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: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi 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.com


Signed-off-by: Linus 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: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Masami 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.com


Signed-off-by: Linus 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: Byron Stanoszek <gandalf@winds.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Chris Down <chris@chrisdown.name>
Link: https://lkml.kernel.org/r/20200902035715.16414-1-gandalf@winds.org


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5.8 commit 5d91f31f ("mm: swap: fix vmstats for huge page") has
established that vm_events should count every subpage of a THP, including
unevictable_pgs_culled and unevictable_pgs_rescued; but
lru_cache_add_inactive_or_unevictable() was not doing so for
unevictable_pgs_mlocked, and mm/mlock.c was not doing so for
unevictable_pgs mlocked, munlocked, cleared and stranded.

Fix them; but THPs don't go the pagevec way in mlock.c, so no fixes needed
on that path.

Fixes: 5d91f31f

 ("mm: swap: fix vmstats for huge page")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301408230.5954@eggly.anvils


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

check_move_unevictable_pages() is used in making unevictable shmem pages
evictable: by shmem_unlock_mapping(), drm_gem_check_release_pagevec() and
i915/gem check_release_pagevec().  Those may pass down subpages of a huge
page, when /sys/kernel/mm/transparent_hugepage/shmem_enabled is "force".

That does not crash or warn at present, but the accounting of vmstats
unevictable_pgs_scanned and unevictable_pgs_rescued is inconsistent:
scanned being incremented on each subpage, rescued only on the head (since
tails already appear evictable once the head has been updated).

5.8 commit 5d91f31f

 ("mm: swap: fix vmstats for huge page") has
established that vm_events in general (and unevictable_pgs_rescued in
particular) should count every subpage: so follow that precedent here.

Do this in such a way that if mem_cgroup_page_lruvec() is made stricter
(to check page->mem_cgroup is always set), no problem: skip the tails
before calling it, and add thp_nr_pages() to vmstats on the head.

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301405000.5954@eggly.anvils


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hugetlbfs pages do not participate in memcg: so although they do find most
of migrate_page_states() useful, it would be better if they did not call
into mem_cgroup_migrate() - where Qian Cai reported that LTP's
move_pages12 triggers the warning in Alex Shi's prospective commit
"mm/memcg: warning on !memcg after readahead page charged".

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxch.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301359460.5954@eggly.anvils


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "mm: fixes to past from future testing".

Here's a set of independent fixes against 5.9-rc2: prompted by
testing Alex Shi's "warning on !memcg" and lru_lock series, but
I think fit for 5.9 - though maybe only the first for stable.

This patch (of 5):

In 5.8 some instances of memcg charging in do_swap_page() and unuse_pte()
were removed, on the understanding that swap cache is now already charged
at those points; but a case was missed, when ksm_might_need_to_copy() has
decided it must allocate a substitute page: such pages were never charged.
Fix it inside ksm_might_need_to_copy().

This was discovered by Alex Shi's prospective commit "mm/memcg: warning on
!memcg after readahead page charged".

But there is a another surprise: this also fixes some rarer uncharged
PageAnon cases, when KSM is configured in, but has never been activated.
ksm_might_need_to_copy()'s anon_vma->root and linear_page_index() check
sometimes catches a case which would need to have been copied if KSM were
turned on.  Or that's my optimistic interpretation (of my own old code),
but it leaves some doubt as to whether everything is working as intended
there - might it hint at rare anon ptes which rmap cannot find?  A
question not easily answered: put in the fix for missed memcg charges.

Cc; Matthew Wilcox <willy@infradead.org>

Fixes: 4c6355b2

 ("mm: memcontrol: charge swapin pages on instantiation")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Cc: <stable@vger.kernel.org>	[5.8]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301343270.5954@eggly.anvils
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301358020.5954@eggly.anvils


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds explicit mailmap entries for my older/other email addresses.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lkml.kernel.org/r/20200910193939.3798377-1-keescook@chromium.org


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull arch/sh fixes from Rich Felker:
 "Fixes for build and function regression"

* tag 'sh-for-5.9-part2' of git://git.libc.org/linux-sh:
  sh: fix syscall tracing
  sh: remove spurious circular inclusion from asm/smp.h

Pull arm64 fixes from Catalin Marinas:

 - Allow CPUs affected by erratum 1418040 to come online late
   (previously we only fixed the other case - CPUs not affected by the
   erratum coming up late).

 - Fix branch offset in BPF JIT.

 - Defer the stolen time initialisation to the CPU online time from the
   CPU starting time to avoid a (sleep-able) memory allocation in an
   atomic context.

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: paravirt: Initialize steal time when cpu is online
  arm64: bpf: Fix branch offset in JIT
  arm64: Allow CPUs unffected by ARM erratum 1418040 to come in late

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.9:

   - Opt us out of the DEBUG_VM_PGTABLE support for now as it's causing
     crashes.

   - Fix a long standing bug in our DMA mask handling that was hidden
     until recently, and which caused problems with some drivers.

   - Fix a boot failure on systems with large amounts of RAM, and no
     hugepage support and using Radix MMU, only seen in the lab.

   - A few other minor fixes.

  Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Gautham R. Shenoy,
  Hari Bathini, Ira Weiny, Nick Desaulniers, Shirisha Ganta, Vaibhav
  Jain, and Vaidyanathan Srinivasan"

* tag 'powerpc-5.9-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Limit the readability of 'perf_stats' sysfs attribute
  cpuidle: pseries: Fix CEDE latency conversion from tb to us
  powerpc/dma: Fix dma_map_ops::get_required_mask
  Revert "powerpc/build: vdso linker warning for orphan sections"
  powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc
  selftests/powerpc: Skip PROT_SAO test in guests/LPARS
  powerpc/book3s64/radix: Fix boot failure with large amount of guest memory

Pull power management updates from Rafael Wysocki:
 "These add a new CPU ID to the RAPL power capping driver and prevent
  the ACPI processor idle driver from triggering RCU-lockdep complaints.

  Specifics:

   - Add support for the Lakefield chip to the RAPL power capping driver
     (Ricardo Neri).

   - Modify the ACPI processor idle driver to prevent it from triggering
     RCU-lockdep complaints which has started to happen after recent
     changes in that area (Peter Zijlstra)"

* tag 'pm-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: processor: Take over RCU-idle for C3-BM idle
  cpuidle: Allow cpuidle drivers to take over RCU-idle
  ACPI: processor: Use CPUIDLE_FLAG_TLB_FLUSHED
  ACPI: processor: Use CPUIDLE_FLAG_TIMER_STOP
  powercap: RAPL: Add support for Lakefield

Pull sound fixes from Takashi Iwai:
 "Here is a collection of fixes for 5.9. All look small and are nothing
  scary.

  The majority of changes are about ASoC driver- specific fixes, while
  there are a couple of ASoC core fixes (DAI lookup and lockdep stuff)
  and usual HD-audio quirks"

* tag 'sound-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (23 commits)
  ALSA: hda/realtek - The Mic on a RedmiBook doesn't work
  ASoC: tlv320adcx140: Wake up codec before accessing register
  ASoC: core: Do not cleanup uninitialized dais on soc_pcm_open failure
  ALSA: hda: fixup headset for ASUS GX502 laptop
  ASoC: Intel: bytcr_rt5640: Add quirk for MPMAN Converter9 2-in-1
  ASoC: Intel: haswell: Fix power transition refactor
  ASoC: tlv320adcx140: Fix accessing uninitialized adcx140->dev
  ASoC: wm8994: Ensure the device is resumed in wm89xx_mic_detect functions
  ASoC: wm8994: Skip setting of the WM8994_MICBIAS register for WM1811
  ASoC: meson: axg-toddr: fix channel order on g12 platforms
  ASoC: soc-core: add snd_soc_find_dai_with_mutex()
  ASoC: qcom: common: Fix refcount imbalance on error
  ASoC: rt700: Fix return check for devm_regmap_init_sdw()
  ASoC: rt715: Fix return check for devm_regmap_init_sdw()
  ASoC: rt711: Fix return check for devm_regmap_init_sdw()
  ASoC: rt1308-sdw: Fix return check for devm_regmap_init_sdw()
  ASoC: max98373: Fix return check for devm_regmap_init_sdw()
  ASoC: ti: fixup ams_delta_mute() function name
  ASoC: pcm3168a: ignore 0 Hz settings
  ASoC: Intel: tgl_max98373: fix a runtime pm issue in multi-thread case
  ...

Pull iommu fixes from Joerg Roedel:
 "Two fixes for the AMD IOMMU driver:

   - Fix a potential NULL-ptr dereference found by smatch

   - Fix interrupt remapping when a device is assigned to a guest and
     AVIC is enabled"

* tag 'iommu-fixes-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Restore IRTE.RemapEn bit for amd_iommu_activate_guest_mode
  iommu/amd: Fix potential @entry null deref

Pull MTD/SPI NOR fixes from Vignesh Raghavendra:
 "Revert patches that caused non volatile Quad Enable bit to be cleared
  for certain SPI NOR flashes during module remove or during shutdown,
  thus breaking backward compatibility"

Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>

* tag 'mtd/fixes-for-5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
  Revert "mtd: spi-nor: Add capability to disable flash quad mode"
  Revert "mtd: spi-nor: Disable the flash quad mode in spi_nor_restore()"

* pm-cpuidle:
  ACPI: processor: Take over RCU-idle for C3-BM idle
  cpuidle: Allow cpuidle drivers to take over RCU-idle
  ACPI: processor: Use CPUIDLE_FLAG_TLB_FLUSHED
  ACPI: processor: Use CPUIDLE_FLAG_TIMER_STOP

Commit e52d58d5 ("iommu/amd: Use cmpxchg_double() when updating
128-bit IRTE") removed an assumption that modify_irte_ga always set
the valid bit, which requires the callers to set the appropriate value
for the struct irte_ga.valid bit before calling the function.

Similar to the commit 26e495f3 ("iommu/amd: Restore IRTE.RemapEn
bit after programming IRTE"), which is for the function
amd_iommu_deactivate_guest_mode().

The same change is also needed for the amd_iommu_activate_guest_mode().
Otherwise, this could trigger IO_PAGE_FAULT for the VFIO based VMs with
AVIC enabled.

Fixes: e52d58d5

 ("iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE")
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20200916111720.43913-1-suravee.suthikulpanit@amd.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>

After commit 26e495f3 ("iommu/amd: Restore IRTE.RemapEn bit after
programming IRTE"), smatch warns:

	drivers/iommu/amd/iommu.c:3870 amd_iommu_deactivate_guest_mode()
        warn: variable dereferenced before check 'entry' (see line 3867)

Fix this by moving the @valid assignment to after @entry has been checked
for NULL.

Fixes: 26e495f3

 ("iommu/amd: Restore IRTE.RemapEn bit after programming IRTE")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20200910171621.12879-1-joao.m.martins@oracle.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>

Pull percpu fix from Dennis Zhou:
 "This is a fix for the first chunk size calculation where the variable
  length array incorrectly used the number of longs instead of bytes of
  longs.

  This came in as a code fix and not a bug report, so I don't think it
  was widely problematic. I believe it worked out due to it being
  memblock memory and alignment requirements working in our favor"

* 'for-5.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
  percpu: fix first chunk size calculation for populated bitmap

Pull drm fixes from Dave Airlie:
 "A bunch of small fixes, some of the i915 ones have been out for a
  while and got better commit msg explaining some better reasoning
  behind them (hopefully this trend continues).

  Otherwise there a few AMD related ones mostly small, one radeon PLL
  regression fix and a bunch of small mediatek fixes.

  amdgpu:
   - Sienna Cichlid fixes
   - Navy Flounder fixes
   - DC fixes

  amdkfd:
   - Fix a GPU reset crash
   - Fix a memory leak

  radeon:
   - Revert a PLL fix that broke other boards

  i915:
   - Avoid exposing a partially constructed context
   - Use RCU instead of mutex for context termination list iteration
   - Avoid data race reported by KCSAN
   - Filter wake_flags passed to default_wake_function

  mediatek:
   - Fix scrolling of panel
   - Remove duplicated include
   - Use CPU when fail to get cmdq event
   - Add missing put_device() call"

* tag 'drm-fixes-2020-09-18' of git://anongit.freedesktop.org/drm/drm: (21 commits)
  drm/amd/display: Don't log hdcp module warnings in dmesg
  drm/amdgpu: declare ta firmware for navy_flounder
  drm/mediatek: Add missing put_device() call in mtk_hdmi_dt_parse_pdata()
  drm/mediatek: Add missing put_device() call in mtk_drm_kms_init()
  drm/mediatek: Add exception handing in mtk_drm_probe() if component init fail
  drm/mediatek: Add missing put_device() call in mtk_ddp_comp_init()
  drm/mediatek: Use CPU when fail to get cmdq event
  drm/mediatek: Remove duplicated include
  drm/i915: Filter wake_flags passed to default_wake_function
  drm/i915: Be wary of data races when reading the active execlists
  drm/i915/gem: Reduce context termination list iteration guard to RCU
  drm/i915/gem: Delay tracking the GEM context until it is registered
  drm/amdgpu/dc: Require primary plane to be enabled whenever the CRTC is
  drm/radeon: revert "Prefer lower feedback dividers"
  drm/amdgpu: Include sienna_cichlid in USBC PD FW support.
  drm/amd/display: update nv1x stutter latencies
  drm/amd/display: Don't use DRM_ERROR() for DTM add topology
  drm/amd/pm: support runtime pptable update for sienna_cichlid etc.
  drm/amdkfd: fix a memory leak issue
  drm/kfd: fix a system crash issue during GPU recovery
  ...

Merge tag 'mediatek-drm-fixes-5.9' of https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux

 into drm-fixes

Mediatek DRM Fixes for Linux 5.9

1. Fix scrolling of panel
2. Remove duplicated include
3. Use CPU when fail to get cmdq event
4. Add missing put_device() call

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200916231724.30571-1-chunkuang.hu@kernel.org

Merge tag 'drm-intel-fixes-2020-09-17' of ssh://git.freedesktop.org/git/drm/drm-intel

 into drm-fixes

drm/i915 fixes for v5.9-rc6:
- Avoid exposing a partially constructed context
- Use RCU instead of mutex for context termination list iteration
- Avoid data race reported by KCSAN
- Filter wake_flags passed to default_wake_function

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87y2l8vlj3.fsf@intel.com

Merge tag 'amd-drm-fixes-5.9-2020-09-17' of git://people.freedesktop.org/~agd5f/linux

 into drm-fixes

amd-drm-fixes-5.9-2020-09-17:

amdgpu:
- Sienna Cichlid fixes
- Navy Flounder fixes
- DC fixes

amdkfd:
- Fix a GPU reset crash
- Fix a memory leak

radeon:
- Revert a PLL fix that broke other boards

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200917043818.3717-1-alexander.deucher@amd.com

Pull MIPS fixes from Thomas Bogendoerfer:
 "Two small fixes for SNI machines"

* tag 'mips_fixes_5.9_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: SNI: Fix spurious interrupts
  MIPS: SNI: Fix MIPS_L1_CACHE_SHIFT

Variable populated, which is a member of struct pcpu_chunk, is used as a
unit of size of unsigned long.
However, size of populated is miscounted. So, I fix this minor part.

Fixes: 8ab16c43

 ("percpu: change the number of pages marked in the first_chunk pop bitmap")
Cc: <stable@vger.kernel.org> # 4.14+
Signed-off-by: Sunghyun Jin <mcsmonk@gmail.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>

Commit 2a9127fc ("mm: rewrite wait_on_page_bit_common() logic") made
the page locking entirely fair, in that if a waiter came in while the
lock was held, the lock would be transferred to the lockers strictly in
order.

That was intended to finally get rid of the long-reported watchdog
failures that involved the page lock under extreme load, where a process
could end up waiting essentially forever, as other page lockers stole
the lock from under it.

It also improved some benchmarks, but it ended up causing huge
performance regressions on others, simply because fair lock behavior
doesn't end up giving out the lock as aggressively, causing better
worst-case latency, but potentially much worse average latencies and
throughput.

Instead of reverting that change entirely, this introduces a controlled
amount of unfairness, with a sysctl knob to tune it if somebody needs
to.  But the default value should hopefully be good for any normal load,
allowing a few rounds of lock stealing, but enforcing the strict
ordering before the lock has been stolen too many times.

There is also a hint from Matthieu Baerts that the fair page coloring
may end up exposing an ABBA deadlock that is hidden by the usual
optimistic lock stealing, and while the unfairness doesn't fix the
fundamental issue (and I'm still looking at that), it avoids it in
practice.

The amount of unfairness can be modified by writing a new value to the
'sysctl_page_lock_unfairness' variable (default value of 5, exposed
through /proc/sys/vm/page_lock_unfairness), but that is hopefully
something we'd use mainly for debugging rather than being necessary for
any deep system tuning.

This whole issue has exposed just how critical the page lock can be, and
how contended it gets under certain locks.  And the main contention
doesn't really seem to be anything related to IO (which was the origin
of this lock), but for things like just verifying that the page file
mapping is stable while faulting in the page into a page table.

Link: https://lore.kernel.org/linux-fsdevel/ed8442fd-6f54-dd84-cd4a-941e8b7ee603@MichaelLarabel.com/
Link: https://www.phoronix.com/scan.php?page=article&item=linux-50-59&num=1
Link: https://lore.kernel.org/linux-fsdevel/c560a38d-8313-51fb-b1ec-e904bd8836bc@tessares.net/


Reported-and-tested-by: Michael Larabel <Michael@michaellarabel.com>
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Steal time initialization requires mapping a memory region which
invokes a memory allocation. Doing this at CPU starting time results
in the following trace when CONFIG_DEBUG_ATOMIC_SLEEP is enabled:

BUG: sleeping function called from invalid context at mm/slab.h:498
in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, name: swapper/1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5+ #1
Call trace:
 dump_backtrace+0x0/0x208
 show_stack+0x1c/0x28
 dump_stack+0xc4/0x11c
 ___might_sleep+0xf8/0x130
 __might_sleep+0x58/0x90
 slab_pre_alloc_hook.constprop.101+0xd0/0x118
 kmem_cache_alloc_node_trace+0x84/0x270
 __get_vm_area_node+0x88/0x210
 get_vm_area_caller+0x38/0x40
 __ioremap_caller+0x70/0xf8
 ioremap_cache+0x78/0xb0
 memremap+0x9c/0x1a8
 init_stolen_time_cpu+0x54/0xf0
 cpuhp_invoke_callback+0xa8/0x720
 notify_cpu_starting+0xc8/0xd8
 secondary_start_kernel+0x114/0x180
CPU1: Booted secondary processor 0x0000000001 [0x431f0a11]

However we don't need to initialize steal time at CPU starting time.
We can simply wait until CPU online time, just sacrificing a bit of
accuracy by returning zero for steal time until we know better.

While at it, add __init to the functions that are only called by
pv_time_init() which is __init.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Fixes: e0685fa2

 ("arm64: Retrieve stolen time as paravirtualized guest")
Cc: stable@vger.kernel.org
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20200916154530.40809-1-drjones@redhat.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Running the eBPF test_verifier leads to random errors looking like this:

[ 6525.735488] Unexpected kernel BRK exception at EL1
[ 6525.735502] Internal error: ptrace BRK handler: f2000100 [#1] SMP
[ 6525.741609] Modules linked in: nls_utf8 cifs libdes libarc4 dns_resolver fscache binfmt_misc nls_ascii nls_cp437 vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher ghash_ce gf128mul efi_pstore sha2_ce sha256_arm64 sha1_ce evdev efivars efivarfs ip_tables x_tables autofs4 btrfs blake2b_generic xor xor_neon zstd_compress raid6_pq libcrc32c crc32c_generic ahci xhci_pci libahci xhci_hcd igb libata i2c_algo_bit nvme realtek usbcore nvme_core scsi_mod t10_pi netsec mdio_devres of_mdio gpio_keys fixed_phy libphy gpio_mb86s7x
[ 6525.787760] CPU: 3 PID: 7881 Comm: test_verifier Tainted: G        W         5.9.0-rc1+ #47
[ 6525.796111] Hardware name: Socionext SynQuacer E-series DeveloperBox, BIOS build #1 Jun  6 2020
[ 6525.804812] pstate: 20000005 (nzCv daif -PAN -UAO BTYPE=--)
[ 6525.810390] pc : bpf_prog_c3d01833289b6311_F+0xc8/0x9f4
[ 6525.815613] lr : bpf_prog_d53bb52e3f4483f9_F+0x38/0xc8c
[ 6525.820832] sp : ffff8000130cbb80
[ 6525.824141] x29: ffff8000130cbbb0 x28: 0000000000000000
[ 6525.829451] x27: 000005ef6fcbf39b x26: 0000000000000000
[ 6525.834759] x25: ffff8000130cbb80 x24: ffff800011dc7038
[ 6525.840067] x23: ffff8000130cbd00 x22: ffff0008f624d080
[ 6525.845375] x21: 0000000000000001 x20: ffff800011dc7000
[ 6525.850682] x19: 0000000000000000 x18: 0000000000000000
[ 6525.855990] x17: 0000000000000000 x16: 0000000000000000
[ 6525.861298] x15: 0000000000000000 x14: 0000000000000000
[ 6525.866606] x13: 0000000000000000 x12: 0000000000000000
[ 6525.871913] x11: 0000000000000001 x10: ffff8000000a660c
[ 6525.877220] x9 : ffff800010951810 x8 : ffff8000130cbc38
[ 6525.882528] x7 : 0000000000000000 x6 : 0000009864cfa881
[ 6525.887836] x5 : 00ffffffffffffff x4 : 002880ba1a0b3e9f
[ 6525.893144] x3 : 0000000000000018 x2 : ffff8000000a4374
[ 6525.898452] x1 : 000000000000000a x0 : 0000000000000009
[ 6525.903760] Call trace:
[ 6525.906202]  bpf_prog_c3d01833289b6311_F+0xc8/0x9f4
[ 6525.911076]  bpf_prog_d53bb52e3f4483f9_F+0x38/0xc8c
[ 6525.915957]  bpf_dispatcher_xdp_func+0x14/0x20
[ 6525.920398]  bpf_test_run+0x70/0x1b0
[ 6525.923969]  bpf_prog_test_run_xdp+0xec/0x190
[ 6525.928326]  __do_sys_bpf+0xc88/0x1b28
[ 6525.932072]  __arm64_sys_bpf+0x24/0x30
[ 6525.935820]  el0_svc_common.constprop.0+0x70/0x168
[ 6525.940607]  do_el0_svc+0x28/0x88
[ 6525.943920]  el0_sync_handler+0x88/0x190
[ 6525.947838]  el0_sync+0x140/0x180
[ 6525.951154] Code: d4202000 d4202000 d4202000 d4202000 (d4202000)
[ 6525.957249] ---[ end trace cecc3f93b14927e2 ]---

The reason is the offset[] creation and later usage, while building
the eBPF body. The code currently omits the first instruction, since
build_insn() will increase our ctx->idx before saving it.
That was fine up until bounded eBPF loops were introduced. After that
introduction, offset[0] must be the offset of the end of prologue which
is the start of the 1st insn while, offset[n] holds the
offset of the end of n-th insn.

When "taken loop with back jump to 1st insn" test runs, it will
eventually call bpf2a64_offset(-1, 2, ctx). Since negative indexing is
permitted, the current outcome depends on the value stored in
ctx->offset[-1], which has nothing to do with our array.
If the value happens to be 0 the tests will work. If not this error
triggers.

commit 7c2e988f ("bpf: fix x64 JIT code generation for jmp to 1st insn")
fixed an indentical bug on x86 when eBPF bounded loops were introduced.

So let's fix it by creating the ctx->offset[] differently. Track the
beginning of instruction and account for the extra instruction while
calculating the arm instruction offsets.

Fixes: 2589726d

 ("bpf: introduce bounded loops")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: Jiri Olsa <jolsa@kernel.org>
Co-developed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Co-developed-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200917084925.177348-1-ilias.apalodimas@linaro.org


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

[Why]
DTM topology updates happens by default now. This results in DTM
warnings when hdcp is not even being enabled. This spams the dmesg
and doesn't effect normal display functionality so it is better to log it
using DRM_DEBUG_KMS()

[How]
Change the DRM_WARN() to DRM_DEBUG_KMS()

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

The firmware provided via MODULE_FIRMWARE appears in the
module information. External tools(eg. dracut) may use the
list of fw files to include them as appropriate in an initramfs,
thus missing declaration will lead to request firmware failure
in boot time.

Signed-off-by: Jiansong Chen <Jiansong.Chen@amd.com>
Reviewed-by: Tianci Yin <tianci.yin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

if of_find_device_by_node() succeed, mtk_drm_kms_init() doesn't have
a corresponding put_device(). Thus add jump target to fix the exception
handling for this function implementation.

Fixes: 8f83f268

 ("drm/mediatek: Add HDMI support")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

if of_find_device_by_node() succeed, mtk_drm_kms_init() doesn't have
a corresponding put_device(). Thus add jump target to fix the exception
handling for this function implementation.

Fixes: 119f5173

 ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

mtk_ddp_comp_init() is called in a loop in mtk_drm_probe(), if it
fail, previous successive init component is not proccessed.

Thus uninitialize valid component and put their device if component
init failed.

Fixes: 119f5173

 ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

if of_find_device_by_node() succeed, mtk_ddp_comp_init() doesn't have
a corresponding put_device(). Thus add put_device() to fix the exception
handling for this function implementation.

Fixes: d0afe37f

 ("drm/mediatek: support CMDQ interface in ddp component")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

Even though cmdq client is created successfully, without the cmdq event,
cmdq could not work correctly, so use CPU when fail to get cmdq event.

Fixes: 60fa8c13

 ("drm/mediatek: Move gce event property to mutex device node")
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

Remove mtk_drm_ddp.h which is included more than once

Fixes: 9aef5867

 ("drm/mediatek: drop use of drmP.h")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

On A20R machines the interrupt pending bits in cause register need to be
updated by requesting the chipset to do it. This needs to be done to
find the interrupt cause and after interrupt service. In
commit 0b888c7f ("MIPS: SNI: Convert to new irq_chip functions") the
function to do after service update got lost, which caused spurious
interrupts.

Fixes: 0b888c7f

 ("MIPS: SNI: Convert to new irq_chip functions")
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Merge tag 'perf-tools-fixes-for-v5.9-2020-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Set PERF_SAMPLE_PERIOD if attr->freq is set.

 - Remove trailing commas from AMD JSON vendor event files.

 - Don't clear event's period if set by a event definition term.

 - Leader sampling shouldn't clear sample period in 'perf test'.

 - Fix the "signal" test inline assembly when built with DEBUG=1.

 - Fix memory leaks detected by ASAN, some in normal paths, some in
   error paths.

 - Fix 2 memory sanitizer warnings in 'perf bench'.

 - Fix the ratio comments of miss-events in 'perf stat'.

 - Prevent override of attr->sample_period for libpfm4 events.

 - Sync kvm.h and in.h headers with the kernel sources.

* tag 'perf-tools-fixes-for-v5.9-2020-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf stat: Fix the ratio comments of miss-events
  perf test: Free formats for perf pmu parse test
  perf metric: Do not free metric when failed to resolve
  perf metric: Free metric when it failed to resolve
  perf metric: Release expr_parse_ctx after testing
  perf test: Fix memory leaks in parse-metric test
  perf parse-event: Fix memory leak in evsel->unit
  perf evlist: Fix cpu/thread map leak
  perf metric: Fix some memory leaks - part 2
  perf metric: Fix some memory leaks
  perf test: Free aliases for PMU event map aliases test
  perf vendor events amd: Remove trailing commas
  perf test: Leader sampling shouldn't clear sample period
  perf record: Don't clear event's period if set by a term
  tools headers UAPI: update linux/in.h copy
  tools headers UAPI: Sync kvm.h headers with the kernel sources
  perf record: Prevent override of attr->sample_period for libpfm4 events
  perf record: Set PERF_RECORD_PERIOD if attr->freq is set.
  perf bench: Fix 2 memory sanitizer warnings
  perf test: Fix the "signal" test inline assembly

Pull clk driver fixes from Stephen Boyd:
 "A handful of clk driver fixes. Mostly they're for error paths or
  improper memory allocations sizes. Nothing as exciting as a wildfire"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: qcom: lpass: Correct goto target in lpass_core_sc7180_probe()
  clk: versatile: Add of_node_put() before return statement
  clk: bcm: dvp: Select the reset framework
  clk: rockchip: Fix initialization of mux_pll_src_4plls_p
  clk: davinci: Use the correct size when allocating memory

Max's and Shravan's usernames were changed while @mellanox.com emails
were transferred to be @nvidia.com.

Fixes: f6da70d9

 ("MAINTAINERS: Update Mellanox and Cumulus Network addresses to new domain")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>