Pull drm fixes from Dave Airlie:
 "Weekly fixes, msm and xe are the two main ones, with a bunch of
  scattered fixes including a largish revert in mgag200, then amdgpu,
  vmwgfx and scattering of other minor ones.

  All seems pretty regular.

  msm:
   - Display:
      - move CRTC resource assignment to atomic_check otherwise to make
        consecutive calls to atomic_check() consistent
      - fix rounding / sign-extension issues with pclk calculation in
        case of DSC
      - cleanups to drop incorrect null checks in dpu snapshots
      - fix to use kvzalloc in dpu snapshot to avoid allocation issues
        in heavily loaded system cases
      - Fix to not program merge_3d block if dual LM is not being used
      - Fix to not flush merge_3d block if its not enabled otherwise
        this leads to false timeouts
   - GPU:
      - a7xx: add a fence wait before SMMU table update

  xe:
   - New workaround to Xe2 (Aradhya)
   - Fix unbalanced rpm put (Matthew Auld)
   - Remove fragile lock optimization (Matthew Brost)
   - Fix job release, delegating it to the drm scheduler (Matthew Brost)
   - Fix timestamp bit width for Xe2 (Lucas)
   - Fix external BO's dma-resv usag (Matthew Brost)
   - Fix returning success for timeout in wait_token (Nirmoy)
   - Initialize fence to avoid it being detected as signaled (Matthew
     Auld)
   - Improve cache flush for BMG (Matthew Auld)
   - Don't allow hflip for tile4 framebuffer on Xe2 (Juha-Pekka)

  amdgpu:
   - SR-IOV fix
   - CS chunk handling fix
   - MES fixes
   - SMU13 fixes

  amdkfd:
   - VRAM usage reporting fix

  radeon:
   - Fix possible_clones handling

  i915:
   - Two DP bandwidth related MST fixes

  ast:
   - Clear EDID on unplugged connectors

  host1x:
   - Fix boot on Tegra186
   - Set DMA parameters

  mgag200:
   - Revert VBLANK support

  panel:
   - himax-hx83192: Adjust power and gamma

  qaic:
   - Sgtable loop fixes

  vmwgfx:
   - Limit display layout allocatino size
   - Handle allocation errors in connector checks
   - Clean up KMS code for 2d-only setup
   - Report surface-check errors correctly
   - Remove NULL test around kvfree()"

* tag 'drm-fixes-2024-10-18' of https://gitlab.freedesktop.org/drm/kernel: (45 commits)
  drm/ast: vga: Clear EDID if no display is connected
  drm/ast: sil164: Clear EDID if no display is connected
  Revert "drm/mgag200: Add vblank support"
  drm/amdgpu/swsmu: default to fullscreen 3D profile for dGPUs
  drm/i915/display: Don't allow tile4 framebuffer to do hflip on display20 or greater
  drm/xe/bmg: improve cache flushing behaviour
  drm/xe/xe_sync: initialise ufence.signalled
  drm/xe/ufence: ufence can be signaled right after wait_woken
  drm/xe: Use bookkeep slots for external BO's in exec IOCTL
  drm/xe/query: Increase timestamp width
  drm/xe: Don't free job in TDR
  drm/xe: Take job list lock in xe_sched_add_pending_job
  drm/xe: fix unbalanced rpm put() with declare_wedged()
  drm/xe: fix unbalanced rpm put() with fence_fini()
  drm/xe/xe2lpg: Extend Wa_15016589081 for xe2lpg
  drm/i915/dp_mst: Don't require DSC hblank quirk for a non-DSC compatible mode
  drm/i915/dp_mst: Handle error during DSC BW overhead/slice calculation
  drm/msm/a6xx+: Insert a fence wait before SMMU table update
  drm/msm/dpu: don't always program merge_3d block
  drm/msm/dpu: Don't always set merge_3d pending flush
  ...

The lockdep asserts for the new follow_pfnmap() API "knows" that a
pfnmap always has a vma->vm_file, since that's the only way to create
such a mapping.

And that's actually true for all the normal cases.  But not for the mmap
failure case, where the incomplete mapping is torn down and we have
cleared vma->vm_file because the failure occured before the file was
linked to the vma.

So this codepath does actually need to check for vm_file being NULL.
Reported-by: Jann Horn <jannh@google.com>
Fixes: 6da8e963 ("mm: new follow_pfnmap API")
Cc: Peter Xu <peterx@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull iommu fixes from Joerg Roedel:
 "ARM-SMMU fixes from Will Deacon:

   - Clarify warning message when failing to disable the MMU-500
     prefetcher

   - Fix undefined behaviour in calculation of L1 stream-table index
     when 32-bit StreamIDs are implemented

   - Replace a rogue comma with a semicolon

  Intel VT-d fix from Lu Baolu:

   - Fix incorrect pci_for_each_dma_alias() for non-PCI devices"

* tag 'iommu-fixes-v6.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
  iommu/vt-d: Fix incorrect pci_for_each_dma_alias() for non-PCI devices
  iommu/arm-smmu-v3: Convert comma to semicolon
  iommu/arm-smmu-v3: Fix last_sid_idx calculation for sid_bits==32
  iommu/arm-smmu: Clarify MMU-500 CPRE workaround

Pull powerpc fix from Madhavan Srinivasan:

 - To prevent possible memory leak, free "name" on error in
   opal_event_init()

Thanks to Michael Ellerman and 2639161967.

* tag 'powerpc-6.12-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv: Free name on error in opal_event_init()

Pull s390 fixes from Heiko Carstens:

 - Fix PCI error recovery by handling error events correctly

 - Fix CCA crypto card behavior within protected execution environment

 - Two KVM commits which fix virtual vs physical address handling bugs
   in KVM pfault handling

 - Fix return code handling in pckmo_key2protkey()

 - Deactivate sclp console as late as possible so that outstanding
   messages appear on the console instead of being dropped on reboot

 - Convert newlines to CRLF instead of LFCR for the sclp vt220 driver,
   as required by the vt220 specification

 - Initialize also psw mask in perf_arch_fetch_caller_regs() to make
   sure that user_mode(regs) will return false

 - Update defconfigs

* tag 's390-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: Update defconfigs
  s390: Initialize psw mask in perf_arch_fetch_caller_regs()
  s390/sclp_vt220: Convert newlines to CRLF instead of LFCR
  s390/sclp: Deactivate sclp after all its users
  s390/pkey_pckmo: Return with success for valid protected key types
  KVM: s390: Change virtual to physical address access in diag 0x258 handler
  KVM: s390: gaccess: Check if guest address is in memslot
  s390/ap: Fix CCA crypto card behavior within protected execution environment
  s390/pci: Handle PCI error codes other than 0x3a

Driver Changes:
- New workaround to Xe2 (Aradhya)
- Fix unbalanced rpm put (Matthew Auld)
- Remove fragile lock optimization (Matthew Brost)
- Fix job release, delegating it to the drm scheduler (Matthew Brost)
- Fix timestamp bit width for Xe2 (Lucas)
- Fix external BO's dma-resv usag (Matthew Brost)
- Fix returning success for timeout in wait_token (Nirmoy)
- Initialize fence to avoid it being detected as signaled (Matthew Auld)
- Improve cache flush for BMG (Matthew Auld)
- Don't allow hflip for tile4 framebuffer on Xe2 (Juha-Pekka)
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/jkldrex5733ldxrla75b4ayvhujjhw2kccmasl5rotoufoacj4@pkvlrrv4orc7

Pull x86 IBPB fixes from Borislav Petkov:
 "This fixes the IBPB implementation of older AMDs (< gen4) that do not
  flush the RSB (Return Address Stack) so you can still do some leaking
  when using a "=ibpb" mitigation for Retbleed or SRSO. Fix it by doing
  the flushing in software on those generations.

  IBPB is not the default setting so this is not likely to affect
  anybody in practice"

* tag 'x86_bugs_post_ibpb' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/bugs: Do not use UNTRAIN_RET with IBPB on entry
  x86/bugs: Skip RSB fill at VMEXIT
  x86/entry: Have entry_ibpb() invalidate return predictions
  x86/cpufeatures: Add a IBPB_NO_RET BUG flag
  x86/cpufeatures: Define X86_FEATURE_AMD_IBPB_RET

Merge tag 'mm-hotfixes-stable-2024-10-17-16-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "28 hotfixes. 13 are cc:stable. 23 are MM.

  It is the usual shower of unrelated singletons - please see the
  individual changelogs for details"

* tag 'mm-hotfixes-stable-2024-10-17-16-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (28 commits)
  maple_tree: add regression test for spanning store bug
  maple_tree: correct tree corruption on spanning store
  mm/mglru: only clear kswapd_failures if reclaimable
  mm/swapfile: skip HugeTLB pages for unuse_vma
  selftests: mm: fix the incorrect usage() info of khugepaged
  MAINTAINERS: add Jann as memory mapping/VMA reviewer
  mm: swap: prevent possible data-race in __try_to_reclaim_swap
  mm: khugepaged: fix the incorrect statistics when collapsing large file folios
  MAINTAINERS: kasan, kcov: add bugzilla links
  mm: don't install PMD mappings when THPs are disabled by the hw/process/vma
  mm: huge_memory: add vma_thp_disabled() and thp_disabled_by_hw()
  Docs/damon/maintainer-profile: update deprecated awslabs GitHub URLs
  Docs/damon/maintainer-profile: add missing '_' suffixes for external web links
  maple_tree: check for MA_STATE_BULK on setting wr_rebalance
  mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point
  mm/damon/tests/sysfs-kunit.h: fix memory leak in damon_sysfs_test_add_targets()
  mm: remove unused stub for can_swapin_thp()
  mailmap: add an entry for Andy Chiu
  MAINTAINERS: add memory mapping/VMA co-maintainers
  fs/proc: fix build with GCC 15 due to -Werror=unterminated-string-initialization
  ...

Pull clk fixes from Stephen Boyd:
 "Two clk driver fixes and a unit test fix:

   - Terminate the of_device_id table in the Samsung exynosautov920 clk
     driver so that device matching logic doesn't run off the end of the
     array into other memory and break matching for any kernel with this
     driver loaded

   - Properly limit the max clk ID in the Rockchip clk driver

   - Use clk kunit helpers in the clk tests so that memory isn't leaked
     after the test concludes"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: test: Fix some memory leaks
  clk: rockchip: fix finding of maximum clock ID
  clk: samsung: Fix out-of-bound access of of_match_node()

Merge tag 'drm-misc-fixes-2024-10-17' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes

Short summary of fixes pull:

ast:
- Clear EDID on unplugged connectors

host1x:
- Fix boot on Tegra186
- Set DMA parameters

mgag200:
- Revert VBLANK support

panel:
- himax-hx83192: Adjust power and gamma

qaic:
- Sgtable loop fixes

vmwgfx:
- Limit display layout allocatino size
- Handle allocation errors in connector checks
- Clean up KMS code for 2d-only setup
- Report surface-check errors correctly
- Remove NULL test around kvfree()
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241017115516.GA196624@linux.fritz.box

Merge tag 'drm-intel-fixes-2024-10-17' of https://gitlab.freedesktop.org/drm/i915/kernel into drm-fixes

- Two DP bandwidth related MST fixes
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ZxDLdML9Dwqkb1AW@jlahtine-mobl.ger.corp.intel.com

Merge tag 'amd-drm-fixes-6.12-2024-10-16' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes

amd-drm-fixes-6.12-2024-10-16:

amdgpu:
- SR-IOV fix
- CS chunk handling fix
- MES fixes
- SMU13 fixes

amdkfd:
- VRAM usage reporting fix

radeon:
- Fix possible_clones handling
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241016200514.3520286-1-alexander.deucher@amd.com

Pull arm64 fixes from Will Deacon:

 - Disable software tag-based KASAN when compiling with GCC, as
   functions are incorrectly instrumented leading to a crash early
   during boot

 - Fix pkey configuration for kernel threads when POE is enabled

 - Fix invalid memory accesses in uprobes when targetting load-literal
   instructions

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  kasan: Disable Software Tag-Based KASAN with GCC
  Documentation/protection-keys: add AArch64 to documentation
  arm64: set POR_EL0 for kernel threads
  arm64: probes: Fix uprobes for big-endian kernels
  arm64: probes: Fix simulate_ldr*_literal()
  arm64: probes: Remove broken LDR (literal) uprobe support

Pull SoC fixes from Arnd Bergmann:
 "Most of the fixes this time are for platform specific drivers,
  addressing issues found through build testing on freescale, ep93xx,
  starfive, and npcm platforms, as as well as the ffa firmware.

  The fixes for the scmi firmware driver address compatibility problems
  found on broadcom machines.

  There are only two devicetree fixes, addressing incorrect in
  configuration on broadcom and marvell machines.

  The changes to the Documentation and MAINTAINERS files are for
  clarification only"

* tag 'arm-fixes-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  firmware: arm_ffa: Avoid string-fortify warning caused by memcpy()
  firmware: arm_scmi: Queue in scmi layer for mailbox implementation
  firmware: arm_ffa: Avoid string-fortify warning in export_uuid()
  firmware: arm_scmi: Give SMC transport precedence over mailbox
  firmware: arm_scmi: Fix the double free in scmi_debugfs_common_setup()
  Documentation/process: maintainer-soc: clarify submitting patches
  dmaengine: cirrus: check that output may be truncated
  dmaengine: cirrus: ERR_CAST() ioremap error
  MAINTAINERS: use the canonical soc mailing list address and mark it as L:
  ARM: dts: bcm2837-rpi-cm3-io3: Fix HDMI hpd-gpio pin
  arm64: dts: marvell: cn9130-sr-som: fix cp0 mdio pin numbers
  soc: fsl: cpm1: qmc: Fix unused data compilation warning
  soc: fsl: cpm1: qmc: Do not use IS_ERR_VALUE() on error pointers
  reset: starfive: jh71x0: Fix accessing the empty member on JH7110 SoC
  reset: npcm: convert comma to semicolon

Pull sound fixes from Takashi Iwai:
 "A collection of small fixes, nothing really stands out:

   - Usual HD-audio quirks / device-specific fixes

   - Kconfig dependency fix for UM

   - A series of minor fixes for SoundWire

   - Updates of USB-audio LINE6 contact address"

* tag 'sound-6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda/conexant - Use cached pin control for Node 0x1d on HP EliteOne 1000 G2
  ALSA/hda: intel-sdw-acpi: add support for sdw-manager-list property read
  ALSA/hda: intel-sdw-acpi: simplify sdw-master-count property read
  ALSA/hda: intel-sdw-acpi: fetch fwnode once in sdw_intel_scan_controller()
  ALSA/hda: intel-sdw-acpi: cleanup sdw_intel_scan_controller
  ALSA: hda/tas2781: Add new quirk for Lenovo, ASUS, Dell projects
  ALSA: scarlett2: Add error check after retrieving PEQ filter values
  ALSA: hda/cs8409: Fix possible NULL dereference
  sound: Make CONFIG_SND depend on INDIRECT_IOMEM instead of UML
  ALSA: line6: update contact information
  ALSA: usb-audio: Fix NULL pointer deref in snd_usb_power_domain_set()
  ALSA: hda/conexant - Fix audio routing for HP EliteOne 1000 G2
  ALSA: hda: Sound support for HP Spectre x360 16 inch model 2024

Pull networking fixes from Paolo Abeni:
 "Current release - new code bugs:

   - eth: mlx5: HWS, don't destroy more bwc queue locks than allocated

  Previous releases - regressions:

   - ipv4: give an IPv4 dev to blackhole_netdev

   - udp: compute L4 checksum as usual when not segmenting the skb

   - tcp/dccp: don't use timer_pending() in reqsk_queue_unlink().

   - eth: mlx5e: don't call cleanup on profile rollback failure

   - eth: microchip: vcap api: fix memory leaks in
     vcap_api_encode_rule_test()

   - eth: enetc: disable Tx BD rings after they are empty

   - eth: macb: avoid 20s boot delay by skipping MDIO bus registration
     for fixed-link PHY

  Previous releases - always broken:

   - posix-clock: fix missing timespec64 check in pc_clock_settime()

   - genetlink: hold RCU in genlmsg_mcast()

   - mptcp: prevent MPC handshake on port-based signal endpoints

   - eth: vmxnet3: fix packet corruption in vmxnet3_xdp_xmit_frame

   - eth: stmmac: dwmac-tegra: fix link bring-up sequence

   - eth: bcmasp: fix potential memory leak in bcmasp_xmit()

  Misc:

   - add Andrew Lunn as a co-maintainer of all networking drivers"

* tag 'net-6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (47 commits)
  net/mlx5e: Don't call cleanup on profile rollback failure
  net/mlx5: Unregister notifier on eswitch init failure
  net/mlx5: Fix command bitmask initialization
  net/mlx5: Check for invalid vector index on EQ creation
  net/mlx5: HWS, use lock classes for bwc locks
  net/mlx5: HWS, don't destroy more bwc queue locks than allocated
  net/mlx5: HWS, fixed double free in error flow of definer layout
  net/mlx5: HWS, removed wrong access to a number of rules variable
  mptcp: pm: fix UaF read in mptcp_pm_nl_rm_addr_or_subflow
  net: ethernet: mtk_eth_soc: fix memory corruption during fq dma init
  vmxnet3: Fix packet corruption in vmxnet3_xdp_xmit_frame
  net: dsa: vsc73xx: fix reception from VLAN-unaware bridges
  net: ravb: Only advertise Rx/Tx timestamps if hardware supports it
  net: microchip: vcap api: Fix memory leaks in vcap_api_encode_rule_test()
  net: phy: mdio-bcm-unimac: Add BCM6846 support
  dt-bindings: net: brcm,unimac-mdio: Add bcm6846-mdio
  udp: Compute L4 checksum as usual when not segmenting the skb
  genetlink: hold RCU in genlmsg_mcast()
  net: dsa: mv88e6xxx: Fix the max_vid definition for the MV88E6361
  tcp/dccp: Don't use timer_pending() in reqsk_queue_unlink().
  ...

Add a regression test to assert that, when performing a spanning store
which consumes the entirety of the rightmost right leaf node does not
result in maple tree corruption when doing so.

This achieves this by building a test tree of 3 levels and establishing a
store which ultimately results in a spanned store of this nature.

Link: https://lkml.kernel.org/r/30cdc101a700d16e03ba2f9aa5d83f2efa894168.1728314403.git.lorenzo.stoakes@oracle.comSigned-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Bert Karwatzki <spasswolf@web.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "maple_tree: correct tree corruption on spanning store", v3.

There has been a nasty yet subtle maple tree corruption bug that appears
to have been in existence since the inception of the algorithm.

This bug seems far more likely to happen since commit f8d112a4
("mm/mmap: avoid zeroing vma tree in mmap_region()"), which is the point
at which reports started to be submitted concerning this bug.

We were made definitely aware of the bug thanks to the kind efforts of
Bert Karwatzki who helped enormously in my being able to track this down
and identify the cause of it.

The bug arises when an attempt is made to perform a spanning store across
two leaf nodes, where the right leaf node is the rightmost child of the
shared parent, AND the store completely consumes the right-mode node.

This results in mas_wr_spanning_store() mitakenly duplicating the new and
existing entries at the maximum pivot within the range, and thus maple
tree corruption.

The fix patch corrects this by detecting this scenario and disallowing the
mistaken duplicate copy.

The fix patch commit message goes into great detail as to how this occurs.

This series also includes a test which reliably reproduces the issue, and
asserts that the fix works correctly.

Bert has kindly tested the fix and confirmed it resolved his issues.  Also
Mikhail Gavrilov kindly reported what appears to be precisely the same
bug, which this fix should also resolve.


This patch (of 2):

There has been a subtle bug present in the maple tree implementation from
its inception.

This arises from how stores are performed - when a store occurs, it will
overwrite overlapping ranges and adjust the tree as necessary to
accommodate this.

A range may always ultimately span two leaf nodes.  In this instance we
walk the two leaf nodes, determine which elements are not overwritten to
the left and to the right of the start and end of the ranges respectively
and then rebalance the tree to contain these entries and the newly
inserted one.

This kind of store is dubbed a 'spanning store' and is implemented by
mas_wr_spanning_store().

In order to reach this stage, mas_store_gfp() invokes
mas_wr_preallocate(), mas_wr_store_type() and mas_wr_walk() in turn to
walk the tree and update the object (mas) to traverse to the location
where the write should be performed, determining its store type.

When a spanning store is required, this function returns false stopping at
the parent node which contains the target range, and mas_wr_store_type()
marks the mas->store_type as wr_spanning_store to denote this fact.

When we go to perform the store in mas_wr_spanning_store(), we first
determine the elements AFTER the END of the range we wish to store (that
is, to the right of the entry to be inserted) - we do this by walking to
the NEXT pivot in the tree (i.e.  r_mas.last + 1), starting at the node we
have just determined contains the range over which we intend to write.

We then turn our attention to the entries to the left of the entry we are
inserting, whose state is represented by l_mas, and copy these into a 'big
node', which is a special node which contains enough slots to contain two
leaf node's worth of data.

We then copy the entry we wish to store immediately after this - the copy
and the insertion of the new entry is performed by mas_store_b_node().

After this we copy the elements to the right of the end of the range which
we are inserting, if we have not exceeded the length of the node (i.e. 
r_mas.offset <= r_mas.end).

Herein lies the bug - under very specific circumstances, this logic can
break and corrupt the maple tree.

Consider the following tree:

Height
  0                             Root Node
                                 /      \
                 pivot = 0xffff /        \ pivot = ULONG_MAX
                               /          \
  1                       A [-----]       ...
                             /   \
             pivot = 0x4fff /     \ pivot = 0xffff
                           /       \
  2 (LEAVES)          B [-----]  [-----] C
                                      ^--- Last pivot 0xffff.

Now imagine we wish to store an entry in the range [0x4000, 0xffff] (note
that all ranges expressed in maple tree code are inclusive):

1. mas_store_gfp() descends the tree, finds node A at <=0xffff, then
   determines that this is a spanning store across nodes B and C. The mas
   state is set such that the current node from which we traverse further
   is node A.

2. In mas_wr_spanning_store() we try to find elements to the right of pivot
   0xffff by searching for an index of 0x10000:

    - mas_wr_walk_index() invokes mas_wr_walk_descend() and
      mas_wr_node_walk() in turn.

        - mas_wr_node_walk() loops over entries in node A until EITHER it
          finds an entry whose pivot equals or exceeds 0x10000 OR it
          reaches the final entry.

        - Since no entry has a pivot equal to or exceeding 0x10000, pivot
          0xffff is selected, leading to node C.

    - mas_wr_walk_traverse() resets the mas state to traverse node C. We
      loop around and invoke mas_wr_walk_descend() and mas_wr_node_walk()
      in turn once again.

         - Again, we reach the last entry in node C, which has a pivot of
           0xffff.

3. We then copy the elements to the left of 0x4000 in node B to the big
   node via mas_store_b_node(), and insert the new [0x4000, 0xffff] entry
   too.

4. We determine whether we have any entries to copy from the right of the
   end of the range via - and with r_mas set up at the entry at pivot
   0xffff, r_mas.offset <= r_mas.end, and then we DUPLICATE the entry at
   pivot 0xffff.

5. BUG! The maple tree is corrupted with a duplicate entry.

This requires a very specific set of circumstances - we must be spanning
the last element in a leaf node, which is the last element in the parent
node.

spanning store across two leaf nodes with a range that ends at that shared
pivot.

A potential solution to this problem would simply be to reset the walk
each time we traverse r_mas, however given the rarity of this situation it
seems that would be rather inefficient.

Instead, this patch detects if the right hand node is populated, i.e.  has
anything we need to copy.

We do so by only copying elements from the right of the entry being
inserted when the maximum value present exceeds the last, rather than
basing this on offset position.

The patch also updates some comments and eliminates the unused bool return
value in mas_wr_walk_index().

The work performed in commit f8d112a4 ("mm/mmap: avoid zeroing vma
tree in mmap_region()") seems to have made the probability of this event
much more likely, which is the point at which reports started to be
submitted concerning this bug.

The motivation for this change arose from Bert Karwatzki's report of
encountering mm instability after the release of kernel v6.12-rc1 which,
after the use of CONFIG_DEBUG_VM_MAPLE_TREE and similar configuration
options, was identified as maple tree corruption.

After Bert very generously provided his time and ability to reproduce this
event consistently, I was able to finally identify that the issue
discussed in this commit message was occurring for him.

Link: https://lkml.kernel.org/r/cover.1728314402.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/48b349a2a0f7c76e18772712d0997a5e12ab0a3b.1728314403.git.lorenzo.stoakes@oracle.com
Fixes: 54a611b6 ("Maple Tree: add new data structure")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Bert Karwatzki <spasswolf@web.de>
Closes: https://lore.kernel.org/all/20241001023402.3374-1-spasswolf@web.de/Tested-by: Bert Karwatzki <spasswolf@web.de>
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Closes: https://lore.kernel.org/all/CABXGCsOPwuoNOqSMmAvWO2Fz4TEmPnjFj-b7iF+XFRu1h7-+Dg@mail.gmail.com/Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Tariq Toukan says:

====================
mlx5 misc fixes 2024-10-15

This patchset provides misc bug fixes from the team to the mlx5 core and
Eth drivers.

Series generated against:
commit 174714f0 ("selftests: drivers: net: fix name not defined")
====================

Link: https://patch.msgid.link/20241015093208.197603-1-tariqt@nvidia.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

When profile rollback fails in mlx5e_netdev_change_profile, the netdev
profile var is left set to NULL. Avoid a crash when unloading the driver
by not calling profile->cleanup in such a case.

This was encountered while testing, with the original trigger that
the wq rescuer thread creation got interrupted (presumably due to
Ctrl+C-ing modprobe), which gets converted to ENOMEM (-12) by
mlx5e_priv_init, the profile rollback also fails for the same reason
(signal still active) so the profile is left as NULL, leading to a crash
later in _mlx5e_remove.

 [  732.473932] mlx5_core 0000:08:00.1: E-Switch: Unload vfs: mode(OFFLOADS), nvfs(2), necvfs(0), active vports(2)
 [  734.525513] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR
 [  734.557372] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12
 [  734.559187] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: new profile init failed, -12
 [  734.560153] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR
 [  734.589378] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12
 [  734.591136] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: failed to rollback to orig profile, -12
 [  745.537492] BUG: kernel NULL pointer dereference, address: 0000000000000008
 [  745.538222] #PF: supervisor read access in kernel mode
<snipped>
 [  745.551290] Call Trace:
 [  745.551590]  <TASK>
 [  745.551866]  ? __die+0x20/0x60
 [  745.552218]  ? page_fault_oops+0x150/0x400
 [  745.555307]  ? exc_page_fault+0x79/0x240
 [  745.555729]  ? asm_exc_page_fault+0x22/0x30
 [  745.556166]  ? mlx5e_remove+0x6b/0xb0 [mlx5_core]
 [  745.556698]  auxiliary_bus_remove+0x18/0x30
 [  745.557134]  device_release_driver_internal+0x1df/0x240
 [  745.557654]  bus_remove_device+0xd7/0x140
 [  745.558075]  device_del+0x15b/0x3c0
 [  745.558456]  mlx5_rescan_drivers_locked.part.0+0xb1/0x2f0 [mlx5_core]
 [  745.559112]  mlx5_unregister_device+0x34/0x50 [mlx5_core]
 [  745.559686]  mlx5_uninit_one+0x46/0xf0 [mlx5_core]
 [  745.560203]  remove_one+0x4e/0xd0 [mlx5_core]
 [  745.560694]  pci_device_remove+0x39/0xa0
 [  745.561112]  device_release_driver_internal+0x1df/0x240
 [  745.561631]  driver_detach+0x47/0x90
 [  745.562022]  bus_remove_driver+0x84/0x100
 [  745.562444]  pci_unregister_driver+0x3b/0x90
 [  745.562890]  mlx5_cleanup+0xc/0x1b [mlx5_core]
 [  745.563415]  __x64_sys_delete_module+0x14d/0x2f0
 [  745.563886]  ? kmem_cache_free+0x1b0/0x460
 [  745.564313]  ? lockdep_hardirqs_on_prepare+0xe2/0x190
 [  745.564825]  do_syscall_64+0x6d/0x140
 [  745.565223]  entry_SYSCALL_64_after_hwframe+0x4b/0x53
 [  745.565725] RIP: 0033:0x7f1579b1288b

Fixes: 3ef14e46 ("net/mlx5e: Separate between netdev objects and mlx5e profiles initialization")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

It otherwise remains registered and a subsequent attempt at eswitch
enabling might trigger warnings of the sort:

[  682.589148] ------------[ cut here ]------------
[  682.590204] notifier callback eswitch_vport_event [mlx5_core] already registered
[  682.590256] WARNING: CPU: 13 PID: 2660 at kernel/notifier.c:31 notifier_chain_register+0x3e/0x90
[...snipped]
[  682.610052] Call Trace:
[  682.610369]  <TASK>
[  682.610663]  ? __warn+0x7c/0x110
[  682.611050]  ? notifier_chain_register+0x3e/0x90
[  682.611556]  ? report_bug+0x148/0x170
[  682.611977]  ? handle_bug+0x36/0x70
[  682.612384]  ? exc_invalid_op+0x13/0x60
[  682.612817]  ? asm_exc_invalid_op+0x16/0x20
[  682.613284]  ? notifier_chain_register+0x3e/0x90
[  682.613789]  atomic_notifier_chain_register+0x25/0x40
[  682.614322]  mlx5_eswitch_enable_locked+0x1d4/0x3b0 [mlx5_core]
[  682.614965]  mlx5_eswitch_enable+0xc9/0x100 [mlx5_core]
[  682.615551]  mlx5_device_enable_sriov+0x25/0x340 [mlx5_core]
[  682.616170]  mlx5_core_sriov_configure+0x50/0x170 [mlx5_core]
[  682.616789]  sriov_numvfs_store+0xb0/0x1b0
[  682.617248]  kernfs_fop_write_iter+0x117/0x1a0
[  682.617734]  vfs_write+0x231/0x3f0
[  682.618138]  ksys_write+0x63/0xe0
[  682.618536]  do_syscall_64+0x4c/0x100
[  682.618958]  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: 7624e58a ("net/mlx5: E-switch, register event handler before arming the event")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Command bitmask have a dedicated bit for MANAGE_PAGES command, this bit
isn't Initialize during command bitmask Initialization, only during
MANAGE_PAGES.

In addition, mlx5_cmd_trigger_completions() is trying to trigger
completion for MANAGE_PAGES command as well.

Hence, in case health error occurred before any MANAGE_PAGES command
have been invoke (for example, during mlx5_enable_hca()),
mlx5_cmd_trigger_completions() will try to trigger completion for
MANAGE_PAGES command, which will result in null-ptr-deref error.[1]

Fix it by Initialize command bitmask correctly.

While at it, re-write the code for better understanding.

[1]
BUG: KASAN: null-ptr-deref in mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core]
Write of size 4 at addr 0000000000000214 by task kworker/u96:2/12078
CPU: 10 PID: 12078 Comm: kworker/u96:2 Not tainted 6.9.0-rc2_for_upstream_debug_2024_04_07_19_01 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: mlx5_health0000:08:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core]
Call Trace:
 <TASK>
 dump_stack_lvl+0x7e/0xc0
 kasan_report+0xb9/0xf0
 kasan_check_range+0xec/0x190
 mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core]
 mlx5_cmd_flush+0x94/0x240 [mlx5_core]
 enter_error_state+0x6c/0xd0 [mlx5_core]
 mlx5_fw_fatal_reporter_err_work+0xf3/0x480 [mlx5_core]
 process_one_work+0x787/0x1490
 ? lockdep_hardirqs_on_prepare+0x400/0x400
 ? pwq_dec_nr_in_flight+0xda0/0xda0
 ? assign_work+0x168/0x240
 worker_thread+0x586/0xd30
 ? rescuer_thread+0xae0/0xae0
 kthread+0x2df/0x3b0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x2d/0x70
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork_asm+0x11/0x20
 </TASK>

Fixes: 9b98d395 ("net/mlx5: Start health poll at earlier stage of driver load")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Currently, mlx5 driver does not enforce vector index to be lower than
the maximum number of supported completion vectors when requesting a
new completion EQ. Thus, mlx5_comp_eqn_get() fails when trying to
acquire an IRQ with an improper vector index.

To prevent the case above, enforce that vector index value is
valid and lower than maximum in mlx5_comp_eqn_get() before handling the
request.

Fixes: f14c1a14 ("net/mlx5: Allocate completion EQs dynamically")
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

The HWS BWC API uses one lock per queue and usually acquires one of
them, except when doing changes which require locking all queues in
order. Naturally, lockdep isn't too happy about acquiring the same lock
class multiple times, so inform it that each queue lock is a different
class to avoid false positives.

Fixes: 2ca62599 ("net/mlx5: HWS, added send engine and context handling")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

hws_send_queues_bwc_locks_destroy destroyed more queue locks than
allocated, leading to memory corruption (occasionally) and warnings such
as DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock)) in __mutex_destroy because
sometimes, the 'mutex' being destroyed was random memory.
The severity of this problem is proportional to the number of queues
configured because the code overreaches beyond the end of the
bwc_send_queue_locks array by 2x its length.

Fix that by using the correct number of bwc queues.

Fixes: 2ca62599 ("net/mlx5: HWS, added send engine and context handling")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Fix error flow bug that could lead to double free of a buffer
during a failure to calculate a suitable definer layout.

Fixes: 74a778b4 ("net/mlx5: HWS, added definers handling")
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Itamar Gozlan <igozlan@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Removed wrong access to the num_of_rules field of the matcher.
This is a usual u32 variable, but the access was as if it was atomic.

This fixes the following CI warnings:
  mlx5hws_bwc.c:708:17: warning: large atomic operation may incur significant performance penalty;
  the access size (4 bytes) exceeds the max lock-free size (0 bytes) [-Watomic-alignment]

Fixes: 510f9f61 ("net/mlx5: HWS, added API and enabled HWS support")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409291101.6NdtMFVC-lkp@intel.com/Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Itamar Gozlan <igozlan@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Syzkaller reported this splat:

  ==================================================================
  BUG: KASAN: slab-use-after-free in mptcp_pm_nl_rm_addr_or_subflow+0xb44/0xcc0 net/mptcp/pm_netlink.c:881
  Read of size 4 at addr ffff8880569ac858 by task syz.1.2799/14662

  CPU: 0 UID: 0 PID: 14662 Comm: syz.1.2799 Not tainted 6.12.0-rc2-syzkaller-00307-g36c25451 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:94 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
   print_address_description mm/kasan/report.c:377 [inline]
   print_report+0xc3/0x620 mm/kasan/report.c:488
   kasan_report+0xd9/0x110 mm/kasan/report.c:601
   mptcp_pm_nl_rm_addr_or_subflow+0xb44/0xcc0 net/mptcp/pm_netlink.c:881
   mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:914 [inline]
   mptcp_nl_remove_id_zero_address+0x305/0x4a0 net/mptcp/pm_netlink.c:1572
   mptcp_pm_nl_del_addr_doit+0x5c9/0x770 net/mptcp/pm_netlink.c:1603
   genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
   genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
   genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
   netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2551
   genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
   netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
   netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
   netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
   sock_sendmsg_nosec net/socket.c:729 [inline]
   __sock_sendmsg net/socket.c:744 [inline]
   ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607
   ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661
   __sys_sendmsg+0x117/0x1f0 net/socket.c:2690
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf7fe4579
  Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
  RSP: 002b:00000000f574556c EFLAGS: 00000296 ORIG_RAX: 0000000000000172
  RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000020000140
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
   </TASK>

  Allocated by task 5387:
   kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
   kasan_save_track+0x14/0x30 mm/kasan/common.c:68
   poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
   __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
   kmalloc_noprof include/linux/slab.h:878 [inline]
   kzalloc_noprof include/linux/slab.h:1014 [inline]
   subflow_create_ctx+0x87/0x2a0 net/mptcp/subflow.c:1803
   subflow_ulp_init+0xc3/0x4d0 net/mptcp/subflow.c:1956
   __tcp_set_ulp net/ipv4/tcp_ulp.c:146 [inline]
   tcp_set_ulp+0x326/0x7f0 net/ipv4/tcp_ulp.c:167
   mptcp_subflow_create_socket+0x4ae/0x10a0 net/mptcp/subflow.c:1764
   __mptcp_subflow_connect+0x3cc/0x1490 net/mptcp/subflow.c:1592
   mptcp_pm_create_subflow_or_signal_addr+0xbda/0x23a0 net/mptcp/pm_netlink.c:642
   mptcp_pm_nl_fully_established net/mptcp/pm_netlink.c:650 [inline]
   mptcp_pm_nl_work+0x3a1/0x4f0 net/mptcp/pm_netlink.c:943
   mptcp_worker+0x15a/0x1240 net/mptcp/protocol.c:2777
   process_one_work+0x958/0x1b30 kernel/workqueue.c:3229
   process_scheduled_works kernel/workqueue.c:3310 [inline]
   worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
   kthread+0x2c1/0x3a0 kernel/kthread.c:389
   ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  Freed by task 113:
   kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
   kasan_save_track+0x14/0x30 mm/kasan/common.c:68
   kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
   poison_slab_object mm/kasan/common.c:247 [inline]
   __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
   kasan_slab_free include/linux/kasan.h:230 [inline]
   slab_free_hook mm/slub.c:2342 [inline]
   slab_free mm/slub.c:4579 [inline]
   kfree+0x14f/0x4b0 mm/slub.c:4727
   kvfree+0x47/0x50 mm/util.c:701
   kvfree_rcu_list+0xf5/0x2c0 kernel/rcu/tree.c:3423
   kvfree_rcu_drain_ready kernel/rcu/tree.c:3563 [inline]
   kfree_rcu_monitor+0x503/0x8b0 kernel/rcu/tree.c:3632
   kfree_rcu_shrink_scan+0x245/0x3a0 kernel/rcu/tree.c:3966
   do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
   shrink_slab+0x32b/0x12a0 mm/shrinker.c:662
   shrink_one+0x47e/0x7b0 mm/vmscan.c:4818
   shrink_many mm/vmscan.c:4879 [inline]
   lru_gen_shrink_node mm/vmscan.c:4957 [inline]
   shrink_node+0x2452/0x39d0 mm/vmscan.c:5937
   kswapd_shrink_node mm/vmscan.c:6765 [inline]
   balance_pgdat+0xc19/0x18f0 mm/vmscan.c:6957
   kswapd+0x5ea/0xbf0 mm/vmscan.c:7226
   kthread+0x2c1/0x3a0 kernel/kthread.c:389
   ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  Last potentially related work creation:
   kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
   __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541
   kvfree_call_rcu+0x74/0xbe0 kernel/rcu/tree.c:3810
   subflow_ulp_release+0x2ae/0x350 net/mptcp/subflow.c:2009
   tcp_cleanup_ulp+0x7c/0x130 net/ipv4/tcp_ulp.c:124
   tcp_v4_destroy_sock+0x1c5/0x6a0 net/ipv4/tcp_ipv4.c:2541
   inet_csk_destroy_sock+0x1a3/0x440 net/ipv4/inet_connection_sock.c:1293
   tcp_done+0x252/0x350 net/ipv4/tcp.c:4870
   tcp_rcv_state_process+0x379b/0x4f30 net/ipv4/tcp_input.c:6933
   tcp_v4_do_rcv+0x1ad/0xa90 net/ipv4/tcp_ipv4.c:1938
   sk_backlog_rcv include/net/sock.h:1115 [inline]
   __release_sock+0x31b/0x400 net/core/sock.c:3072
   __tcp_close+0x4f3/0xff0 net/ipv4/tcp.c:3142
   __mptcp_close_ssk+0x331/0x14d0 net/mptcp/protocol.c:2489
   mptcp_close_ssk net/mptcp/protocol.c:2543 [inline]
   mptcp_close_ssk+0x150/0x220 net/mptcp/protocol.c:2526
   mptcp_pm_nl_rm_addr_or_subflow+0x2be/0xcc0 net/mptcp/pm_netlink.c:878
   mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:914 [inline]
   mptcp_nl_remove_id_zero_address+0x305/0x4a0 net/mptcp/pm_netlink.c:1572
   mptcp_pm_nl_del_addr_doit+0x5c9/0x770 net/mptcp/pm_netlink.c:1603
   genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
   genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
   genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
   netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2551
   genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
   netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
   netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
   netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
   sock_sendmsg_nosec net/socket.c:729 [inline]
   __sock_sendmsg net/socket.c:744 [inline]
   ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607
   ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661
   __sys_sendmsg+0x117/0x1f0 net/socket.c:2690
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  The buggy address belongs to the object at ffff8880569ac800
   which belongs to the cache kmalloc-512 of size 512
  The buggy address is located 88 bytes inside of
   freed 512-byte region [ffff8880569ac800, ffff8880569aca00)

  The buggy address belongs to the physical page:
  page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x569ac
  head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
  flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff)
  page_type: f5(slab)
  raw: 04fff00000000040 ffff88801ac42c80 dead000000000100 dead000000000122
  raw: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000
  head: 04fff00000000040 ffff88801ac42c80 dead000000000100 dead000000000122
  head: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000
  head: 04fff00000000002 ffffea00015a6b01 ffffffffffffffff 0000000000000000
  head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: kasan: bad access detected
  page_owner tracks the page as allocated
  page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10238, tgid 10238 (kworker/u32:6), ts 597403252405, free_ts 597177952947
   set_page_owner include/linux/page_owner.h:32 [inline]
   post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1537
   prep_new_page mm/page_alloc.c:1545 [inline]
   get_page_from_freelist+0x101e/0x3070 mm/page_alloc.c:3457
   __alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4733
   alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
   alloc_slab_page mm/slub.c:2412 [inline]
   allocate_slab mm/slub.c:2578 [inline]
   new_slab+0x2ba/0x3f0 mm/slub.c:2631
   ___slab_alloc+0xd1d/0x16f0 mm/slub.c:3818
   __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
   __slab_alloc_node mm/slub.c:3961 [inline]
   slab_alloc_node mm/slub.c:4122 [inline]
   __kmalloc_cache_noprof+0x2c5/0x310 mm/slub.c:4290
   kmalloc_noprof include/linux/slab.h:878 [inline]
   kzalloc_noprof include/linux/slab.h:1014 [inline]
   mld_add_delrec net/ipv6/mcast.c:743 [inline]
   igmp6_leave_group net/ipv6/mcast.c:2625 [inline]
   igmp6_group_dropped+0x4ab/0xe40 net/ipv6/mcast.c:723
   __ipv6_dev_mc_dec+0x281/0x360 net/ipv6/mcast.c:979
   addrconf_leave_solict net/ipv6/addrconf.c:2253 [inline]
   __ipv6_ifa_notify+0x3f6/0xc30 net/ipv6/addrconf.c:6283
   addrconf_ifdown.isra.0+0xef9/0x1a20 net/ipv6/addrconf.c:3982
   addrconf_notify+0x220/0x19c0 net/ipv6/addrconf.c:3781
   notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
   call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996
   call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
   call_netdevice_notifiers net/core/dev.c:2048 [inline]
   dev_close_many+0x333/0x6a0 net/core/dev.c:1589
  page last free pid 13136 tgid 13136 stack trace:
   reset_page_owner include/linux/page_owner.h:25 [inline]
   free_pages_prepare mm/page_alloc.c:1108 [inline]
   free_unref_page+0x5f4/0xdc0 mm/page_alloc.c:2638
   stack_depot_save_flags+0x2da/0x900 lib/stackdepot.c:666
   kasan_save_stack+0x42/0x60 mm/kasan/common.c:48
   kasan_save_track+0x14/0x30 mm/kasan/common.c:68
   unpoison_slab_object mm/kasan/common.c:319 [inline]
   __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
   kasan_slab_alloc include/linux/kasan.h:247 [inline]
   slab_post_alloc_hook mm/slub.c:4085 [inline]
   slab_alloc_node mm/slub.c:4134 [inline]
   kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4141
   skb_clone+0x190/0x3f0 net/core/skbuff.c:2084
   do_one_broadcast net/netlink/af_netlink.c:1462 [inline]
   netlink_broadcast_filtered+0xb11/0xef0 net/netlink/af_netlink.c:1540
   netlink_broadcast+0x39/0x50 net/netlink/af_netlink.c:1564
   uevent_net_broadcast_untagged lib/kobject_uevent.c:331 [inline]
   kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline]
   kobject_uevent_env+0xacd/0x1670 lib/kobject_uevent.c:608
   device_del+0x623/0x9f0 drivers/base/core.c:3882
   snd_card_disconnect.part.0+0x58a/0x7c0 sound/core/init.c:546
   snd_card_disconnect+0x1f/0x30 sound/core/init.c:495
   snd_usx2y_disconnect+0xe9/0x1f0 sound/usb/usx2y/usbusx2y.c:417
   usb_unbind_interface+0x1e8/0x970 drivers/usb/core/driver.c:461
   device_remove drivers/base/dd.c:569 [inline]
   device_remove+0x122/0x170 drivers/base/dd.c:561

That's because 'subflow' is used just after 'mptcp_close_ssk(subflow)',
which will initiate the release of its memory. Even if it is very likely
the release and the re-utilisation will be done later on, it is of
course better to avoid any issues and read the content of 'subflow'
before closing it.

Fixes: 1c1f7213 ("mptcp: pm: only decrement add_addr_accepted for MPJ req")
Cc: stable@vger.kernel.org
Reported-by: syzbot+3c8b7a8e7df6a2a226ca@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/670d7337.050a0220.4cbc0.004f.GAE@google.comSigned-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20241015-net-mptcp-uaf-pm-rm-v1-1-c4ee5d987a64@kernel.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

The loop responsible for allocating up to MTK_FQ_DMA_LENGTH buffers must
only touch as many descriptors, otherwise it ends up corrupting unrelated
memory. Fix the loop iteration count accordingly.

Fixes: c57e5581 ("net: ethernet: mtk_eth_soc: handle dma buffer size soc specific")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20241015081755.31060-1-nbd@nbd.nameSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Andrew and Nikolay reported connectivity issues with Cilium's service
load-balancing in case of vmxnet3.

If a BPF program for native XDP adds an encapsulation header such as
IPIP and transmits the packet out the same interface, then in case
of vmxnet3 a corrupted packet is being sent and subsequently dropped
on the path.

vmxnet3_xdp_xmit_frame() which is called e.g. via vmxnet3_run_xdp()
through vmxnet3_xdp_xmit_back() calculates an incorrect DMA address:

  page = virt_to_page(xdpf->data);
  tbi->dma_addr = page_pool_get_dma_addr(page) +
                  VMXNET3_XDP_HEADROOM;
  dma_sync_single_for_device(&adapter->pdev->dev,
                             tbi->dma_addr, buf_size,
                             DMA_TO_DEVICE);

The above assumes a fixed offset (VMXNET3_XDP_HEADROOM), but the XDP
BPF program could have moved xdp->data. While the passed buf_size is
correct (xdpf->len), the dma_addr needs to have a dynamic offset which
can be calculated as xdpf->data - (void *)xdpf, that is, xdp->data -
xdp->data_hard_start.

Fixes: 54f00cce ("vmxnet3: Add XDP support.")
Reported-by: Andrew Sauber <andrew.sauber@isovalent.com>
Reported-by: Nikolay Nikolaev <nikolay.nikolaev@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Nikolay Nikolaev <nikolay.nikolaev@isovalent.com>
Acked-by: Anton Protopopov <aspsk@isovalent.com>
Cc: William Tu <witu@nvidia.com>
Cc: Ronak Doshi <ronak.doshi@broadcom.com>
Link: https://patch.msgid.link/a0888656d7f09028f9984498cc698bb5364d89fc.1728931137.git.daniel@iogearbox.netSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Fixes for v6.12

Display:
- move CRTC resource assignment to atomic_check otherwise to make
  consecutive calls to atomic_check() consistent
- fix rounding / sign-extension issues with pclk calculation in
  case of DSC
- cleanups to drop incorrect null checks in dpu snapshots
- fix to use kvzalloc in dpu snapshot to avoid allocation issues
  in heavily loaded system cases
- Fix to not program merge_3d block if dual LM is not being used
- Fix to not flush merge_3d block if its not enabled otherwise
  this leads to false timeouts

GPU:
- a7xx: add a fence wait before SMMU table update
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGsp3Zbd_H3FhHdRz9yCYA4wxX4SenpYRSk=Mx2d8GMSuQ@mail.gmail.com

lru_gen_shrink_node() unconditionally clears kswapd_failures, which can
prevent kswapd from sleeping and cause 100% kswapd cpu usage even when
kswapd repeatedly fails to make progress in reclaim.

Only clear kswap_failures in lru_gen_shrink_node() if reclaim makes some
progress, similar to shrink_node().

I happened to run into this problem in one of my tests recently.  It
requires a combination of several conditions: The allocator needs to
allocate a right amount of pages such that it can wake up kswapd
without itself being OOM killed; there is no memory for kswapd to
reclaim (My test disables swap and cleans page cache first); no other
process frees enough memory at the same time.

Link: https://lkml.kernel.org/r/20241014221211.832591-1-weixugc@google.com
Fixes: e4dde56c ("mm: multi-gen LRU: per-node lru_gen_folio lists")
Signed-off-by: Wei Xu <weixugc@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jan Alexander Steffens <heftig@archlinux.org>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

I got a bad pud error and lost a 1GB HugeTLB when calling swapoff.  The
problem can be reproduced by the following steps:

 1. Allocate an anonymous 1GB HugeTLB and some other anonymous memory.
 2. Swapout the above anonymous memory.
 3. run swapoff and we will get a bad pud error in kernel message:

  mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7)

We can tell that pud_clear_bad is called by pud_none_or_clear_bad in
unuse_pud_range() by ftrace.  And therefore the HugeTLB pages will never
be freed because we lost it from page table.  We can skip HugeTLB pages
for unuse_vma to fix it.

Link: https://lkml.kernel.org/r/20241015014521.570237-1-liushixin2@huawei.com
Fixes: 0fe6e20b ("hugetlb, rmap: add reverse mapping for hugepage")
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The mount option of tmpfs should be huge=advise, not madvise which is not
supported and may mislead the users.

Link: https://lkml.kernel.org/r/20241015020257.139235-1-sunnanyong@huawei.com
Fixes: 1b03d0d5 ("selftests/vm: add thp collapse file and tmpfs testing")
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Add myself as a reviewer for memory mapping / VMA code.  I will probably
only reply to patches sporadically, but hopefully this will help me keep
up with changes that look interesting security-wise.

Link: https://lkml.kernel.org/r/20241014-maintainers-mmap-reviewer-v1-1-50dce0514752@google.comSigned-off-by: Jann Horn <jannh@google.com>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

A report [1] was uploaded from syzbot.

In the previous commit 862590ac ("mm: swap: allow cache reclaim to
skip slot cache"), the __try_to_reclaim_swap() function reads offset and
folio->entry from folio without folio_lock protection.

In the currently reported KCSAN log, it is assumed that the actual
data-race will not occur because the calltrace that does WRITE already
obtains the folio_lock and then writes.

However, the existing __try_to_reclaim_swap() function was already
implemented to perform reads under folio_lock protection [1], and there is
a risk of a data-race occurring through a function other than the one
shown in the KCSAN log.

Therefore, I think it is appropriate to change
read operations for folio to be performed under folio_lock.

[1]

==================================================================
BUG: KCSAN: data-race in __delete_from_swap_cache / __try_to_reclaim_swap

write to 0xffffea0004c90328 of 8 bytes by task 5186 on cpu 0:
 __delete_from_swap_cache+0x1f0/0x290 mm/swap_state.c:163
 delete_from_swap_cache+0x72/0xe0 mm/swap_state.c:243
 folio_free_swap+0x1d8/0x1f0 mm/swapfile.c:1850
 free_swap_cache mm/swap_state.c:293 [inline]
 free_pages_and_swap_cache+0x1fc/0x410 mm/swap_state.c:325
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x2cf/0x440 mm/mmu_gather.c:373
 zap_pte_range mm/memory.c:1700 [inline]
 zap_pmd_range mm/memory.c:1739 [inline]
 zap_pud_range mm/memory.c:1768 [inline]
 zap_p4d_range mm/memory.c:1789 [inline]
 unmap_page_range+0x1f3c/0x22d0 mm/memory.c:1810
 unmap_single_vma+0x142/0x1d0 mm/memory.c:1856
 unmap_vmas+0x18d/0x2b0 mm/memory.c:1900
 exit_mmap+0x18a/0x690 mm/mmap.c:1864
 __mmput+0x28/0x1b0 kernel/fork.c:1347
 mmput+0x4c/0x60 kernel/fork.c:1369
 exit_mm+0xe4/0x190 kernel/exit.c:571
 do_exit+0x55e/0x17f0 kernel/exit.c:926
 do_group_exit+0x102/0x150 kernel/exit.c:1088
 get_signal+0xf2a/0x1070 kernel/signal.c:2917
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004c90328 of 8 bytes by task 5189 on cpu 1:
 __try_to_reclaim_swap+0x9d/0x510 mm/swapfile.c:198
 free_swap_and_cache_nr+0x45d/0x8a0 mm/swapfile.c:1915
 zap_pte_range mm/memory.c:1656 [inline]
 zap_pmd_range mm/memory.c:1739 [inline]
 zap_pud_range mm/memory.c:1768 [inline]
 zap_p4d_range mm/memory.c:1789 [inline]
 unmap_page_range+0xcf8/0x22d0 mm/memory.c:1810
 unmap_single_vma+0x142/0x1d0 mm/memory.c:1856
 unmap_vmas+0x18d/0x2b0 mm/memory.c:1900
 exit_mmap+0x18a/0x690 mm/mmap.c:1864
 __mmput+0x28/0x1b0 kernel/fork.c:1347
 mmput+0x4c/0x60 kernel/fork.c:1369
 exit_mm+0xe4/0x190 kernel/exit.c:571
 do_exit+0x55e/0x17f0 kernel/exit.c:926
 __do_sys_exit kernel/exit.c:1055 [inline]
 __se_sys_exit kernel/exit.c:1053 [inline]
 __x64_sys_exit+0x1f/0x20 kernel/exit.c:1053
 x64_sys_call+0x2d46/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:61
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000242 -> 0x0000000000000000

Link: https://lkml.kernel.org/r/20241007070623.23340-1-aha310510@gmail.com
Reported-by: syzbot+fa43f1b63e3aa6f66329@syzkaller.appspotmail.com
Fixes: 862590ac ("mm: swap: allow cache reclaim to skip slot cache")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Acked-by: Chris Li <chrisl@kernel.org>
Reviewed-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Khugepaged already supports collapsing file large folios (including shmem
mTHP) by commit 7de856ff ("mm: khugepaged: support shmem mTHP
collapse"), and the control parameters in khugepaged:
'khugepaged_max_ptes_swap' and 'khugepaged_max_ptes_none', still compare
based on PTE granularity to determine whether a file collapse is needed. 
However, the statistics for 'present' and 'swap' in
hpage_collapse_scan_file() do not take into account the large folios,
which may lead to incorrect judgments regarding the
khugepaged_max_ptes_swap/none parameters, resulting in unnecessary file
collapses.

To fix this issue, take into account the large folios' statistics for
'present' and 'swap' variables in the hpage_collapse_scan_file().

Link: https://lkml.kernel.org/r/c76305d96d12d030a1a346b50503d148364246d2.1728901391.git.baolin.wang@linux.alibaba.com
Fixes: 7de856ff ("mm: khugepaged: support shmem mTHP collapse")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Add links to the Bugzilla component that's used to track KASAN and KCOV
issues.

Link: https://lkml.kernel.org/r/20241012225524.117871-1-andrey.konovalov@linux.devSigned-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

We (or rather, readahead logic :) ) might be allocating a THP in the
pagecache and then try mapping it into a process that explicitly disabled
THP: we might end up installing PMD mappings.

This is a problem for s390x KVM, which explicitly remaps all PMD-mapped
THPs to be PTE-mapped in s390_enable_sie()->thp_split_mm(), before
starting the VM.

For example, starting a VM backed on a file system with large folios
supported makes the VM crash when the VM tries accessing such a mapping
using KVM.

Is it also a problem when the HW disabled THP using
TRANSPARENT_HUGEPAGE_UNSUPPORTED?  At least on x86 this would be the case
without X86_FEATURE_PSE.

In the future, we might be able to do better on s390x and only disallow
PMD mappings -- what s390x and likely TRANSPARENT_HUGEPAGE_UNSUPPORTED
really wants.  For now, fix it by essentially performing the same check as
would be done in __thp_vma_allowable_orders() or in shmem code, where this
works as expected, and disallow PMD mappings, making us fallback to PTE
mappings.

Link: https://lkml.kernel.org/r/20241011102445.934409-3-david@redhat.com
Fixes: 793917d9 ("mm/readahead: Add large folio readahead")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Leo Fu <bfu@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Cc: Thomas Huth <thuth@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "mm: don't install PMD mappings when THPs are disabled by the
hw/process/vma".

During testing, it was found that we can get PMD mappings in processes
where THP (and more precisely, PMD mappings) are supposed to be disabled. 
While it works as expected for anon+shmem, the pagecache is the
problematic bit.

For s390 KVM this currently means that a VM backed by a file located on
filesystem with large folio support can crash when KVM tries accessing the
problematic page, because the readahead logic might decide to use a
PMD-sized THP and faulting it into the page tables will install a PMD
mapping, something that s390 KVM cannot tolerate.

This might also be a problem with HW that does not support PMD mappings,
but I did not try reproducing it.

Fix it by respecting the ways to disable THPs when deciding whether we can
install a PMD mapping.  khugepaged should already be taking care of not
collapsing if THPs are effectively disabled for the hw/process/vma.


This patch (of 2):

Add vma_thp_disabled() and thp_disabled_by_hw() helpers to be shared by
shmem_allowable_huge_orders() and __thp_vma_allowable_orders().

[david@redhat.com: rename to vma_thp_disabled(), split out thp_disabled_by_hw() ]
Link: https://lkml.kernel.org/r/20241011102445.934409-2-david@redhat.com
Fixes: 793917d9 ("mm/readahead: Add large folio readahead")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Leo Fu <bfu@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Boqiao Fu <bfu@redhat.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>