Pull nfsd fix from Bruce Fields:
 "Just one fix for a NULL dereference if someone happens to read
  /proc/fs/nfsd/client/../state at the wrong moment"

* tag 'nfsd-5.8-2' of git://linux-nfs.org/~bfields/linux:
  nfsd4: fix NULL dereference in nfsd/clients display code

Merge misc fixes from Andrew Morton:
 "Subsystems affected by this patch series: mm/pagemap, mm/shmem,
  mm/hotfixes, mm/memcg, mm/hugetlb, mailmap, squashfs, scripts,
  io-mapping, MAINTAINERS, and gdb"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  scripts/gdb: fix lx-symbols 'gdb.error' while loading modules
  MAINTAINERS: add KCOV section
  io-mapping: indicate mapping failure
  scripts/decode_stacktrace: strip basepath from all paths
  squashfs: fix length field overlap check in metadata reading
  mailmap: add entry for Mike Rapoport
  khugepaged: fix null-pointer dereference due to race
  mm/hugetlb: avoid hardcoding while checking if cma is enabled
  mm: memcg/slab: fix memory leak at non-root kmem_cache destroy
  mm/memcg: fix refcount error while moving and swapping
  mm/memcontrol: fix OOPS inside mem_cgroup_get_nr_swap_pages()
  mm: initialize return of vm_insert_pages
  vfs/xattr: mm/shmem: kernfs: release simple xattr entry in a right way
  mm/mmap.c: close race between munmap() and expand_upwards()/downwards()

Pull xtensa csum regression fix from Al Viro:
 "Max Filippov caught a breakage introduced in xtensa this cycle
  by the csum_and_copy_..._user() series.

  Cut'n'paste from the wrong source - the check that belongs
  in csum_and_copy_to_user() ended up both there and in
  csum_and_copy_from_user()"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  xtensa: fix access check in csum_and_copy_from_user

Pull arm64 fix from Will Deacon:
 "Fix compat vDSO build flags for recent versions of clang to tell it
  where to find the assembler"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: vdso32: Fix '--prefix=' value for newer versions of clang

Merge tag 'for-5.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into master

Pull btrfs fixes from David Sterba:
 "A few resouce leak fixes from recent patches, all are stable material.

  The problems have been observed during testing or have a reproducer"

* tag 'for-5.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix mount failure caused by race with umount
  btrfs: fix page leaks after failure to lock page for delalloc
  btrfs: qgroup: fix data leak caused by race between writeback and truncate
  btrfs: fix double free on ulist after backref resolution failure

Merge tag 'zonefs-5.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs into master

Pull zonefs fixes from Damien Le Moal:
 "Two fixes, the first one to remove compilation warnings and the second
  to avoid potentially inefficient allocation of BIOs for direct writes
  into sequential zones"

* tag 'zonefs-5.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: count pages after truncating the iterator
  zonefs: Fix compilation warning

Pull io_uring fixes from Jens Axboe:

 - Fix discrepancy in how sqe->flags are treated for a few requests,
   this makes it consistent (Daniele)

 - Ensure that poll driven retry works with double waitqueue poll users

 - Fix a missing io_req_init_async() (Pavel)

* tag 'io_uring-5.8-2020-07-24' of git://git.kernel.dk/linux-block:
  io_uring: missed req_init_async() for IOSQE_ASYNC
  io_uring: always allow drain/link/hardlink/async sqe flags
  io_uring: ensure double poll additions work with both request types

Merge tag 'iommu-fix-v5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu into master

Pull iommu fix from Joerg Roedel:
 "Fix a NULL-ptr dereference in the QCOM IOMMU driver"

* tag 'iommu-fix-v5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/qcom: Use domain rather than dev as tlb cookie

Pull rdma fixes from Jason Gunthorpe:
 "One merge window regression, some corruption bugs in HNS and a few
  more syzkaller fixes:

   - Two long standing syzkaller races

   - Fix incorrect HW configuration in HNS

   - Restore accidentally dropped locking in IB CM

   - Fix ODP prefetch bug added in the big rework several versions ago"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/mlx5: Prevent prefetch from racing with implicit destruction
  RDMA/cm: Protect access to remote_sidr_table
  RDMA/core: Fix race in rdma_alloc_commit_uobject()
  RDMA/hns: Fix wrong PBL offset when VA is not aligned to PAGE_SIZE
  RDMA/hns: Fix wrong assignment of lp_pktn_ini in QPC
  RDMA/mlx5: Use xa_lock_irq when access to SRQ table

Merge tag 'for-5.8/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm into master

Pull device mapper fix from Mike Snitzer:
 "A stable fix for DM integrity target's integrity recalculation that
  gets skipped when resuming a device. This is a fix for a previous
  stable@ fix"

* tag 'for-5.8/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm integrity: fix integrity recalculation that is improperly skipped

Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux into master

Pull i2c fixes from Wolfram Sang:
 "Again some driver bugfixes and some documentation fixes"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: i2c-qcom-geni: Fix DMA transfer race
  i2c: rcar: always clear ICSAR to avoid side effects
  MAINTAINERS: i2c: at91: handover maintenance to Codrin Ciubotariu
  i2c: drop duplicated word in the header file
  i2c: cadence: Clear HOLD bit at correct time in Rx path
  Revert "i2c: cadence: Fix the hold bit setting"

Pull MMC fix from Ulf Hansson:
 "Fix clock divider calculation in the ASPEED SDHCI controller"

* tag 'mmc-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-of-aspeed: Fix clock divider calculation

Pull drm fixes from Dave Airlie:
 "Quiet fixes, I may have a single regression fix follow up to this for
  nouveau, but it might be next week, Ben was testing it a bit more .

  Otherwise two amdgpu fixes, one lima and one sun4i:

  amdgpu:
    - Fix crash when overclocking VegaM
    - Fix possible crash when editing dpm levels

  sun4i:
    - Fix inverted HPD result; fixes an earlier fix

  lima:
    - fix timeout during reset"

* tag 'drm-fixes-2020-07-24' of git://anongit.freedesktop.org/drm/drm:
  drm/amdgpu: Fix NULL dereference in dpm sysfs handlers
  drm/amd/powerplay: fix a crash when overclocking Vega M
  drm/lima: fix wait pp reset timeout
  drm: sun4i: hdmi: Fix inverted HPD result

Commit ed66f991 ("module: Refactor section attr into bin attribute")
removed the 'name' field from 'struct module_sect_attr' triggering the
following error when invoking lx-symbols:

  (gdb) lx-symbols
  loading vmlinux
  scanning for modules in linux/build
  loading @0xffffffffc014f000: linux/build/drivers/net/tun.ko
  Python Exception <class 'gdb.error'> There is no member named name.:
  Error occurred in Python: There is no member named name.

This patch fixes the issue taking the module name from the 'struct
attribute'.

Fixes: ed66f991 ("module: Refactor section attr into bin attribute")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Kieran Bingham <kbingham@kernel.org>
Link: http://lkml.kernel.org/r/20200722102239.313231-1-sgarzare@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

To link KCOV to the kasan-dev@ mailing list.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/5fa344db7ac4af2213049e5656c0f43d6ecaa379.1595331682.git.andreyknvl@google.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The !ATOMIC_IOMAP version of io_maping_init_wc will always return
success, even when the ioremap fails.

Since the ATOMIC_IOMAP version returns NULL when the init fails, and
callers check for a NULL return on error this is unexpected.

During a device probe, where the ioremap failed, a crash can look like
this:

    BUG: unable to handle page fault for address: 0000000000210000
     #PF: supervisor write access in kernel mode
     #PF: error_code(0x0002) - not-present page
     Oops: 0002 [#1] PREEMPT SMP
     CPU: 0 PID: 177 Comm:
     RIP: 0010:fill_page_dma [i915]
       gen8_ppgtt_create [i915]
       i915_ppgtt_create [i915]
       intel_gt_init [i915]
       i915_gem_init [i915]
       i915_driver_probe [i915]
       pci_device_probe
       really_probe
       driver_probe_device

The remap failure occurred much earlier in the probe.  If it had been
propagated, the driver would have exited with an error.

Return NULL on ioremap failure.

[akpm@linux-foundation.org: detect ioremap_wc() errors earlier]

Fixes: cafaf14a ("io-mapping: Always create a struct to hold metadata about the io-mapping")
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200721171936.81563-1-michael.j.ruhl@intel.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently the basepath is removed only from the beginning of the string.
When the symbol is inlined and there's multiple line outputs of
addr2line, only the first line would have basepath removed.

Change to remove the basepath prefix from all lines.

Fixes: 31013836 ("scripts/decode_stacktrace: match basepath using shell prefix operator, not regex")
Co-developed-by: Shik Chen <shik@chromium.org>
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Shik Chen <shik@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Nicolas Boichat <drinkcat@chromium.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Link: http://lkml.kernel.org/r/20200720082709.252805-1-pihsun@chromium.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is a regression introduced by the "migrate from ll_rw_block usage
to BIO" patch.

Squashfs packs structures on byte boundaries, and due to that the length
field (of the metadata block) may not be fully in the current block.
The new code rewrote and introduced a faulty check for that edge case.

Fixes: 93e72b3c ("squashfs: migrate from ll_rw_block usage to BIO")
Reported-by: Bernd Amend <bernd.amend@gmail.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Adrien Schildknecht <adrien+dev@schischi.me>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Daniel Rosenberg <drosen@google.com>
Link: http://lkml.kernel.org/r/20200717195536.16069-1-phillip@squashfs.org.ukSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add an entry to correct my email addresses.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200708095414.12275-1-rppt@kernel.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

khugepaged has to drop mmap lock several times while collapsing a page.
The situation can change while the lock is dropped and we need to
re-validate that the VMA is still in place and the PMD is still subject
for collapse.

But we miss one corner case: while collapsing an anonymous pages the VMA
could be replaced with file VMA.  If the file VMA doesn't have any
private pages we get NULL pointer dereference:

	general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
	KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
	anon_vma_lock_write include/linux/rmap.h:120 [inline]
	collapse_huge_page mm/khugepaged.c:1110 [inline]
	khugepaged_scan_pmd mm/khugepaged.c:1349 [inline]
	khugepaged_scan_mm_slot mm/khugepaged.c:2110 [inline]
	khugepaged_do_scan mm/khugepaged.c:2193 [inline]
	khugepaged+0x3bba/0x5a10 mm/khugepaged.c:2238

The fix is to make sure that the VMA is anonymous in
hugepage_vma_revalidate().  The helper is only used for collapsing
anonymous pages.

Fixes: 99cb0dbd ("mm,thp: add read-only THP support for (non-shmem) FS")
Reported-by: syzbot+ed318e8b790ca72c5ad0@syzkaller.appspotmail.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200722121439.44328-1-kirill.shutemov@linux.intel.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hugetlb_cma[0] can be NULL due to various reasons, for example, node0
has no memory.  so NULL hugetlb_cma[0] doesn't necessarily mean cma is
not enabled.  gigantic pages might have been reserved on other nodes.
This patch fixes possible double reservation and CMA leak.

[akpm@linux-foundation.org: fix CONFIG_CMA=n warning]
[sfr@canb.auug.org.au: better checks before using hugetlb_cma]
  Link: http://lkml.kernel.org/r/20200721205716.6dbaa56b@canb.auug.org.au

Fixes: cf11e85f ("mm: hugetlb: optionally allocate gigantic hugepages using cma")
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200710005726.36068-1-song.bao.hua@hisilicon.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If the kmem_cache refcount is greater than one, we should not mark the
root kmem_cache as dying.  If we mark the root kmem_cache dying
incorrectly, the non-root kmem_cache can never be destroyed.  It
resulted in memory leak when memcg was destroyed.  We can use the
following steps to reproduce.

  1) Use kmem_cache_create() to create a new kmem_cache named A.
  2) Coincidentally, the kmem_cache A is an alias for kmem_cache B,
     so the refcount of B is just increased.
  3) Use kmem_cache_destroy() to destroy the kmem_cache A, just
     decrease the B's refcount but mark the B as dying.
  4) Create a new memory cgroup and alloc memory from the kmem_cache
     B. It leads to create a non-root kmem_cache for allocating memory.
  5) When destroy the memory cgroup created in the step 4), the
     non-root kmem_cache can never be destroyed.

If we repeat steps 4) and 5), this will cause a lot of memory leak.  So
only when refcount reach zero, we mark the root kmem_cache as dying.

Fixes: 92ee383f ("mm: fix race between kmem_cache destroy, create and deactivate")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200716165103.83462-1-songmuchun@bytedance.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

It was hard to keep a test running, moving tasks between memcgs with
move_charge_at_immigrate, while swapping: mem_cgroup_id_get_many()'s
refcount is discovered to be 0 (supposedly impossible), so it is then
forced to REFCOUNT_SATURATED, and after thousands of warnings in quick
succession, the test is at last put out of misery by being OOM killed.

This is because of the way moved_swap accounting was saved up until the
task move gets completed in __mem_cgroup_clear_mc(), deferred from when
mem_cgroup_move_swap_account() actually exchanged old and new ids.
Concurrent activity can free up swap quicker than the task is scanned,
bringing id refcount down 0 (which should only be possible when
offlining).

Just skip that optimization: do that part of the accounting immediately.

Fixes: 615d66c3 ("mm: memcontrol: fix memcg id ref counter on swap charge move")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2007071431050.4726@eggly.anvilsSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Prabhakar reported an OOPS inside mem_cgroup_get_nr_swap_pages()
function in a corner case seen on some arm64 boards when kdump kernel
runs with "cgroup_disable=memory" passed to the kdump kernel via
bootargs.

The root-cause behind the same is that currently mem_cgroup_swap_init()
function is implemented as a subsys_initcall() call instead of a
core_initcall(), this means 'cgroup_memory_noswap' still remains set to
the default value (false) even when memcg is disabled via
"cgroup_disable=memory" boot parameter.

This may result in premature OOPS inside mem_cgroup_get_nr_swap_pages()
function in corner cases:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000188
  Mem abort info:
    ESR = 0x96000006
    EC = 0x25: DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
  Data abort info:
    ISV = 0, ISS = 0x00000006
    CM = 0, WnR = 0
  [0000000000000188] user address but active_mm is swapper
  Internal error: Oops: 96000006 [#1] SMP
  Modules linked in:
  <..snip..>
  Call trace:
    mem_cgroup_get_nr_swap_pages+0x9c/0xf4
    shrink_lruvec+0x404/0x4f8
    shrink_node+0x1a8/0x688
    do_try_to_free_pages+0xe8/0x448
    try_to_free_pages+0x110/0x230
    __alloc_pages_slowpath.constprop.106+0x2b8/0xb48
    __alloc_pages_nodemask+0x2ac/0x2f8
    alloc_page_interleave+0x20/0x90
    alloc_pages_current+0xdc/0xf8
    atomic_pool_expand+0x60/0x210
    __dma_atomic_pool_init+0x50/0xa4
    dma_atomic_pool_init+0xac/0x158
    do_one_initcall+0x50/0x218
    kernel_init_freeable+0x22c/0x2d0
    kernel_init+0x18/0x110
    ret_from_fork+0x10/0x18
  Code: aa1403e3 91106000 97f82a27 14000011 (f940c663)
  ---[ end trace 9795948475817de4 ]---
  Kernel panic - not syncing: Fatal exception
  Rebooting in 10 seconds..

Fixes: eccb52e7 ("mm: memcontrol: prepare swap controller setup for integration")
Reported-by: Prabhakar Kushwaha <pkushwaha@marvell.com>
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: http://lkml.kernel.org/r/1593641660-13254-2-git-send-email-bhsharma@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clang static analysis reports a garbage return

  In file included from mm/memory.c:84:
  mm/memory.c:1612:2: warning: Undefined or garbage value returned to caller [core.uninitialized.UndefReturn]
          return err;
          ^~~~~~~~~~

The setting of err depends on a loop executing.  So initialize err.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200703155354.29132-1-trix@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After commit fdc85222 ("kernfs: kvmalloc xattr value instead of
kmalloc"), simple xattr entry is allocated with kvmalloc() instead of
kmalloc(), so we should release it with kvfree() instead of kfree().

Fixes: fdc85222 ("kernfs: kvmalloc xattr value instead of kmalloc")
Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Daniel Xu <dxu@dxuuu.xyz>
Cc: Chris Down <chris@chrisdown.name>
Cc: Andreas Dilger <adilger@dilger.ca>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>	[5.7]
Link: http://lkml.kernel.org/r/20200704051608.15043-1-cgxu519@mykernel.netSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

VMA with VM_GROWSDOWN or VM_GROWSUP flag set can change their size under
mmap_read_lock().  It can lead to race with __do_munmap():

	Thread A			Thread B
__do_munmap()
  detach_vmas_to_be_unmapped()
  mmap_write_downgrade()
				expand_downwards()
				  vma->vm_start = address;
				  // The VMA now overlaps with
				  // VMAs detached by the Thread A
				// page fault populates expanded part
				// of the VMA
  unmap_region()
    // Zaps pagetables partly
    // populated by Thread B

Similar race exists for expand_upwards().

The fix is to avoid downgrading mmap_lock in __do_munmap() if detached
VMAs are next to VM_GROWSDOWN or VM_GROWSUP VMA.

[akpm@linux-foundation.org: s/mmap_sem/mmap_lock/ in comment]

Fixes: dd2283f2 ("mm: mmap: zap pages with read mmap_sem in munmap")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>	[4.20+]
Link: http://lkml.kernel.org/r/20200709105309.42495-1-kirill.shutemov@linux.intel.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull s390 fixes from Heiko Carstens:

 - Change cpum_cf/perf counter name from DFLT_CCERROR to DFLT_CCFINISH
   to reflect reality and avoid further confusion. This is a user space
   visible change therefore the commit has also a stable tag for 5.7,
   where this counter was introduced.

 - Add Matthew Rosato as s390 IOMMU maintainer.

* tag 's390-5.8-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  MAINTAINERS: add Matthew for s390 IOMMU
  s390/cpum_cf,perf: change DFLT_CCERROR counter name

When I have KASAN enabled on my kernel and I start stressing the
touchscreen my system tends to hang.  The touchscreen is one of the
only things that does a lot of big i2c transfers and ends up hitting
the DMA paths in the geni i2c driver.  It appears that KASAN adds
enough delay in my system to tickle a race condition in the DMA setup
code.

When the system hangs, I found that it was running the geni_i2c_irq()
over and over again.  It had these:

m_stat   = 0x04000080
rx_st    = 0x30000011
dm_tx_st = 0x00000000
dm_rx_st = 0x00000000
dma      = 0x00000001

Notably we're in DMA mode but are getting M_RX_IRQ_EN and
M_RX_FIFO_WATERMARK_EN over and over again.

Putting some traces in geni_i2c_rx_one_msg() showed that when we
failed we were getting to the start of geni_i2c_rx_one_msg() but were
never executing geni_se_rx_dma_prep().

I believe that the problem here is that we are starting the geni
command before we run geni_se_rx_dma_prep().  If a transfer makes it
far enough before we do that then we get into the state I have
observed.  Let's change the order, which seems to work fine.

Although problems were seen on the RX path, code inspection suggests
that the TX should be changed too.  Change it as well.

Fixes: 37692de5 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Akash Asthana <akashast@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Mukesh Kumar Savaliya <msavaliy@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

On R-Car Gen2, we get a timeout when reading from the address set in
ICSAR, even though the slave interface is disabled. Clearing it fixes
this situation. Note that Gen3 is not affected.

To reproduce: bind and undbind an I2C slave on some bus, run
'i2cdetect' on that bus.

Fixes: de20d185 ("i2c: rcar: add slave support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Commit adc0daad ("dm: report suspended
device during destroy") broke integrity recalculation.

The problem is dm_suspended() returns true not only during suspend,
but also during resume. So this race condition could occur:
1. dm_integrity_resume calls queue_work(ic->recalc_wq, &ic->recalc_work)
2. integrity_recalc (&ic->recalc_work) preempts the current thread
3. integrity_recalc calls if (unlikely(dm_suspended(ic->ti))) goto unlock_ret;
4. integrity_recalc exits and no recalculating is done.

To fix this race condition, add a function dm_post_suspending that is
only true during the postsuspend phase and use it instead of
dm_suspended().

Signed-off-by: Mikulas Patocka <mpatocka redhat com>
Fixes: adc0daad ("dm: report suspended device during destroy")
Cc: stable vger kernel org # v4.18+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

IOSQE_ASYNC branch of io_queue_sqe() is another place where an
unitialised req->work can be accessed (i.e. prior io_req_init_async()).
Nothing really bad though, it just looses IO_WQ_WORK_CONCURRENT flag.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Newer versions of clang only look for $(COMPAT_GCC_TOOLCHAIN_DIR)as [1],
rather than $(COMPAT_GCC_TOOLCHAIN_DIR)$(CROSS_COMPILE_COMPAT)as,
resulting in the following build error:

$ make -skj"$(nproc)" ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
CROSS_COMPILE_COMPAT=arm-linux-gnueabi- LLVM=1 O=out/aarch64 distclean \
defconfig arch/arm64/kernel/vdso32/
...
/home/nathan/cbl/toolchains/llvm-binutils/bin/as: unrecognized option '-EL'
clang-12: error: assembler command failed with exit code 1 (use -v to see invocation)
make[3]: *** [arch/arm64/kernel/vdso32/Makefile:181: arch/arm64/kernel/vdso32/note.o] Error 1
...

Adding the value of CROSS_COMPILE_COMPAT (adding notdir to account for a
full path for CROSS_COMPILE_COMPAT) fixes this issue, which matches the
solution done for the main Makefile [2].

[1]: https://github.com/llvm/llvm-project/commit/3452a0d8c17f7166f479706b293caf6ac76ffd90
[2]: https://lore.kernel.org/lkml/20200721173125.1273884-1-maskray@google.com/Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1099
Link: https://lore.kernel.org/r/20200723041509.400450-1-natechancellor@gmail.comSigned-off-by: Will Deacon <will@kernel.org>

Merge tag 'amd-drm-fixes-5.8-2020-07-22' of git://people.freedesktop.org/~agd5f/linux into drm-fixes

amd-drm-fixes-5.8-2020-07-22:

amdgpu:
- Fix crash when overclocking VegaM
- Fix possible crash when editing dpm levels
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200723032608.3865-1-alexander.deucher@amd.com

 * sun4i: Fix inverted HPD result; fixes an earlier fix
 * lima: fix timeout during reset
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200722070321.GA29190@linux-uq9g

We hold the cl_lock here, and that's enough to keep stateid's from going
away, but it's not enough to prevent the files they point to from going
away.  Take fi_lock and a reference and check for NULL, as we do in
other code.
Reported-by: NeilBrown <neilb@suse.de>
Fixes: 78599c42 ("nfsd4: add file to display list of client's opens")
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Merge tag 'media/v5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media into master

Pull media fixes from Mauro Carvalho Chehab:
 "A series of fixes for the upcoming atomisp driver. They solve issues
  when probing atomisp on devices with multiple cameras and get rid of
  warnings when built with W=1.

  The diffstat is a bit long, as this driver has several abstractions.
  The patches that solved the issues with W=1 had to get rid of some
  duplicated code (there used to have 2 versions of the same code, one
  for ISP2401 and another one for ISP2400).

  As this driver is not in 5.7, such changes won't cause regressions"

* tag 'media/v5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (38 commits)
  Revert "media: atomisp: keep the ISP powered on when setting it"
  media: atomisp: fix mask and shift operation on ISPSSPM0
  media: atomisp: move system_local consts into a C file
  media: atomisp: get rid of version-specific system_local.h
  media: atomisp: move global stuff into a common header
  media: atomisp: remove non-used 32-bits consts at system_local
  media: atomisp: get rid of some unused static vars
  media: atomisp: Fix error code in ov5693_probe()
  media: atomisp: Replace trace_printk by pr_info
  media: atomisp: Fix __func__ style warnings
  media: atomisp: fix help message for ISP2401 selection
  media: atomisp: i2c: atomisp-ov2680.c: fixed a brace coding style issue.
  media: atomisp: make const arrays static, makes object smaller
  media: atomisp: Clean up non-existing folders from Makefile
  media: atomisp: Get rid of ACPI specifics in gmin_subdev_add()
  media: atomisp: Provide Gmin subdev as parameter to gmin_subdev_add()
  media: atomisp: Use temporary variable for device in gmin_subdev_add()
  media: atomisp: Refactor PMIC detection to a separate function
  media: atomisp: Deduplicate return ret in gmin_i2c_write()
  media: atomisp: Make pointer to PMIC client global
  ...

Merge tag 'exfat-for-5.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat into master

Pull exfat fixes from Namjae Jeon:

 - fix overflow issue at sector calculation

 - fix wrong hint_stat initialization

 - fix wrong size update of stream entry

 - fix endianness of upname in name_hash computation

* tag 'exfat-for-5.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: fix name_hash computation on big endian systems
  exfat: fix wrong size update of stream entry by typo
  exfat: fix wrong hint_stat initialization in exfat_find_dir_entry()
  exfat: fix overflow issue in exfat_cluster_to_sector()

The device may be torn down, but the domain should still be valid.  Lets
use that as the tlb flush ops cookie.

Fixes a problem reported in [1]

[1] https://lkml.org/lkml/2020/7/20/104Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 09b5dfff ("iommu/qcom: Use accessor functions for iommu private data")
Link: https://lore.kernel.org/r/20200720155217.274994-1-robdclark@gmail.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

Acked-By: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>