Without EXCLUSIVE_SYSTEM_RAM, users are allowed to map arbitrary
physical memory regions into the userspace via /dev/mem. At the same
time, pages may change their properties (e.g., from anonymous pages to
named pages) while they are still being mapped in the userspace, leading
to "corruption" detected by the page table check.

To avoid these false positives, this patch makes PAGE_TABLE_CHECK
depends on EXCLUSIVE_SYSTEM_RAM. This dependency is understandable
because PAGE_TABLE_CHECK is a hardening technique but /dev/mem without
STRICT_DEVMEM (i.e., !EXCLUSIVE_SYSTEM_RAM) is itself a security
problem.

Even with EXCLUSIVE_SYSTEM_RAM, I/O pages may be still allowed to be
mapped via /dev/mem. However, these pages are always considered as named
pages, so they won't break the logic used in the page table check.

Cc: <stable@vger.kernel.org> # 5.17
Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/r/20230515130958.32471-4-lrh2000@pku.edu.cnSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When hcd->localmem_pool is non-null, localmem_pool is used to allocate
DMA memory. In this case, the dma address will be properly returned (in
dma_handle), and dma_mmap_coherent should be used to map this memory
into the user space. However, the current implementation uses
pfn_remap_range, which is supposed to map normal pages.

Instead of repeating the logic in the memory allocation function, this
patch introduces a more robust solution. Here, the type of allocated
memory is checked by testing whether dma_handle is properly set. If
dma_handle is properly returned, it means some DMA pages are allocated
and dma_mmap_coherent should be used to map them. Otherwise, normal
pages are allocated and pfn_remap_range should be called. This ensures
that the correct mmap functions are used consistently, independently
with logic details that determine which type of memory gets allocated.

Fixes: a0e710a7 ("USB: usbfs: fix mmap dma mismatch")
Cc: stable@vger.kernel.org
Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
Link: https://lore.kernel.org/r/20230515130958.32471-3-lrh2000@pku.edu.cnSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The current implementation of usbdev_mmap uses usb_alloc_coherent to
allocate memory pages that will later be mapped into the user space.
Meanwhile, usb_alloc_coherent employs three different methods to
allocate memory, as outlined below:
 * If hcd->localmem_pool is non-null, it uses gen_pool_dma_alloc to
   allocate memory;
 * If DMA is not available, it uses kmalloc to allocate memory;
 * Otherwise, it uses dma_alloc_coherent.

However, it should be noted that gen_pool_dma_alloc does not guarantee
that the resulting memory will be page-aligned. Furthermore, trying to
map slab pages (i.e., memory allocated by kmalloc) into the user space
is not resonable and can lead to problems, such as a type confusion bug
when PAGE_TABLE_CHECK=y [1].

To address these issues, this patch introduces hcd_alloc_coherent_pages,
which addresses the above two problems. Specifically,
hcd_alloc_coherent_pages uses gen_pool_dma_alloc_align instead of
gen_pool_dma_alloc to ensure that the memory is page-aligned. To replace
kmalloc, hcd_alloc_coherent_pages directly allocates pages by calling
__get_free_pages.

Reported-by: syzbot+fcf1a817ceb50935ce99@syzkaller.appspotmail.comm
Closes: https://lore.kernel.org/lkml/000000000000258e5e05fae79fc1@google.com/ [1]
Fixes: f7d34b44 ("USB: Add support for usbfs zerocopy.")
Fixes: ff2437be ("usb: host: Fix excessive alignment restriction for local memory allocations")
Cc: stable@vger.kernel.org
Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20230515130958.32471-2-lrh2000@pku.edu.cnSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The "snps,hsphy_interface" is string, not u8. Fix the type.

Fixes: 389d7765 ("dt-bindings: usb: Convert DWC USB3 bindings to DT schema")
Cc: stable <stable@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20230515172456.179049-1-marex@denx.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The "udc" pointer was never set in the probe() function so it will
lead to a NULL dereference in udc_pci_remove() when we do:

	usb_del_gadget_udc(&udc->gadget);
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/ZG+A/dNpFWAlCChk@kiliSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

While exercising the unbind path, with the current implementation
the functionfs_unbind would be calling which waits for the ffs->mutex
to be available, however within the same time ffs_ep0_read is invoked
& if no setup packets are pending, it will invoke function
wait_event_interruptible_exclusive_locked_irq which by definition waits
for the ev.count to be increased inside the same mutex for which
functionfs_unbind is waiting.
This creates deadlock situation because the functionfs_unbind won't
get the lock until ev.count is increased which can only happen if
the caller ffs_func_unbind can proceed further.

Following is the illustration:

	CPU1				CPU2

ffs_func_unbind()		ffs_ep0_read()
				mutex_lock(ffs->mutex)
				wait_event(ffs->ev.count)
functionfs_unbind()
  mutex_lock(ffs->mutex)
  mutex_unlock(ffs->mutex)

ffs_event_add()

<deadlock>

Fix this by moving the event unbind before functionfs_unbind
to ensure the ev.count is incrased properly.

Fixes: 6a19da11 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait")
Cc: stable <stable@kernel.org>
Signed-off-by: Uttkarsh Aggarwal <quic_uaggarwa@quicinc.com>
Link: https://lore.kernel.org/r/20230525092854.7992-1-quic_uaggarwa@quicinc.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

At iMX8QM platform, enable NCM gadget and run 'iperf3 -s'.
At host, run 'iperf3 -V -c fe80::6863:98ff:feef:3e0%enxc6e147509498'

[  5]   0.00-1.00   sec  1.55 MBytes  13.0 Mbits/sec   90   4.18 KBytes
[  5]   1.00-2.00   sec  1.44 MBytes  12.0 Mbits/sec   75   4.18 KBytes
[  5]   2.00-3.00   sec  1.48 MBytes  12.4 Mbits/sec   75   4.18 KBytes

Expected speed should be bigger than 300Mbits/sec.

The root cause of this performance drop was found to be data corruption
happening at 4K borders in some Ethernet packets, leading to TCP
checksum errors. This corruption occurs from the position
(4K - (address & 0x7F)) to 4K. The u_ether function's allocation of
skb_buff reserves 64B, meaning all RX addresses resemble 0xXXXX0040.

Force trb_burst_size to 16 can fix this problem.

Cc: stable@vger.kernel.org
Fixes: 7733f6c3 ("usb: cdns3: Add Cadence USB3 DRD Driver")
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20230518154946.3666662-1-Frank.Li@nxp.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull x86 cpu fix from Thomas Gleixner:
 "A single fix for x86:

   - Prevent a bogus setting for the number of HT siblings, which is
     caused by the CPUID evaluation trainwreck of X86. That recomputes
     the value for each CPU, so the last CPU "wins". That can cause
     completely bogus sibling values"

* tag 'x86-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/topology: Fix erroneous smp_num_siblings on Intel Hybrid platforms

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

   - Make the MSR-readout based CHA discovery work around broken
     discovery tables in some SPR firmwares.

   - Prevent saving PEBS configuration which has software bits set that
     cause a crash when restored into the relevant MSR"

* tag 'perf-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/uncore: Correct the number of CHAs on SPR
  perf/x86/intel: Save/restore cpuc->active_pebs_data_cfg when using guest PEBS

Pull unwinder fixes from Thomas Gleixner:
 "A set of unwinder and tooling fixes:

   - Ensure that the stack pointer on x86 is aligned again so that the
     unwinder does not read past the end of the stack

   - Discard .note.gnu.property section which has a pointlessly
     different alignment than the other note sections. That confuses
     tooling of all sorts including readelf, libbpf and pahole"

* tag 'objtool-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/show_trace_log_lvl: Ensure stack pointer is aligned, again
  vmlinux.lds.h: Discard .note.gnu.property section

Pull debugobjects fixes from Thomas Gleixner:
 "Two fixes for debugobjects:

   - Prevent the allocation path from waking up kswapd.

     That's a long standing issue due to the GFP_ATOMIC allocation flag.
     As debug objects can be invoked from pretty much any context waking
     kswapd can end up in arbitrary lock chains versus the waitqueue
     lock

   - Correct the explicit lockdep wait-type violation in
     debug_object_fill_pool()"

* tag 'core-debugobjects-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  debugobjects: Don't wake up kswapd from fill_pool()
  debugobjects,locking: Annotate debug_object_fill_pool() wait type violation

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

   - Prevent loss of state in the MIPS GIC interrupt controller

   - Disable pseudo NMIs on Mediatek based Chromebooks as they have
     firmware issues which cause instantenous chrashes and freezes wen
     pseudo NMIs are used

   - Fix the error handling path in the MBIGEN driver and a defined but
     not used warning in the meson-gpio interrupt chip driver"

* tag 'irq-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/mbigen: Unify the error handling in mbigen_of_create_domain()
  irqchip/meson-gpio: Mark OF related data as maybe unused
  irqchip/mips-gic: Use raw spinlock for gic_lock
  irqchip/mips-gic: Don't touch vl_map if a local interrupt is not routable
  irqchip/gic-v3: Disable pseudo NMIs on Mediatek devices w/ firmware issues
  dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW

Pull MIPS fixes from Thomas Bogendoerfer:

 - fixes to get alchemy platform back in shape

 - fix for initrd detection

* tag 'mips-fixes_6.4_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  mips: Move initrd_start check after initrd address sanitisation.
  MIPS: Alchemy: fix dbdma2
  MIPS: Restore Au1300 support
  MIPS: unhide PATA_PLATFORM

Pull powerpc fix from Michael Ellerman:

 - Reinstate ARCH_FORCE_MAX_ORDER ranges to fix various breakage

* tag 'powerpc-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/mm: Reinstate ARCH_FORCE_MAX_ORDER ranges

Pull xen fixes from Juergen Gross:

 - a double free fix in the Xen pvcalls backend driver

 - a fix for a regression causing the MSI related sysfs entries to not
   being created in Xen PV guests

 - a fix in the Xen blkfront driver for handling insane input data
   better

* tag 'for-linus-6.4-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/pci/xen: populate MSI sysfs entries
  xen/pvcalls-back: fix double frees with pvcalls_new_active_socket()
  xen/blkfront: Only check REQ_FUA for writes

Pull char/misc fixes from Greg KH:
 "Here are some small driver fixes for 6.4-rc4. They are just two
  different types:

   - binder fixes and reverts for reported problems and regressions in
     the binder "driver".

   - coresight driver fixes for reported problems.

  All of these have been in linux-next for over a week with no reported
  problems"

* tag 'char-misc-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  binder: fix UAF of alloc->vma in race with munmap()
  binder: add lockless binder_alloc_(set|get)_vma()
  Revert "android: binder: stop saving a pointer to the VMA"
  Revert "binder_alloc: add missing mmap_lock calls when using the VMA"
  binder: fix UAF caused by faulty buffer cleanup
  coresight: perf: Release Coresight path when alloc trace id failed
  coresight: Fix signedness bug in tmc_etr_buf_insert_barrier_packet()

Pull compute express link fixes from Dan Williams:
 "The 'media ready' series prevents the driver from acting on bad
  capacity information, and it moves some checks earlier in the init
  sequence which impacts topics in the queue for 6.5.

  Additional hotplug testing uncovered a missing enable for memory
  decode. A debug crash fix is also included.

  Summary:

   - Stop trusting capacity data before the "media ready" indication

   - Add missing HDM decoder capability enable for the cold-plug case

   - Fix a debug message induced crash"

* tag 'cxl-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl: Explicitly initialize resources when media is not ready
  cxl/port: Fix NULL pointer access in devm_cxl_add_port()
  cxl: Move cxl_await_media_ready() to before capacity info retrieval
  cxl: Wait Memory_Info_Valid before access memory related info
  cxl/port: Enable the HDM decoder capability for switch ports

Pull ARM SoC fixes from Arnd Bergmann:
 "There have not been a lot of fixes for for the soc tree in 6.4, but
  these have been sitting here for too long.

  For the devicetree side, there is one minor warning fix for vexpress,
  the rest all all for the the NXP i.MX platforms: SoC specific bugfixes
  for the iMX8 clocks and its USB-3.0 gadget device, as well as board
  specific fixes for regulators and the phy on some of the i.MX boards.

  The microchip risc-v and arm32 maintainers now also add a shared
  maintainer file entry for the arm64 parts.

  The remaining fixes are all for firmware drivers, addressing mistakes
  in the optee, scmi and ff-a firmware driver implementation, mostly in
  the error handling code, incorrect use of the alloc_workqueue()
  interface in SCMI, and compatibility with corner cases of the firmware
  implementation"

* tag 'arm-fixes-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  MAINTAINERS: update arm64 Microchip entries
  arm64: dts: imx8: fix USB 3.0 Gadget Failure in QM & QXPB0 at super speed
  dt-binding: cdns,usb3: Fix cdns,on-chip-buff-size type
  arm64: dts: colibri-imx8x: delete adc1 and dsp
  arm64: dts: colibri-imx8x: fix iris pinctrl configuration
  arm64: dts: colibri-imx8x: move pinctrl property from SoM to eval board
  arm64: dts: colibri-imx8x: fix eval board pin configuration
  arm64: dts: imx8mp: Fix video clock parents
  ARM: dts: imx6qdl-mba6: Add missing pvcie-supply regulator
  ARM: dts: imx6ull-dhcor: Set and limit the mode for PMIC buck 1, 2 and 3
  arm64: dts: imx8mn-var-som: fix PHY detection bug by adding deassert delay
  arm64: dts: imx8mn: Fix video clock parents
  firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors
  firmware: arm_ffa: Fix FFA device names for logical partitions
  firmware: arm_ffa: Fix usage of partition info get count flag
  firmware: arm_ffa: Check if ffa_driver remove is present before executing
  arm64: dts: arm: add missing cache properties
  ARM: dts: vexpress: add missing cache properties
  firmware: arm_scmi: Fix incorrect alloc_workqueue() invocation
  optee: fix uninited async notif value

Pull PCI fix from Bjorn Helgaas:

 - Quirk Ice Lake Root Ports to work around DPC log size issue (Mika
   Westerberg)

* tag 'pci-v6.4-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  PCI/DPC: Quirk PIO log size for Intel Ice Lake Root Ports

Pull VFIO fix from Alex Williamson:

 - Test for and return error for invalid pfns through the pin pages
   interface (Yan Zhao)

* tag 'vfio-v6.4-rc4' of https://github.com/awilliam/linux-vfio:
  vfio/type1: check pfn valid before converting to struct page

Pull block fixes from Jens Axboe:
 "A few fixes for the storage side of things:

   - Fix bio caching condition for passthrough IO (Anuj)

   - end-of-device check fix for zero sized devices (Christoph)

   - Update Paolo's email address

   - NVMe pull request via Keith with a single quirk addition

   - Fix regression in how wbt enablement is done (Yu)

   - Fix race in active queue accounting (Tian)"

* tag 'block-6.4-2023-05-26' of git://git.kernel.dk/linux:
  NVMe: Add MAXIO 1602 to bogus nid list.
  block: make bio_check_eod work for zero sized devices
  block: fix bio-cache for passthru IO
  block, bfq: update Paolo's address in maintainer list
  blk-mq: fix race condition in active queue accounting
  blk-wbt: fix that wbt can't be disabled by default

Pull io_uring fix from Jens Axboe:
 "Just a single fix for the conditional schedule with the SQPOLL thread,
  dropping the uring_lock if we do need to reschedule"

* tag 'io_uring-6.4-2023-05-26' of git://git.kernel.dk/linux:
  io_uring: unlock sqd->lock before sq thread release CPU

Pull thermal control fix from Rafael Wysocki:
 "Fix a regression introduced inadvertently during the 6.3 cycle by a
  commit making the Intel int340x thermal driver use sysfs_emit_at()
  instead of scnprintf() (Srinivas Pandruvada)"

* tag 'thermal-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  thermal: intel: int340x: Add new line for UUID display

Pull power management fixes from Rafael Wysocki:
 "Fix three issues related to the ->fast_switch callback in the AMD
  P-state cpufreq driver (Gautham R. Shenoy and Wyes Karny)"

* tag 'pm-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: amd-pstate: Update policy->cur in amd_pstate_adjust_perf()
  cpufreq: amd-pstate: Remove fast_switch_possible flag from active driver
  cpufreq: amd-pstate: Add ->fast_switch() callback

When media is not ready do not assume that the capacity information from
the identify command is valid, i.e. ->total_bytes
->partition_align_bytes ->{volatile,persistent}_only_bytes. Explicitly
zero out the capacity resources and exit early.

Given zero-init of those fields this patch is functionally equivalent to
the prior state, but it improves readability and robustness going
forward.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168506118166.3004974.13523455340007852589.stgit@djiang5-mobl3Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Pull gpio fixes from Bartosz Golaszewski:

 - fix incorrect output in in-tree gpio tools

 - fix a shell coding issue in gpio-sim selftests

 - correctly set the permissions for debugfs attributes exposed by
   gpio-mockup

 - fix chip name and pin count in gpio-f7188x for one of the supported
   models

 - fix numberspace pollution when using dynamically and statically
   allocated GPIOs together

* tag 'gpio-fixes-for-v6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio-f7188x: fix chip name and pin count on Nuvoton chip
  gpiolib: fix allocation of mixed dynamic/static GPIOs
  gpio: mockup: Fix mode of debugfs files
  selftests: gpio: gpio-sim: Fix BUG: test FAILED due to recent change
  tools: gpio: fix debounce_period_us output of lsgpio

Pull btrfs fixes from David Sterba:

 - handle memory allocation error in checksumming helper (reported by
   syzbot)

 - fix lockdep splat when aborting a transaction, add NOFS protection
   around invalidate_inode_pages2 that could allocate with GFP_KERNEL

 - reduce chances to hit an ENOSPC during scrub with RAID56 profiles

* tag 'for-6.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: use nofs when cleaning up aborted transactions
  btrfs: handle memory allocation failure in btrfs_csum_one_bio
  btrfs: scrub: try harder to mark RAID56 block groups read-only

Pull drm fixes from Dave Airlie:
 "This week's collection is pretty spread out, accel/qaic has a bunch of
  fixes, amdgpu, then lots of single fixes across a bunch of places.

  core:
   - fix drmm_mutex_init lock class

  mgag200:
   - fix gamma lut initialisation

  pl111:
   - fix FB depth on IMPD-1 framebuffer

  amdgpu:
   - Fix missing BO unlocking in KIQ error path
   - Avoid spurious secure display error messages
   - SMU13 fix
   - Fix an OD regression
   - GPU reset display IRQ warning fix
   - MST fix

  radeon:
   - Fix a DP regression

  i915:
   - PIPEDMC disabling fix for bigjoiner config

  panel:
   - fix aya neo air plus quirk

  sched:
   - remove redundant NULL check

  qaic:
   - fix NNC message corruption
   - Grab ch_lock during QAIC_ATTACH_SLICE_BO
   - Flush the transfer list again
   - Validate if BO is sliced before slicing
   - Validate user data before grabbing any lock
   - initialize ret variable to 0
   - silence some uninitialized variable warnings"

* tag 'drm-fixes-2023-05-26' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: Have Payload Properly Created After Resume
  drm/amd/display: Fix warning in disabling vblank irq
  drm/amd/pm: Fix output of pp_od_clk_voltage
  drm/amd/pm: add missing NotifyPowerSource message mapping for SMU13.0.7
  drm/radeon: reintroduce radeon_dp_work_func content
  drm/amdgpu: don't enable secure display on incompatible platforms
  drm:amd:amdgpu: Fix missing buffer object unlock in failure path
  accel/qaic: Fix NNC message corruption
  accel/qaic: Grab ch_lock during QAIC_ATTACH_SLICE_BO
  accel/qaic: Flush the transfer list again
  accel/qaic: Validate if BO is sliced before slicing
  accel/qaic: Validate user data before grabbing any lock
  accel/qaic: initialize ret variable to 0
  drm/i915: Fix PIPEDMC disabling for a bigjoiner configuration
  drm: fix drmm_mutex_init()
  drm/sched: Remove redundant check
  drm: panel-orientation-quirks: Change Air's quirk to support Air Plus
  accel/qaic: silence some uninitialized variable warnings
  drm/pl111: Fix FB depth on IMPD-1 framebuffer
  drm/mgag200: Fix gamma lut not initialized.

I tried to streamline our user memory copy code fairly aggressively in
commit adfcf423 ("x86: don't use REP_GOOD or ERMS for user memory
copies"), in order to then be able to clean up the code and inline the
modern FSRM case in commit 577e6a7f ("x86: inline the 'rep movs' in
user copies for the FSRM case").

We had reports [1] of that causing regressions earlier with blogbench,
but that turned out to be a horrible benchmark for that case, and not a
sufficient reason for re-instating "rep movsb" on older machines.

However, now Eric Dumazet reported [2] a regression in performance that
seems to be a rather more real benchmark, where due to the removal of
"rep movs" a TCP stream over a 100Gbps network no longer reaches line
speed.

And it turns out that with the simplified the calling convention for the
non-FSRM case in commit 427fda2c ("x86: improve on the non-rep
'copy_user' function"), re-introducing the ERMS case is actually fairly
simple.

Of course, that "fairly simple" is glossing over several missteps due to
having to fight our assembler alternative code.  This code really wanted
to rewrite a conditional branch to have two different targets, but that
made objtool sufficiently unhappy that this instead just ended up doing
a choice between "jump to the unrolled loop, or use 'rep movsb'
directly".

Let's see if somebody finds a case where the kernel memory copies also
care (see commit 68674f94: "x86: don't use REP_GOOD or ERMS for
small memory copies").  But Eric does argue that the user copies are
special because networking tries to copy up to 32KB at a time, if
order-3 pages allocations are possible.

In-kernel memory copies are typically small, unless they are the special
"copy pages at a time" kind that still use "rep movs".

Link: https://lore.kernel.org/lkml/202305041446.71d46724-yujie.liu@intel.com/ [1]
Link: https://lore.kernel.org/lkml/CANn89iKUbyrJ=r2+_kK+sb2ZSSHifFZ7QkPLDpAtkJ8v4WUumA@mail.gmail.com/ [2]
Reported-and-tested-by: Eric Dumazet <edumazet@google.com>
Fixes: adfcf423 ("x86: don't use REP_GOOD or ERMS for user memory copies")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull NVMe fix from Keith:

"nvme fixes for 6.4

 One nvme quirk (Tatsuki)"

* tag 'nvme-6.4-2023-05-26' of git://git.infradead.org/nvme:
  NVMe: Add MAXIO 1602 to bogus nid list.

HIKSEMI FUTURE M.2 SSD uses the same dummy nguid and eui64.
I confirmed it with my two devices.

This patch marks the controller as NVME_QUIRK_BOGUS_NID.

---------------------------------------------------------
sugi@tempest:~% sudo nvme id-ctrl /dev/nvme0
NVME Identify Controller:
vid       : 0x1e4b
ssvid     : 0x1e4b
sn        : 30096022612
mn        : HS-SSD-FUTURE 2048G
fr        : SN10542
rab       : 0
ieee      : 000000
cmic      : 0
mdts      : 7
cntlid    : 0
ver       : 0x10400
rtd3r     : 0x7a120
rtd3e     : 0x1e8480
oaes      : 0x200
ctratt    : 0x2
rrls      : 0
cntrltype : 1
fguid     : 00000000-0000-0000-0000-000000000000
<snip...>
---------------------------------------------------------

---------------------------------------------------------
sugi@tempest:~% sudo nvme id-ns /dev/nvme0n1
NVME Identify Namespace 1:
<snip...>
nguid   : 00000000000000000000000000000000
eui64   : 0000000000000002
lbaf  0 : ms:0   lbads:9  rp:0 (in use)
---------------------------------------------------------
Signed-off-by: Tatsuki Sugiura <sugi@nemui.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

Merge tag 'ffa-fixes-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/fixes

Arm FF-A fixes for v6.4

Quite a few fixes to address set of assorted issues:
1. NULL pointer dereference if the ffa driver doesn't provide remove()
   callback as it is currently executed unconditionally
2. FF-A core probe failure on systems with v1.0 firmware as the new
   partition info get count flag is used unconditionally
3. Failure to register more than one logical partition or service within
   the same physical partition as the device name contains only VM ID
   which will be same for all but each will have unique UUID.
4. Rejection of certain memory interface transmissions by the receivers
   (secure partitions) as few MBZ fields are non-zero due to lack of
   explicit re-initialization of those fields

* tag 'ffa-fixes-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors
  firmware: arm_ffa: Fix FFA device names for logical partitions
  firmware: arm_ffa: Fix usage of partition info get count flag
  firmware: arm_ffa: Check if ffa_driver remove is present before executing

Link: https://lore.kernel.org/r/20230509143453.1188753-1-sudeep.holla@arm.comSigned-off-by: Arnd Bergmann <arnd@arndb.de>

drm-misc-fixes for v6.4-rc4:
- A few non-trivial fixes to qaic.
- Fix drmm_mutex_init always using same lock class.
- Fix pl111 fb depth.
- Fix uninitialised gamma lut in mgag200.
- Add Aya Neo Air Plus quirk.
- Trivial null check removal in scheduler.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/d19f748c-2c5b-8140-5b05-a8282dfef73e@linux.intel.com

Merge tag 'amd-drm-fixes-6.4-2023-05-24' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes

amd-drm-fixes-6.4-2023-05-24:

amdgpu:
- Fix missing BO unlocking in KIQ error path
- Avoid spurious secure display error messages
- SMU13 fix
- Fix an OD regression
- GPU reset display IRQ warning fix
- MST fix

radeon:
- Fix a DP regression
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230524211238.7749-1-alexander.deucher@amd.com

Merge tag 'drm-intel-fixes-2023-05-25' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

PIPEDMC disabling fix for bigjoiner config
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ZG9aROGyc947/J1l@jlahtine-mobl.ger.corp.intel.com

Pull smb directory moves and client fixes from Steve French:
 "Four smb3 client fixes (three of which marked for stable) and three
  patches to move of fs/cifs and fs/ksmbd to a new common "fs/smb"
  parent directory

   - Move the client and server source directories to a common parent
     directory:

       fs/cifs -> fs/smb/client
       fs/ksmbd -> fs/smb/server
       fs/smbfs_common -> fs/smb/common

   - important readahead fix

   - important fix for SMB1 regression

   - fix for missing mount option ("mapchars") in mount API conversion

   - minor debugging improvement"

* tag '6.4-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: move Documentation/filesystems/cifs to Documentation/filesystems/smb
  cifs: correct references in Documentation to old fs/cifs path
  smb: move client and server files to common directory fs/smb
  cifs: mapchars mount option ignored
  smb3: display debug information better for encryption
  cifs: fix smb1 mount regression
  cifs: Fix cifs_limit_bvec_subset() to correctly check the maxmimum size

Pull parisc architecture fixes from Helge Deller:
 "Quite a bunch of real bugfixes in here and most of them are tagged for
  backporting: A fix for cache flushing from irq context, a kprobes &
  kgdb breakpoint handling fix, and a fix in the alternative code
  patching function to take care of CPU hotplugging.

  parisc now provides LOCKDEP support and comes with a lightweight
  spinlock check. Both features helped me to find the cache flush bug.

  Additionally writing the AGP gatt has been fixed, the machine allows
  the user to reboot after a system halt and arch_sync_dma_for_cpu() has
  been optimized for PCXL PCUs.

  Summary:

   - Fix flush_dcache_page() for usage from irq context

   - Handle kprobes breakpoints only in kernel context

   - Handle kgdb breakpoints only in kernel context

   - Use num_present_cpus() in alternative patching code

   - Enable LOCKDEP support

   - Add lightweight spinlock checks

   - Flush AGP gatt writes and adjust gatt mask in parisc_agp_mask_memory()

   - Allow to reboot machine after system halt

   - Improve cache flushing for PCXL in arch_sync_dma_for_cpu()"

* tag 'parisc-for-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix flush_dcache_page() for usage from irq context
  parisc: Handle kgdb breakpoints only in kernel context
  parisc: Handle kprobes breakpoints only in kernel context
  parisc: Allow to reboot machine after system halt
  parisc: Enable LOCKDEP support
  parisc: Add lightweight spinlock checks
  parisc: Use num_present_cpus() in alternative patching code
  parisc: Flush gatt writes and adjust gatt mask in parisc_agp_mask_memory()
  parisc: Improve cache flushing for PCXL in arch_sync_dma_for_cpu()

It turns out that udev under certain circumstances will concurrently try
to load the same modules over-and-over excessively.  This isn't a kernel
bug, but it ends up affecting the kernel, to the point that under
certain circumstances we can fail to boot, because the kernel uses a lot
of memory to read all the module data all at once.

Note that it isn't a memory leak, it's just basically a thundering herd
problem happening at bootup with a lot of CPUs, with the worst cases
then being pretty bad.

Admittedly the worst situations are somewhat contrived: lots and lots of
CPUs, not a lot of memory, and KASAN enabled to make it all slower and
as such (unintentionally) exacerbate the problem.

Luis explains: [1]

 "My best assessment of the situation is that each CPU in udev ends up
  triggering a load of duplicate set of modules, not just one, but *a
  lot*. Not sure what heuristics udev uses to load a set of modules per
  CPU."

Petr Pavlu chimes in: [2]

 "My understanding is that udev workers are forked. An initial kmod
  context is created by the main udevd process but no sharing happens
  after the fork. It means that the mentioned memory pool logic doesn't
  really kick in.

  Multiple parallel load requests come from multiple udev workers, for
  instance, each handling an udev event for one CPU device and making
  the exactly same requests as all others are doing at the same time.

  The optimization idea would be to recognize these duplicate requests
  at the udevd/kmod level and converge them"

Note that module loading has tried to mitigate this issue before, see
for example commit 064f4536 ("module: avoid allocation if module is
already present and ready"), which has a few ASCII graphs on memory use
due to this same issue.

However, while that noticed that the module was already loaded, and
exited with an error early before spending any more time on setting up
the module, it didn't handle the case of multiple concurrent module
loads all being active - but not complete - at the same time.

Yes, one of them will eventually win the race and finalize its copy, and
the others will then notice that the module already exists and error
out, but while this all happens, we have tons of unnecessary concurrent
work being done.

Again, the real fix is for udev to not do that (maybe it should use
threads instead of fork, and have actual shared data structures and not
cause duplicate work). That real fix is apparently not trivial.

But it turns out that the kernel already has a pretty good model for
dealing with concurrent access to the same file: the i_writecount of the
inode.

In fact, the module loading already indirectly uses 'i_writecount' ,
because 'kernel_file_read()' will in fact do

	ret = deny_write_access(file);
	if (ret)
		return ret;
	...
	allow_write_access(file);

around the read of the file data.  We do not allow concurrent writes to
the file, and return -ETXTBUSY if the file was open for writing at the
same time as the module data is loaded from it.

And the solution to the reader concurrency problem is to simply extend
this "no concurrent writers" logic to simply be "exclusive access".

Note that "exclusive" in this context isn't really some absolute thing:
it's only exclusion from writers and from other "special readers" that
do this writer denial.  So we simply introduce a variation of that
"deny_write_access()" logic that not only denies write access, but also
requires that this is the _only_ such access that denies write access.

Which means that you can't start loading a module that is already being
loaded as a module by somebody else, or you will get the same -ETXTBSY
error that you would get if there were writers around.

[ It also means that you can't try to load a currently executing
  executable as a module, for the same reason: executables do that same
  "deny_write_access()" thing, and that's obviously where the whole
  ETXTBSY logic traditionally came from.

  This is not a problem for kernel modules, since the set of normal
  executable files and kernel module files is entirely disjoint. ]

This new function is called "exclusive_deny_write_access()", and the
implementation is trivial, in that it's just an atomic decrement of
i_writecount if it was 0 before.

To use that new exclusivity check, all we then do is wrap the module
loading with that exclusive_deny_write_access()() / allow_write_access()
pair.  The actual patch is a bit bigger than that, because we want to
surround not just the "load file data" part, but the whole module setup,
to get maximum exclusion.

So this ends up splitting up "finit_module()" into a few helper
functions to make it all very clear and legible.

In Luis' test-case (bringing up 255 vcpu's in a virtual machine [3]),
the "wasted vmalloc" space (ie module data read into a vmalloc'ed area
in order to be loaded as a module, but then discarded because somebody
else loaded the same module instead) dropped from 1.8GiB to 474kB.  Yes,
that's gigabytes to kilobytes.

It doesn't drop completely to zero, because even with this change, you
can still end up having completely serial pointless module loads, where
one udev process has loaded a module fully (and thus the kernel has
released that exclusive lock on the module file), and then another udev
process tries to load the same module again.

So while we cannot fully get rid of the fundamental bug in user space,
we _can_ get rid of the excessive concurrent thundering herd effect.

A couple of final side notes on this all:

 - This tweak only affects the "finit_module()" system call, which gives
   the kernel a file descriptor with the module data.

   You can also just feed the module data as raw data from user space
   with "init_module()" (note the lack of 'f' at the beginning), and
   obviously for that case we do _not_ have any "exclusive read" logic.

   So if you absolutely want to do things wrong in user space, and try
   to load the same module multiple times, and error out only later when
   the kernel ends up saying "you can't load the same module name
   twice", you can still do that.

   And in fact, some distros will do exactly that, because they will
   uncompress the kernel module data in user space before feeding it to
   the kernel (mainly because they haven't started using the new kernel
   side decompression yet).

   So this is not some absolute "you can't do concurrent loads of the
   same module". It's literally just a very simple heuristic that will
   catch it early in case you try to load the exact same module file at
   the same time, and in that case avoid a potentially nasty situation.

 - There is another user of "deny_write_access()": the verity code that
   enables fs-verity on a file (the FS_IOC_ENABLE_VERITY ioctl).

   If you use fs-verity and you care about verifying the kernel modules
   (which does make sense), you should do it *before* loading said
   kernel module. That may sound obvious, but now the implementation
   basically requires it. Because if you try to do it concurrently, the
   kernel may refuse to load the module file that is being set up by the
   fs-verity code.

 - This all will obviously mean that if you insist on loading the same
   module in parallel, only one module load will succeed, and the others
   will return with an error.

   That was true before too, but what is different is that the -ETXTBSY
   error can be returned *before* the success case of another process
   fully loading and instantiating the module.

   Again, that might sound obvious, and it is indeed the whole point of
   the whole change: we are much quicker to notice the whole "you're
   already in the process of loading this module".

   So it's very much intentional, but it does mean that if you just
   spray the kernel with "finit_module()", and expect that the module is
   immediately loaded afterwards without checking the return value, you
   are doing something horribly horribly wrong.

   I'd like to say that that would never happen, but the whole _reason_
   for this commit is that udev is currently doing something horribly
   horribly wrong, so ...

Link: https://lore.kernel.org/all/ZEGopJ8VAYnE7LQ2@bombadil.infradead.org/ [1]
Link: https://lore.kernel.org/all/23bd0ce6-ef78-1cd8-1f21-0e706a00424a@suse.com/ [2]
Link: https://lore.kernel.org/lkml/ZG%2Fa+nrt4%2FAAUi5z@bombadil.infradead.org/ [3]
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Petr Pavlu <petr.pavlu@suse.com>
Tested-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull vfs fixes from Christian Brauner:

 - During the acl rework we merged this cycle the generic_listxattr()
   helper had to be modified in a way that in principle it would allow
   for POSIX ACLs to be reported. At least that was the impression we
   had initially. Because before the acl rework POSIX ACLs would be
   reported if the filesystem did have POSIX ACL xattr handlers in
   sb->s_xattr. That logic changed and now we can simply check whether
   the superblock has SB_POSIXACL set and if the inode has
   inode->i_{default_}acl set report the appropriate POSIX ACL name.

   However, we didn't realize that generic_listxattr() was only ever
   used by two filesystems. Both of them don't support POSIX ACLs via
   sb->s_xattr handlers and so never reported POSIX ACLs via
   generic_listxattr() even if they raised SB_POSIXACL and did contain
   inodes which had acls set. The example here is nfs4.

   As a result, generic_listxattr() suddenly started reporting POSIX
   ACLs when it wouldn't have before. Since SB_POSIXACL implies that the
   umask isn't stripped in the VFS nfs4 can't just drop SB_POSIXACL from
   the superblock as it would also alter umask handling for them.

   So just have generic_listxattr() not report POSIX ACLs as it never
   did anyway. It's documented as such.

 - Our SB_* flags currently use a signed integer and we shift the last
   bit causing UBSAN to complain about undefined behavior. Switch to
   using unsigned. While the original patch used an explicit unsigned
   bitshift it's now pretty common to rely on the BIT() macro in a lot
   of headers nowadays. So the patch has been adjusted to use that.

 - Add Namjae as ntfs reviewer. They're already active this cycle so
   let's make it explicit right now.

* tag 'vfs/v6.4-rc3/misc.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  ntfs: Add myself as a reviewer
  fs: don't call posix_acl_listxattr in generic_listxattr
  fs: fix undefined behavior in bit shift for SB_NOUSER