings: usb: microchip,usb2514: Fix reference USB device schema
  usb: gadget: uvc: queue pump work in uvcg_video_enable()
  cdc-acm: Add DISABLE_ECHO quirk for GE HealthCare UI Controller
  usb: cdnsp: fix incorrect index in cdnsp_get_hw_deq function
  usb: dwc3: core: Prevent USB core invalid event buffer address access
  MAINTAINERS: Mark UVC gadget driver as orphan

Pull SCSI fixes from James Bottomley:
 "Minor fixes only.

  The sd.c one ignores a sync cache request if format is in progress
  which can happen if formatting a drive across suspend/resume"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: sd: Ignore command SYNCHRONIZE CACHE error if format in progress
  scsi: aacraid: Fix double-free on probe failure
  scsi: lpfc: Fix overflow build issue

Pull nfsd fix from Chuck Lever:

 - One more write delegation fix

* tag 'nfsd-6.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  nfsd: fix nfsd4_deleg_getattr_conflict in presence of third party lease

Pull xfs fixes from Chandan Babu:

 - Do not call out v1 inodes with non-zero di_nlink field as being
   corrupt

 - Change xfs_finobt_count_blocks() to count "free inode btree" blocks
   rather than "inode btree" blocks

 - Don't report the number of trimmed bytes via FITRIM because the
   underlying storage isn't required to do anything and failed discard
   IOs aren't reported to the caller anyway

 - Fix incorrect setting of rm_owner field in an rmap query

 - Report missing disk offset range in an fsmap query

 - Obtain m_growlock when extending realtime section of the filesystem

 - Reset rootdir extent size hint after extending realtime section of
   the filesystem

* tag 'xfs-6.11-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: reset rootdir extent size hint after growfsrt
  xfs: take m_growlock when running growfsrt
  xfs: Fix missing interval for missing_owner in xfs fsmap
  xfs: use XFS_BUF_DADDR_NULL for daddrs in getfsmap code
  xfs: Fix the owner setting issue for rmap query in xfs fsmap
  xfs: don't bother reporting blocks trimmed via FITRIM
  xfs: xfs_finobt_count_blocks() walks the wrong btree
  xfs: fix folio dirtying for XFILE_ALLOC callers
  xfs: fix di_onlink checking for V1/V2 inodes

Pull ARM SoC fixes from Arnd Bergmann:
 "There is a fairly large number of bug fixes for Qualcomm platforms,
  most of them addressing issues with the devicetree files for the newly
  added Snapdragon X1 based laptops to make them more reliable.

  The Qualcomm driver changes address a few build-time issues as well as
  runtime problems in the tzmem and scm firmware, the USB Type-C driver,
  and the cmd-db and pmic_glink soc drivers.

  The NXP i.MX usually gets a bunch of devicetree fixes that is
  proportional to the number of supported machines. This includes both
  warning fixes and correctness for the 64-bit i.MX9, i.MX8 and
  layerscape platforms, as well as a single fix for a 32-bit i.MX6 based
  board.

  The other changes are the usual minor changes, including an update to
  the MAINTAINERS file, an omap3 dts file and a SoC driver for mpfs
  (risc-v)"

* tag 'arm-fixes-6.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (50 commits)
  firmware: microchip: fix incorrect error report of programming:timeout on success
  soc: qcom: pd-mapper: Fix singleton refcount
  firmware: qcom: tzmem: disable sdm670 platform
  soc: qcom: pmic_glink: Actually communicate when remote goes down
  usb: typec: ucsi: Move unregister out of atomic section
  soc: qcom: pmic_glink: Fix race during initialization
  firmware: qcom: qseecom: remove unused functions
  firmware: qcom: tzmem: fix virtual-to-physical address conversion
  firmware: qcom: scm: Mark get_wq_ctx() as atomic call
  arm64: dts: qcom: x1e80100: Fix Adreno SMMU global interrupt
  arm64: dts: qcom: disable GPU on x1e80100 by default
  arm64: dts: imx8mm-phygate: fix typo pinctrcl-0
  arm64: dts: imx95: correct L3Cache cache-sets
  arm64: dts: imx95: correct a55 power-domains
  arm64: dts: freescale: imx93-tqma9352-mba93xxla: fix typo
  arm64: dts: freescale: imx93-tqma9352: fix CMA alloc-ranges
  ARM: dts: imx6dl-yapp43: Increase LED current to match the yapp4 HW design
  arm64: dts: imx93: update default value for snps,clk-csr
  arm64: dts: freescale: tqma9352: Fix watchdog reset
  arm64: dts: imx8mp-beacon-kit: Fix Stereo Audio on WM8962
  ...

Pull input fix from Dmitry Torokhov:

 - a fix for Cypress PS/2 touchpad for regression introduced in 6.11
   merge window where a timeout condition is incorrectly reported for
   all extended Cypress commands

* tag 'input-for-v6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: cypress_ps2 - fix waiting for command response

Pull pci fixes from Bjorn Helgaas:

 - Add Manivannan Sadhasivam as PCI native host bridge and endpoint
   driver reviewer (Manivannan Sadhasivam)

 - Disable MHI RAM data parity error interrupt for qcom SA8775P SoC to
   work around hardware erratum that causes a constant stream of
   interrupts (Manivannan Sadhasivam)

 - Don't try to fall back to qcom Operating Performance Points (OPP)
   support unless the platform actually supports OPP (Manivannan
   Sadhasivam)

 - Add imx@lists.linux.dev mailing list to MAINTAINERS for NXP
   layerscape and imx6 PCI controller drivers (Frank Li)

* tag 'pci-v6.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  MAINTAINERS: PCI: Add NXP PCI controller mailing list imx@lists.linux.dev
  PCI: qcom: Use OPP only if the platform supports it
  PCI: qcom-ep: Disable MHI RAM data parity error interrupt for SA8775P SoC
  MAINTAINERS: Add Manivannan Sadhasivam as Reviewer for PCI native host bridge and endpoint drivers

Pull block fix from Jens Axboe:
 "Fix for a single regression for WRITE_SAME introduced in the 6.11
  merge window"

* tag 'block-6.11-20240830' of git://git.kernel.dk/linux:
  block: fix detection of unsupported WRITE SAME in blkdev_issue_write_zeroes

Pull io_uring fixes from Jens Axboe:

 - A fix for a regression that happened in 6.11 merge window, where the
   copying of iovecs for compat mode applications got broken for certain
   cases.

 - Fix for a bug introduced in 6.10, where if using recv/send bundles
   with classic provided buffers, the recv/send would fail to set the
   right iovec count. This caused 0 byte send/recv results. Found via
   code coverage testing and writing a test case to exercise it.

* tag 'io_uring-6.11-20240830' of git://git.kernel.dk/linux:
  io_uring/kbuf: return correct iovec count from classic buffer peek
  io_uring/rsrc: ensure compat iovecs are copied correctly

Merge tag 'at91-fixes-6.11' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux into arm/fixes

Microchip AT91 fixes for v6.11

It contains:
- DTS directory update to match all entries not only those starting with
  at91 or sama

Pull lsm fix from Paul Moore:
 "One small patch to correct a NFS permissions problem with SELinux and
  Smack"

* tag 'lsm-pr-20240830' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  selinux,smack: don't bypass permissions check in inode_setsecctx hook

Pull power management fixes from Rafael Wysocki:
 "These fix three issues in the amd-pstate cpufreq driver.

  Specifics:

   - Remove checks for highest performance match on preferred cores when
     updating preferred core ranking in amd-pstate (Mario Limonciello)

   - Make amd-pstate call topology_logical_package_id() instead of
     logical_die_id() to get a socked ID for a CPU (Gautham Shenoy)

   - Fix uninitialized variable in amd_pstate_cpu_boost_update() (Dan
     Carpenter)"

* tag 'pm-6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq/amd-pstate-ut: Don't check for highest perf matching on prefcore
  cpufreq/amd-pstate: Use topology_logical_package_id() instead of logical_die_id()
  cpufreq: amd-pstate: Fix uninitialized variable in amd_pstate_cpu_boost_update()

Pull dmaengine fixes from Vinod Koul:

 - A bunch of dw driver changes to fix the src/dst addr width config

 - Omap driver fix for sglen initialization

 - stm32-dma3 driver lli_size init fix

 - dw edma driver fixes for watermark interrupts and unmasking STOP and
   ABORT interrupts

* tag 'dmaengine-fix-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
  dmaengine: dw-edma: Do not enable watermark interrupts for HDMA
  dmaengine: dw-edma: Fix unmasking STOP and ABORT interrupts for HDMA
  dmaengine: stm32-dma3: Set lli_size after allocation
  dmaengine: ti: omap-dma: Initialize sglen after allocation
  dmaengine: dw: Unify ret-val local variables naming
  dmaengine: dw: Simplify max-burst calculation procedure
  dmaengine: dw: Define encode_maxburst() above prepare_ctllo() callbacks
  dmaengine: dw: Simplify prepare CTL_LO methods
  dmaengine: dw: Add memory bus width verification
  dmaengine: dw: Add peripheral bus width verification

Pull phy fixes from Vinod Koul:

 - Qualcomm QMP X1E80100 PCIe Gen4 PHY initialisation fix

 - Freescale imx8mq tuning parameter name fix

 - Samsung exynos5 fir for error code in probe()

 - Xilinx Zynqmp SGMII linkup failure fix

* tag 'phy-fixes-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy:
  phy: xilinx: phy-zynqmp: Fix SGMII linkup failure on resume
  phy: exynos5-usbdrd: fix error code in probe()
  phy: fsl-imx8mq-usb: fix tuning parameter name
  phy: qcom: qmp-pcie: Fix X1E80100 PCIe Gen4 PHY initialisation

Pull soundwire fix from Vinod Koul:

 - Single fix for non-continous port map programming

* tag 'soundwire-6.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire:
  soundwire: stream: fix programming slave ports for non-continous port maps

Pull iommu fixes from Joerg Roedel:

 - Fix a device-stall problem in bad io-page-fault setups (faults
   received from devices with no supporting domain attached).

 - Context flush fix for Intel VT-d.

 - Do not allow non-read+non-write mapping through iommufd as most
   implementations can not handle that.

 - Fix a possible infinite-loop issue in map_pages() path.

 - Add Jean-Philippe as reviewer for SMMUv3 SVA support

* tag 'iommu-fixes-v6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
  MAINTAINERS: Add Jean-Philippe as SMMUv3 SVA reviewer
  iommu: Do not return 0 from map_pages if it doesn't do anything
  iommufd: Do not allow creating areas without READ or WRITE
  iommu/vt-d: Fix incorrect domain ID in context flush helper
  iommu: Handle iommu faults for a bad iopf setup

Add imx mailing list imx@lists.linux.dev for PCI controller of NXP chips
(Layerscape and iMX).

Link: https://lore.kernel.org/r/20240826202740.970015-1-Frank.Li@nxp.comSigned-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Richard Zhu <hongxing.zhu@nxp.com>

io_provided_buffers_select() returns 0 to indicate success, but it should
be returning 1 to indicate that 1 vec was mapped. This causes peeking
to fail with classic provided buffers, and while that's not a use case
that anyone should use, it should still work correctly.

The end result is that no buffer will be selected, and hence a completion
with '0' as the result will be posted, without a buffer attached.

Fixes: 35c8711c ("io_uring/kbuf: add helpers for getting/peeking multiple buffers")
Signed-off-by: Jens Axboe <axboe@kernel.dk>