dm_queue_split() is removed because __split_and_process_bio() _must_
handle splitting bios to ensure proper bio submission and completion
ordering as a bio is split.

Otherwise, multiple recursive calls to ->submit_bio will cause multiple
split bios to be allocated from the same ->bio_split mempool at the same
time. This would result in deadlock in low memory conditions because no
progress could be made (only one bio is available in ->bio_split
mempool).

This fix has been verified to still fix the loss of performance, due
to excess splitting, that commit 120c9257 provided.

Fixes: 120c9257 ("Revert "dm: always call blk_queue_split() in dm_process_bio()"")
Cc: stable@vger.kernel.org # 5.0+, requires custom backport due to 5.9 changes
Reported-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

Pull kvm fixes from Paolo Bonzini:
 "ARM:
   - fix fault on page table writes during instruction fetch

  s390:
   - doc improvement

  x86:
   - The obvious patches are always the ones that turn out to be
     completely broken. /me hangs his head in shame"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  Revert "KVM: Check the allocation of pv cpu mask"
  KVM: arm64: Remove S1PTW check from kvm_vcpu_dabt_iswrite()
  KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetch
  docs: kvm: add documentation for KVM_CAP_S390_DIAG318

Pull libnvdimm fix from Dan Williams:
 "Fix compilation for the new dax_supported() exported helper"

* tag 'libnvdimm-fixes-5.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix compilation for CONFIG_DAX && !CONFIG_FS_DAX

dax_supported() is defined whenever CONFIG_DAX is enabled. So dummy
implementation should be defined only in !CONFIG_DAX case, not in
!CONFIG_FS_DAX case.

Fixes: e2ec5128 ("dm: Call proper helper to determine dax support")
Cc: <stable@vger.kernel.org>
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Reported-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Pull syscall tracing fix from Borislav Petkov:
 "Fix the seccomp syscall rewriting so that trace and audit see the
  rewritten syscall number, from Kees Cook"

* tag 'core_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  core/entry: Report syscall correctly for trace and audit

Pull objtool fix from Borislav Petkov:
 "Fix noreturn detection for ignored sibling functions (Josh Poimboeuf)"

* tag 'objtool_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix noreturn detection for ignored functions

Pull locking fixes from Borislav Petkov:
 "Two fixes from the locking/urgent pile:

   - Fix lockdep's detection of "USED" <- "IN-NMI" inversions (Peter
     Zijlstra)

   - Make percpu-rwsem operations on the semaphore's ->read_count
     IRQ-safe because it can be used in an IRQ context (Hou Tao)"

* tag 'locking_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/percpu-rwsem: Use this_cpu_{inc,dec}() for read_count
  locking/lockdep: Fix "USED" <- "IN-NMI" inversions

Pull EFI fix from Borislav Petkov:
 "Ensure that the EFI bootloader control module only probes successfully
  on systems that support the EFI SetVariable runtime service"

[ Tag and commit from Ard Biesheuvel, forwarded by Borislav ]

* tag 'efi-urgent-for-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: efibc: check for efivars write capability

Pull x86 fixes from Borislav Petkov:

 - A defconfig fix (Daniel Díaz)

 - Disable relocation relaxation for the compressed kernel when not
   built as -pie as in that case kernels built with clang and linked
   with LLD fail to boot due to the linker optimizing some instructions
   in non-PIE form; the gory details in the commit message (Arvind
   Sankar)

 - A fix for the "bad bp value" warning issued by the frame-pointer
   unwinder (Josh Poimboeuf)

* tag 'x86_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/fp: Fix FP unwinding in ret_from_fork
  x86/boot/compressed: Disable relocation relaxation
  x86/defconfigs: Explicitly unset CONFIG_64BIT in i386_defconfig

Pull libnvdimm fixes from Dan Williams:
 "A handful of fixes to address a string of mistakes in the mechanism
  for device-mapper to determine if its component devices are dax
  capable.

   - Fix an original bug in device-mapper table reference counting when
     interrogating dax capability in the component device. This bug was
     hidden by the following bug.

   - Fix device-mapper to use the proper helper (dax_supported() instead
     of the leaf helper generic_fsdax_supported()) to determine dax
     operation of a stacked block device configuration. The original
     implementation is only valid for one level of dax-capable block
     device stacking. This bug was discovered while fixing the below
     regression.

   - Fix an infinite recursion regression introduced by broken attempts
     to quiet the generic_fsdax_supported() path and make it bail out
     before logging "dax capability not found" errors"

* tag 'libnvdimm-fixes-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix stack overflow when mounting fsdax pmem device
  dm: Call proper helper to determine dax support
  dm/dax: Fix table reference counts

Merge tag 'kvm-s390-master-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-master

KVM: s390: add documentation for KVM_CAP_S390_DIAG318

diag318 code was merged in 5.9-rc1, let us add some
missing documentation

Merge tag 'kvmarm-fixes-5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

KVM/arm64 fixes for 5.9, take #2

- Fix handling of S1 Page Table Walk permission fault at S2
  on instruction fetch
- Cleanup kvm_vcpu_dabt_iswrite()

The commit 0f990222 ("KVM: Check the allocation of pv cpu mask") we
have in 5.9-rc5 has two issue:
1) Compilation fails for !CONFIG_SMP, see:
   https://bugzilla.kernel.org/show_bug.cgi?id=209285

2) This commit completely disables PV TLB flush, see
   https://lore.kernel.org/kvm/87y2lrnnyf.fsf@vitty.brq.redhat.com/

The allocation problem is likely a theoretical one, if we don't
have memory that early in boot process we're likely doomed anyway.
Let's solve it properly later.

This reverts commit 0f990222.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Pull RISC-V fixes from Palmer Dabbelt:

 - A fix for a lockdep issue to avoid an asserting triggering during
   early boot. There shouldn't be any incorrect behavior as the system
   isn't concurrent at the time.

 - The addition of a missing fence when installing early fixmap
   mappings.

 - A corretion to the K210 device tree's interrupt map.

 - A fix for M-mode timer handling on the K210.

* tag 'riscv-for-linus-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  RISC-V: Resurrect the MMIO timer implementation for M-mode systems
  riscv: Fix Kendryte K210 device tree
  riscv: Add sfence.vma after early page table changes
  RISC-V: Take text_mutex in ftrace_init_nop()

Pull USB/Thunderbolt fixes from Greg KH:
 "Here are some small USB and one Thunderbolt driver fixes.

  Nothing major at all, just some fixes for reported issues, and a quirk
  addition:

   - typec fixes

   - UAS disconnect fix

   - usblp race fix

   - ehci-hcd modversions build fix

   - ignore wakeup quirk table addition

   - thunderbolt DROM read fix

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

* tag 'usb-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usblp: fix race between disconnect() and read()
  ehci-hcd: Move include to keep CRC stable
  usb: typec: intel_pmc_mux: Handle SCU IPC error conditions
  USB: quirks: Add USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk for BYD zhaoxin notebook
  USB: UAS: fix disconnect by unplugging a hub
  usb: typec: ucsi: Prevent mode overrun
  usb: typec: ucsi: acpi: Increase command completion timeout value
  thunderbolt: Retry DROM read once if parsing fails

Pull tty/serial/fbcon fixes from Greg KH:
 "Here are some small tty/serial and one more fbcon fix.

  They include:

   - serial core locking regression fixes

   - new device ids for 8250_pci driver

   - fbcon fix for syzbot found issue

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

* tag 'tty-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  fbcon: Fix user font detection test at fbcon_resize().
  serial: 8250_pci: Add Realtek 816a and 816b
  serial: core: fix console port-lock regression
  serial: core: fix port-lock initialisation

Pull EDAC fixes from Borislav Petkov:
 "Two fixes for resulting from CONFIG_DEBUG_TEST_DRIVER_REMOVE=y
  experiments:

   - complete a previous fix to reset a local structure containing
     scanned system data properly so that the driver rescans, as it
     should, on a second load.

   - address a refcount underflow due to not paying attention to the
     driver whitelest on unregister"

* tag 'edac_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/ghes: Check whether the driver is on the safe list correctly
  EDAC/ghes: Clear scanned data on unload

Pull input fixes from Dmitry Torokhov:
 "Just a couple of driver quirks"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: trackpoint - add new trackpoint variant IDs
  Input: i8042 - add Entroware Proteus EL07R4 to nomux and reset lists

Sedat Dilek pointed out some silly comment typo issues.
Reported-by: NSedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge tag 'kbuild-fixes-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:
 "Fix qconf warnings and revive help message"

* tag 'kbuild-fixes-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: qconf: revive help message in the info view
  kconfig: qconf: fix incomplete type 'struct gstr' warning
  kconfig: qconf: use delete[] instead of delete to free array (again)

When mounting fsdax pmem device, commit 6180bb44 ("dax: fix
detection of dax support for non-persistent memory block devices")
introduces the stack overflow [1][2]. Here is the call path for
mounting ext4 file system:
  ext4_fill_super
    bdev_dax_supported
      __bdev_dax_supported
        dax_supported
          generic_fsdax_supported
            __generic_fsdax_supported
              bdev_dax_supported

The call path leads to the infinite calling loop, so we cannot
call bdev_dax_supported() in __generic_fsdax_supported(). The sanity
checking of the variable 'dax_dev' is moved prior to the two
bdev_dax_pgoff() checks [3][4].

[1] https://lore.kernel.org/linux-nvdimm/1420999447.1004543.1600055488770.JavaMail.zimbra@redhat.com/
[2] https://lore.kernel.org/linux-nvdimm/alpine.LRH.2.02.2009141131220.30651@file01.intranet.prod.int.rdu2.redhat.com/
[3] https://lore.kernel.org/linux-nvdimm/CA+RJvhxBHriCuJhm-D8NvJRe3h2MLM+ZMFgjeJjrRPerMRLvdg@mail.gmail.com/
[4] https://lore.kernel.org/linux-nvdimm/20200903160608.GU878166@iweiny-DESK2.sc.intel.com/

Fixes: 6180bb44 ("dax: fix detection of dax support for non-persistent memory block devices")
Reported-by: NYi Zhang <yi.zhang@redhat.com>
Reported-by: NMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NAdrian Huang <ahuang12@lenovo.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Tested-by: NRitesh Harjani <riteshh@linux.ibm.com>
Cc: Coly Li <colyli@suse.de>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: John Pittman <jpittman@redhat.com>
Link: https://lore.kernel.org/r/20200917111549.6367-1-adrianhuang0701@gmail.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

DM was calling generic_fsdax_supported() to determine whether a device
referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that
they don't have to duplicate common generic checks. High level code
should call dax_supported() helper which that calls into appropriate
helper for the particular device. This problem manifested itself as
kernel messages:

dm-3: error: dax access failed (-95)

when lvm2-testsuite run in cases where a DM device was stacked on top of
another DM device.

Fixes: 7bf7eac8 ("dax: Arrange for dax_supported check to span multiple devices")
Cc: <stable@vger.kernel.org>
Tested-by: NAdrian Huang <ahuang12@lenovo.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Acked-by: NMike Snitzer <snitzer@redhat.com>
Reported-by: Nkernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

A recent fix to the dm_dax_supported() flow uncovered a latent bug. When
dm_get_live_table() fails it is still required to drop the
srcu_read_lock(). Without this change the lvm2 test-suite triggers this
warning:

    # lvm2-testsuite --only pvmove-abort-all.sh

    WARNING: lock held when returning to user space!
    5.9.0-rc5+ #251 Tainted: G           OE
    ------------------------------------------------
    lvm/1318 is leaving the kernel with locks still held!
    1 lock held by lvm/1318:
     #0: ffff9372abb5a340 (&md->io_barrier){....}-{0:0}, at: dm_get_live_table+0x5/0xb0 [dm_mod]

...and later on this hang signature:

    INFO: task lvm:1344 blocked for more than 122 seconds.
          Tainted: G           OE     5.9.0-rc5+ #251
    "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
    task:lvm             state:D stack:    0 pid: 1344 ppid:     1 flags:0x00004000
    Call Trace:
     __schedule+0x45f/0xa80
     ? finish_task_switch+0x249/0x2c0
     ? wait_for_completion+0x86/0x110
     schedule+0x5f/0xd0
     schedule_timeout+0x212/0x2a0
     ? __schedule+0x467/0xa80
     ? wait_for_completion+0x86/0x110
     wait_for_completion+0xb0/0x110
     __synchronize_srcu+0xd1/0x160
     ? __bpf_trace_rcu_utilization+0x10/0x10
     __dm_suspend+0x6d/0x210 [dm_mod]
     dm_suspend+0xf6/0x140 [dm_mod]

Fixes: 7bf7eac8 ("dax: Arrange for dax_supported check to span multiple devices")
Cc: <stable@vger.kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Reported-by: NAdrian Huang <ahuang12@lenovo.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Tested-by: NAdrian Huang <ahuang12@lenovo.com>
Link: https://lore.kernel.org/r/160045867590.25663.7548541079217827340.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Since commit 68fd110b ("kconfig: qconf: remove redundant help in
the info view"), the help message is no longer displayed.

I intended to drop duplicated "Symbol:", "Type:", but precious info
about help and reverse dependencies was lost too.

Revive it now.

"defined at" is contained in menu_get_ext_help(), so I made sure
to not display it twice.

Fixes: 68fd110b ("kconfig: qconf: remove redundant help in the info view")
Reported-by: NMaxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

"make HOSTCXX=clang++ xconfig" reports the following:

  HOSTCXX scripts/kconfig/qconf.o
In file included from scripts/kconfig/qconf.cc:23:
In file included from scripts/kconfig/lkc.h:15:
scripts/kconfig/lkc_proto.h:26:13: warning: 'get_relations_str' has C-linkage specified, but returns incomplete type 'struct gstr' which could be incompatible with C [-Wreturn-type-c-linkage]
struct gstr get_relations_str(struct symbol **sym_arr, struct list_head *head);
            ^

Currently, get_relations_str() is declared before the struct gstr
definition.

Move all declarations of menu.c functions below.

BTW, some are declared in lkc.h and some in lkc_proto.h, but the
difference is unclear. I guess some refactoring is needed.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Acked-by: NBoris Kolpackov <boris@codesynthesis.com>

Merge fixes from Andrew Morton:
 "15 patches.

  Subsystems affected by this patch series: mailmap, mm/hotfixes,
  mm/thp, mm/memory-hotplug, misc, kcsan"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments'
  fs/fs-writeback.c: adjust dirtytime_interval_handler definition to match prototype
  stackleak: let stack_erasing_sysctl take a kernel pointer buffer
  ftrace: let ftrace_enable_sysctl take a kernel pointer buffer
  mm/memory_hotplug: drain per-cpu pages again during memory offline
  selftests/vm: fix display of page size in map_hugetlb
  mm/thp: fix __split_huge_pmd_locked() for migration PMD
  kprobes: fix kill kprobe which has been marked as gone
  tmpfs: restore functionality of nr_inodes=0
  mlock: fix unevictable_pgs event counts on THP
  mm: fix check_move_unevictable_pages() on THP
  mm: migration of hugetlbfs page skip memcg
  ksm: reinstate memcg charge on copied pages
  mailmap: add older email addresses for Kees Cook

Pull i2c fixes from Wolfram Sang:
 "Another bunch of fixes for I2C.

  Jean's i801 patch is a cleanup on top of Volker's i801 patch, but it
  will make dependency handling much easier if those two go together"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: mxs: use MXS_DMA_CTRL_WAIT4END instead of DMA_CTRL_ACK
  i2c: mediatek: Send i2c master code at more than 1MHz
  i2c: mediatek: Fix generic definitions for bus frequency
  i2c: core: Call i2c_acpi_install_space_handler() before i2c_acpi_register_devices()
  i2c: i801: Simplify the suspend callback
  i2c: i801: Fix resume bug
  i2c: aspeed: Mask IRQ status to relevant bits

The K210 doesn't implement rdtime in M-mode, and since that's where Linux runs
in the NOMMU systems that means we can't use rdtime.  The K210 is the only
system that anyone is currently running NOMMU or M-mode on, so here we're just
inlining the timer read directly.

This also adds the CLINT driver as an !MMU dependency, as it's currently the
only timer driver availiable for these systems and without it we get a build
failure for some configurations.
Tested-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>

The Kendryte K210 SoC CLINT is compatible with Sifive clint v0
(sifive,clint0). Fix the Kendryte K210 device tree clint entry to be
inline with the sifive timer definition documented in
Documentation/devicetree/bindings/timer/sifive,clint.yaml.
The device tree clint entry is renamed similarly to u-boot device tree
definition to improve compatibility with u-boot defined device tree.
To ensure correct initialization, the interrup-cells attribute is added
and the interrupt-extended attribute definition fixed.

This fixes boot failures with Kendryte K210 SoC boards.

Note that the clock referenced is kept as K210_CLK_ACLK, which does not
necessarilly match the clint MTIME increment rate. This however does not
seem to cause any problem for now.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>

This invalidates local TLB after modifying the page tables during early init as
it's too early to handle suprious faults as we otherwise do.

Fixes: f2c17aab ("RISC-V: Implement compile-time fixed mappings")
Reported-by: NSyven Wang <syven.wang@sifive.com>
Signed-off-by: NSyven Wang <syven.wang@sifive.com>
Signed-off-by: NGreentime Hu <greentime.hu@sifive.com>
Reviewed-by: NAnup Patel <anup@brainfault.org>
[Palmer: Cleaned up the commit text]
Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>

This moves the KCSAN kconfig items under menu 'Generic Kernel Debugging
Instruments' where UBSAN resides.
Signed-off-by: NChangbin Du <changbin.du@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NRandy Dunlap <rdunlap@infradead.org>
Reviewed-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200904152224.5570-1-changbin.du@gmail.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer.  Adjust the
definition of dirtytime_interval_handler to match its prototype in
linux/writeback.h which fixes the following sparse error/warning:

fs/fs-writeback.c:2189:50: warning: incorrect type in argument 3 (different address spaces)
fs/fs-writeback.c:2189:50:    expected void *
fs/fs-writeback.c:2189:50:    got void [noderef] __user *buffer
fs/fs-writeback.c:2184:5: error: symbol 'dirtytime_interval_handler' redeclared with different type (incompatible argument 3 (different address spaces)):
fs/fs-writeback.c:2184:5:    int extern [addressable] [signed] [toplevel] dirtytime_interval_handler( ... )
fs/fs-writeback.c: note: in included file:
./include/linux/writeback.h:374:5: note: previously declared as:
./include/linux/writeback.h:374:5:    int extern [addressable] [signed] [toplevel] dirtytime_interval_handler( ... )

Fixes: 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/20200907093140.13434-1-tklauser@distanz.chSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer.  Adjust the
signature of stack_erasing_sysctl to match ctl_table.proc_handler which
fixes the following sparse warning:

kernel/stackleak.c:31:50: warning: incorrect type in argument 3 (different address spaces)
kernel/stackleak.c:31:50:    expected void *
kernel/stackleak.c:31:50:    got void [noderef] __user *buffer

Fixes: 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/20200907093253.13656-1-tklauser@distanz.chSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer.  Adjust the
signature of ftrace_enable_sysctl to match ctl_table.proc_handler which
fixes the following sparse warning:

kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces)
kernel/trace/ftrace.c:7544:43:    expected void *
kernel/trace/ftrace.c:7544:43:    got void [noderef] __user *buffer

Fixes: 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/20200907093207.13540-1-tklauser@distanz.chSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is a race during page offline that can lead to infinite loop:
a page never ends up on a buddy list and __offline_pages() keeps
retrying infinitely or until a termination signal is received.

Thread#1 - a new process:

load_elf_binary
 begin_new_exec
  exec_mmap
   mmput
    exit_mmap
     tlb_finish_mmu
      tlb_flush_mmu
       release_pages
        free_unref_page_list
         free_unref_page_prepare
          set_pcppage_migratetype(page, migratetype);
             // Set page->index migration type below  MIGRATE_PCPTYPES

Thread#2 - hot-removes memory
__offline_pages
  start_isolate_page_range
    set_migratetype_isolate
      set_pageblock_migratetype(page, MIGRATE_ISOLATE);
        Set migration type to MIGRATE_ISOLATE-> set
        drain_all_pages(zone);
             // drain per-cpu page lists to buddy allocator.

Thread#1 - continue
         free_unref_page_commit
           migratetype = get_pcppage_migratetype(page);
              // get old migration type
           list_add(&page->lru, &pcp->lists[migratetype]);
              // add new page to already drained pcp list

Thread#2
Never drains pcp again, and therefore gets stuck in the loop.

The fix is to try to drain per-cpu lists again after
check_pages_isolated_cb() fails.

Fixes: c52e7593 ("mm: remove extra drain pages on pcp list")
Signed-off-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NDavid Rientjes <rientjes@google.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200903140032.380431-1-pasha.tatashin@soleen.com
Link: https://lkml.kernel.org/r/20200904151448.100489-2-pasha.tatashin@soleen.com
Link: http://lkml.kernel.org/r/20200904070235.GA15277@dhcp22.suse.czSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The displayed size is in bytes while the text says it is in kB.

Shift it by 10 to really display kBytes.

Fixes: fa7b9a80 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb")
Signed-off-by: NChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/e27481224564a93d14106e750de31189deaa8bc8.1598861977.git.christophe.leroy@csgroup.euSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A migrating transparent huge page has to already be unmapped.  Otherwise,
the page could be modified while it is being copied to a new page and data
could be lost.  The function __split_huge_pmd() checks for a PMD migration
entry before calling __split_huge_pmd_locked() leading one to think that
__split_huge_pmd_locked() can handle splitting a migrating PMD.

However, the code always increments the page->_mapcount and adjusts the
memory control group accounting assuming the page is mapped.

Also, if the PMD entry is a migration PMD entry, the call to
is_huge_zero_pmd(*pmd) is incorrect because it calls pmd_pfn(pmd) instead
of migration_entry_to_pfn(pmd_to_swp_entry(pmd)).  Fix these problems by
checking for a PMD migration entry.

Fixes: 84c3fc4e ("mm: thp: check pmd migration entry in common path")
Signed-off-by: NRalph Campbell <rcampbell@nvidia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NYang Shi <shy828301@gmail.com>
Reviewed-by: NZi Yan <ziy@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>	[4.14+]
Link: https://lkml.kernel.org/r/20200903183140.19055-1-rcampbell@nvidia.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a kprobe is marked as gone, we should not kill it again.  Otherwise, we
can disarm the kprobe more than once.  In that case, the statistics of
kprobe_ftrace_enabled can unbalance which can lead to that kprobe do not
work.

Fixes: e8386a0c ("kprobes: support probing module __exit function")
Co-developed-by: NChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: NMuchun Song <songmuchun@bytedance.com>
Signed-off-by: NChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Song Liu <songliubraving@fb.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200822030055.32383-1-songmuchun@bytedance.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit e809d5f0 ("tmpfs: per-superblock i_ino support") made changes
to shmem_reserve_inode() in mm/shmem.c, however the original test for
(sbinfo->max_inodes) got dropped.  This causes mounting tmpfs with option
nr_inodes=0 to fail:

  # mount -ttmpfs -onr_inodes=0 none /ext0
  mount: /ext0: mount(2) system call failed: Cannot allocate memory.

This patch restores the nr_inodes=0 functionality.

Fixes: e809d5f0 ("tmpfs: per-superblock i_ino support")
Signed-off-by: NByron Stanoszek <gandalf@winds.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NHugh Dickins <hughd@google.com>
Acked-by: NChris Down <chris@chrisdown.name>
Link: https://lkml.kernel.org/r/20200902035715.16414-1-gandalf@winds.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>