Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.10:

   - regression fix for a boot failure on some 32-bit machines.

   - fix for host crashes in the KVM system reset handling.

   - fix for a possible oops in the KVM XIVE interrupt handling on
     Power9.

   - fix for host crashes triggerable via the KVM emulated MMIO handling
     when running HPT guests.

   - a couple of small build fixes.

  Thanks to Andreas Schwab, Cédric Le Goater, Christophe Leroy, Erhard
  Furtner, Greg Kurz, Greg Kurz, Németh Márton, Nicholas Piggin, Nick
  Desaulniers, Serge Belyshev, and Stephen Rothwell"

* tag 'powerpc-5.10-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Fix allnoconfig build since uaccess flush
  powerpc/64s/exception: KVM Fix for host DSI being taken in HPT guest MMU context
  powerpc: Drop -me200 addition to build flags
  KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page
  powerpc/64s: Fix KVM system reset handling when CONFIG_PPC_PSERIES=y
  powerpc/32s: Use relocation offset when setting early hash table

Pull arm64 fixes from Will Deacon:
 "The main changes are relating to our handling of access/dirty bits,
  where our low-level page-table helpers could lead to stale young
  mappings and loss of the dirty bit in some cases (the latter has not
  been observed in practice, but could happen when clearing "soft-dirty"
  if we enabled that). These were posted as part of a larger series, but
  the rest of that is less urgent and needs a v2 which I'll get to
  shortly.

  In other news, we've now got a set of fixes to resolve the
  lockdep/tracing problems that have been plaguing us for a while, but
  they're still a bit "fresh" and I plan to send them to you next week
  after we've got some more confidence in them (although initial CI
  results look good).

  Summary:

   - Fix kerneldoc warnings generated by ACPI IORT code

   - Fix pte_accessible() so that access flag is ignored

   - Fix missing header #include

   - Fix loss of software dirty bit across pte_wrprotect() when HW DBM
     is enabled"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: pgtable: Ensure dirty bit is preserved across pte_wrprotect()
  arm64: pgtable: Fix pte_accessible()
  ACPI/IORT: Fix doc warnings in iort.c
  arm64/fpsimd: add <asm/insn.h> to <asm/kprobes.h> to fix fpsimd build

Pull iommu fixes from Will Deacon:
 "Here's another round of IOMMU fixes for -rc6 consisting mainly of a
  bunch of independent driver fixes. Thomas agreed for me to take the
  x86 'tboot' fix here, as it fixes a regression introduced by a vt-d
  change.

   - Fix intel iommu driver when running on devices without VCCAP_REG

   - Fix swiotlb and "iommu=pt" interaction under TXT (tboot)

   - Fix missing return value check during device probe()

   - Fix probe ordering for Qualcomm SMMU implementation

   - Ensure page-sized mappings are used for AMD IOMMU buffers with SNP
     RMP"

* tag 'iommu-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  iommu/vt-d: Don't read VCCAP register unless it exists
  x86/tboot: Don't disable swiotlb when iommu is forced on
  iommu: Check return of __iommu_attach_device()
  arm-smmu-qcom: Ensure the qcom_scm driver has finished probing
  iommu/amd: Enforce 4k mapping for certain IOMMU data structures

Pull printk fixes from Petr Mladek:

 - do not lose trailing newline in pr_cont() calls

 - two trivial fixes for a dead store and a config description

* tag 'printk-for-5.10-rc6-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: finalize records with trailing newlines
  printk: remove unneeded dead-store assignment
  init/Kconfig: Fix CPU number in LOG_CPU_MAX_BUF_SHIFT description

Pull writeback fix from Jan Kara:
 "A fix of possible missing string termination in writeback tracepoints"

* tag 'writeback_for_v5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  trace: fix potenial dangerous pointer

Any record with a trailing newline (LOG_NEWLINE flag) cannot
be continued because the newline has been stripped and will
not be visible if the message is appended. This was already
handled correctly when committing in log_output() but was
not handled correctly when committing in log_store().

Fixes: f5f022e5 ("printk: reimplement log_cont using record extension")
Link: https://lore.kernel.org/r/20201126114836.14750-1-john.ogness@linutronix.deReported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>

Pull power management fix from Rafael Wysocki:
 "Fix a recently introduced build issue in the cpufreq SCMI driver
  (Sudeep Holla)"

* tag 'pm-5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: scmi: Fix build for !CONFIG_COMMON_CLK

0day reported one -22.7% regression for will-it-scale page_fault2
case [1] on a 4 sockets 144 CPU platform, and bisected to it to be
caused by Waiman's optimization (commit bd0b230f) of saving one
'struct page_counter' space for 'struct mem_cgroup'.

Initially we thought it was due to the cache alignment change introduced
by the patch, but further debug shows that it is due to some hot data
members ('vmstats_local', 'vmstats_percpu', 'vmstats') sit in 2 adjacent
cacheline (2N and 2N+1 cacheline), and when adjacent cache line prefetch
is enabled, it triggers an "extended level" of cache false sharing for
2 adjacent cache lines.

So exchange the 2 member blocks, while keeping mostly the original
cache alignment, which can restore and even enhance the performance,
and save 64 bytes of space for 'struct mem_cgroup' (from 2880 to 2816,
with 0day's default RHEL-8.3 kernel config)

[1]. https://lore.kernel.org/lkml/20201102091543.GM31092@shao2-debian/

Fixes: bd0b230f ("mm/memcg: unify swap and memsw page counters")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

My virtual IOMMU implementation is whining that the guest is reading a
register that doesn't exist. Only read the VCCAP_REG if the corresponding
capability is set in ECAP_REG to indicate that it actually exists.

Fixes: 3375303e ("iommu/vt-d: Add custom allocator for IOASID")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Cc: stable@vger.kernel.org # v5.7+
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/de32b150ffaa752e0cff8571b17dfb1213fbe71c.camel@infradead.orgSigned-off-by: Will Deacon <will@kernel.org>

Pull media fixes from Mauro Carvalho Chehab:

 - a rand Kconfig fixup for mtk-vcodec

 - a fix at h264 handling at cedrus codec driver

 - some warning fixes when config PM is not enabled at marvell-ccic

 - two fixes at venus codec driver: one related to codec profile and the
   other one related to a bad error path which causes an OOPS on module
   re-bind

* tag 'media/v5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: venus: pm_helpers: Fix kernel module reload
  media: venus: venc: Fix setting of profile and level
  media: cedrus: h264: Fix check for presence of scaling matrix
  media: media/platform/marvell-ccic: fix warnings when CONFIG_PM is not enabled
  media: mtk-vcodec: fix build breakage when one of VPU or SCP is enabled
  media: mtk-vcodec: move firmware implementations into their own files

After commit 327d5b2f ("iommu/vt-d: Allow 32bit devices to uses DMA
domain"), swiotlb could also be used for direct memory access if IOMMU
is enabled but a device is configured to pass through the DMA translation.
Keep swiotlb when IOMMU is forced on, otherwise, some devices won't work
if "iommu=pt" kernel parameter is used.

Fixes: 327d5b2f ("iommu/vt-d: Allow 32bit devices to uses DMA domain")
Reported-and-tested-by: Adrian Huang <ahuang12@lenovo.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201125014124.4070776-1-baolu.lu@linux.intel.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=210237Signed-off-by: Will Deacon <will@kernel.org>

The bdi_dev_name() returns a char [64], and
the __entry->name is a char [32].

It maybe dangerous to TP_printk("%s", __entry->name)
after the strncpy().

CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201124165205.GA23937@rlkAcked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Pull cifs fixes from Steve French:
 "Four smb3 fixes for stable: one fixes a memleak, the other three
  address a problem found with decryption offload that can cause a use
  after free"

* tag '5.10-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: Handle error case during offload read path
  smb3: Avoid Mid pending list corruption
  smb3: Call cifs reconnect from demultiplex thread
  cifs: fix a memleak with modefromsid

Twice now, when exercising ext4 looped on shmem huge pages, I have crashed
on the PF_ONLY_HEAD check inside PageWaiters(): ext4_finish_bio() calling
end_page_writeback() calling wake_up_page() on tail of a shmem huge page,
no longer an ext4 page at all.

The problem is that PageWriteback is not accompanied by a page reference
(as the NOTE at the end of test_clear_page_writeback() acknowledges): as
soon as TestClearPageWriteback has been done, that page could be removed
from page cache, freed, and reused for something else by the time that
wake_up_page() is reached.

https://lore.kernel.org/linux-mm/20200827122019.GC14765@casper.infradead.org/
Matthew Wilcox suggested avoiding or weakening the PageWaiters() tail
check; but I'm paranoid about even looking at an unreferenced struct page,
lest its memory might itself have already been reused or hotremoved (and
wake_up_page_bit() may modify that memory with its ClearPageWaiters()).

Then on crashing a second time, realized there's a stronger reason against
that approach.  If my testing just occasionally crashes on that check,
when the page is reused for part of a compound page, wouldn't it be much
more common for the page to get reused as an order-0 page before reaching
wake_up_page()?  And on rare occasions, might that reused page already be
marked PageWriteback by its new user, and already be waited upon?  What
would that look like?

It would look like BUG_ON(PageWriteback) after wait_on_page_writeback()
in write_cache_pages() (though I have never seen that crash myself).

Matthew Wilcox explaining this to himself:
 "page is allocated, added to page cache, dirtied, writeback starts,

  --- thread A ---
  filesystem calls end_page_writeback()
        test_clear_page_writeback()
  --- context switch to thread B ---
  truncate_inode_pages_range() finds the page, it doesn't have writeback set,
  we delete it from the page cache.  Page gets reallocated, dirtied, writeback
  starts again.  Then we call write_cache_pages(), see
  PageWriteback() set, call wait_on_page_writeback()
  --- context switch back to thread A ---
  wake_up_page(page, PG_writeback);
  ... thread B is woken, but because the wakeup was for the old use of
  the page, PageWriteback is still set.

  Devious"

And prior to 2a9127fc ("mm: rewrite wait_on_page_bit_common() logic")
this would have been much less likely: before that, wake_page_function()'s
non-exclusive case would stop walking and not wake if it found Writeback
already set again; whereas now the non-exclusive case proceeds to wake.

I have not thought of a fix that does not add a little overhead: the
simplest fix is for end_page_writeback() to get_page() before calling
test_clear_page_writeback(), then put_page() after wake_up_page().

Was there a chance of missed wakeups before, since a page freed before
reaching wake_up_page() would have PageWaiters cleared?  I think not,
because each waiter does hold a reference on the page.  This bug comes
when the old use of the page, the one we do TestClearPageWriteback on,
had *no* waiters, so no additional page reference beyond the page cache
(and whoever racily freed it).  The reuse of the page has a waiter
holding a reference, and its own PageWriteback set; but the belated
wake_up_page() has woken the reuse to hit that BUG_ON(PageWriteback).

Reported-by: syzbot+3622cea378100f45d59f@syzkaller.appspotmail.com
Reported-by: Qian Cai <cai@lca.pw>
Fixes: 2a9127fc ("mm: rewrite wait_on_page_bit_common() logic")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull s390 fix from Heiko Carstens:
 "Disable interrupts when restoring fpu and vector registers, otherwise
  KVM guests might see corrupted register contents"

* tag 's390-5.10-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: fix fpu restore in entry.S

Pull ARC fixes from Vineet Gupta:
 "A couple more stack unwinder related fixes:

   - More stack unwinding updates

   - Misc minor fixes"

* tag 'arc-5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: stack unwinding: reorganize how initial register state setup
  ARC: stack unwinding: don't assume non-current task is sleeping
  ARC: mm: fix spelling mistakes
  ARC: bitops: Remove unecessary operation and value

Pull Hyper-V fix from Wei Liu:
 "One patch from Dexuan to fix VRAM cache type in Hyper-V framebuffer
  driver"

* tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  video: hyperv_fb: Fix the cache type when mapping the VRAM

With hardware dirty bit management, calling pte_wrprotect() on a writable,
dirty PTE will lose the dirty state and return a read-only, clean entry.

Move the logic from ptep_set_wrprotect() into pte_wrprotect() to ensure that
the dirty bit is preserved for writable entries, as this is required for
soft-dirty bit management if we enable it in the future.

Cc: <stable@vger.kernel.org>
Fixes: 2f4b829c ("arm64: Add support for hardware updates of the access and dirty pte bits")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201120143557.6715-3-will@kernel.orgSigned-off-by: Will Deacon <will@kernel.org>

pte_accessible() is used by ptep_clear_flush() to figure out whether TLB
invalidation is necessary when unmapping pages for reclaim. Although our
implementation is correct according to the architecture, returning true
only for valid, young ptes in the absence of racing page-table
modifications, this is in fact flawed due to lazy invalidation of old
ptes in ptep_clear_flush_young() where we elide the expensive DSB
instruction for completing the TLB invalidation.

Rather than penalise the aging path, adjust pte_accessible() to return
true for any valid pte, even if the access flag is cleared.

Cc: <stable@vger.kernel.org>
Fixes: 76c714be ("arm64: pgtable: implement pte_accessible()")
Reported-by: Yu Zhao <yuzhao@google.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201120143557.6715-2-will@kernel.orgSigned-off-by: Will Deacon <will@kernel.org>

Currently iommu_create_device_direct_mappings() is called
without checking the return of __iommu_attach_device(). This
may result in failures in iommu driver if dev attach returns
error.

Fixes: ce574c27 ("iommu: Move iommu_group_create_direct_mappings() out of iommu_group_add_device()")
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20201119165846.34180-1-shameerali.kolothum.thodi@huawei.comSigned-off-by: Will Deacon <will@kernel.org>

Robin Murphy pointed out that if the arm-smmu driver probes before
the qcom_scm driver, we may call qcom_scm_qsmmu500_wait_safe_toggle()
before the __scm is initialized.

Now, getting this to happen is a bit contrived, as in my efforts it
required enabling asynchronous probing for both drivers, moving the
firmware dts node to the end of the dtsi file, as well as forcing a
long delay in the qcom_scm_probe function.

With those tweaks we ran into the following crash:
[    2.631040] arm-smmu 15000000.iommu:         Stage-1: 48-bit VA -> 48-bit IPA
[    2.633372] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
...
[    2.633402] [0000000000000000] user address but active_mm is swapper
[    2.633409] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[    2.633415] Modules linked in:
[    2.633427] CPU: 5 PID: 117 Comm: kworker/u16:2 Tainted: G        W         5.10.0-rc1-mainline-00025-g272a618fc36-dirty #3971
[    2.633430] Hardware name: Thundercomm Dragonboard 845c (DT)
[    2.633448] Workqueue: events_unbound async_run_entry_fn
[    2.633456] pstate: 80c00005 (Nzcv daif +PAN +UAO -TCO BTYPE=--)
[    2.633465] pc : qcom_scm_qsmmu500_wait_safe_toggle+0x78/0xb0
[    2.633473] lr : qcom_smmu500_reset+0x58/0x78
[    2.633476] sp : ffffffc0105a3b60
...
[    2.633567] Call trace:
[    2.633572]  qcom_scm_qsmmu500_wait_safe_toggle+0x78/0xb0
[    2.633576]  qcom_smmu500_reset+0x58/0x78
[    2.633581]  arm_smmu_device_reset+0x194/0x270
[    2.633585]  arm_smmu_device_probe+0xc94/0xeb8
[    2.633592]  platform_drv_probe+0x58/0xa8
[    2.633597]  really_probe+0xec/0x398
[    2.633601]  driver_probe_device+0x5c/0xb8
[    2.633606]  __driver_attach_async_helper+0x64/0x88
[    2.633610]  async_run_entry_fn+0x4c/0x118
[    2.633617]  process_one_work+0x20c/0x4b0
[    2.633621]  worker_thread+0x48/0x460
[    2.633628]  kthread+0x14c/0x158
[    2.633634]  ret_from_fork+0x10/0x18
[    2.633642] Code: a9034fa0 d0007f73 29107fa0 91342273 (f9400020)

To avoid this, this patch adds a check on qcom_scm_is_available() in
the qcom_smmu_impl_init() function, returning -EPROBE_DEFER if its
not ready.

This allows the driver to try to probe again later after qcom_scm has
finished probing.
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Maulik Shah <mkshah@codeaurora.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: iommu@lists.linux-foundation.org
Cc: linux-arm-msm <linux-arm-msm@vger.kernel.org>
Link: https://lore.kernel.org/r/20201112220520.48159-1-john.stultz@linaro.orgSigned-off-by: Will Deacon <will@kernel.org>

AMD IOMMU requires 4k-aligned pages for the event log, the PPR log,
and the completion wait write-back regions. However, when allocating
the pages, they could be part of large mapping (e.g. 2M) page.
This causes #PF due to the SNP RMP hardware enforces the check based
on the page level for these data structures.

So, fix by calling set_memory_4k() on the allocated pages.

Fixes: c69d89af ("iommu/amd: Use 4K page for completion wait write-back semaphore")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Link: https://lore.kernel.org/r/20201105145832.3065-1-suravee.suthikulpanit@amd.comSigned-off-by: Will Deacon <will@kernel.org>

Pull SCMI cpufreq driver fix for 5.10-rc6 from Viresh Kumar:

"This fixes a build issues with SCMI cpufreq driver in the
 !CONFIG_COMMON_CLK case."

* 'cpufreq/arm/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  cpufreq: scmi: Fix build for !CONFIG_COMMON_CLK

Fix following warnings caused by mismatch between
function parameters and function comments.

drivers/acpi/arm64/iort.c:55: warning: Function parameter or member 'iort_node' not described in 'iort_set_fwnode'
drivers/acpi/arm64/iort.c:55: warning: Excess function parameter 'node' description in 'iort_set_fwnode'
drivers/acpi/arm64/iort.c:682: warning: Function parameter or member 'id' not described in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:682: warning: Function parameter or member 'bus_token' not described in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:682: warning: Excess function parameter 'req_id' description in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:1142: warning: Function parameter or member 'dma_size' not described in 'iort_dma_setup'
drivers/acpi/arm64/iort.c:1142: warning: Excess function parameter 'size' description in 'iort_dma_setup'
drivers/acpi/arm64/iort.c:1534: warning: Function parameter or member 'ops' not described in 'iort_add_platform_device'
Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20201014093139.1580-1-shiju.jose@huawei.comSigned-off-by: Will Deacon <will@kernel.org>

Adding <asm/exception.h> brought in <asm/kprobes.h> which uses
<asm/probes.h>, which uses 'pstate_check_t' so the latter needs to
#include <asm/insn.h> for this typedef.

Fixes this build error:

  In file included from arch/arm64/include/asm/kprobes.h:24,
                    from arch/arm64/include/asm/exception.h:11,
                    from arch/arm64/kernel/fpsimd.c:35:
  arch/arm64/include/asm/probes.h:16:2: error: unknown type name 'pstate_check_t'
      16 |  pstate_check_t *pstate_cc;

Fixes: c6b90d5c ("arm64/fpsimd: Fix missing-prototypes in fpsimd.c")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/20201123044510.9942-1-rdunlap@infradead.orgSigned-off-by: Will Deacon <will@kernel.org>

We need to disable interrupts in load_fpu_regs(). Otherwise an
interrupt might come in after the registers are loaded, but before
CIF_FPU is cleared in load_fpu_regs(). When the interrupt returns,
CIF_FPU will be cleared and the registers will never be restored.

The entry.S code usually saves the interrupt state in __SF_EMPTY on the
stack when disabling/restoring interrupts. sie64a however saves the pointer
to the sie control block in __SF_SIE_CONTROL, which references the same
location.  This is non-obvious to the reader. To avoid thrashing the sie
control block pointer in load_fpu_regs(), move the __SIE_* offsets eight
bytes after __SF_EMPTY on the stack.

Cc: <stable@vger.kernel.org> # 5.8
Fixes: 0b0ed657 ("s390: remove critical section cleanup from entry.S")
Reported-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

Using DECLARE_STATIC_KEY_FALSE needs linux/jump_table.h.

Otherwise the build fails with eg:

  arch/powerpc/include/asm/book3s/64/kup-radix.h:66:1: warning: data definition has no type or storage class
     66 | DECLARE_STATIC_KEY_FALSE(uaccess_flush_key);

Fixes: 9a32a7e7 ("powerpc/64s: flush L1D after user accesses")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[mpe: Massage change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201123184016.693fe464@canb.auug.org.au

From Daniel's cover letter:

IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern.

This patch series flushes the L1 cache on kernel entry (patch 2) and after the
kernel performs any user accesses (patch 3). It also adds a self-test and
performs some related cleanups.

Commit 8410e7f3 ("cpufreq: scmi: Fix OPP addition failure with a
dummy clock provider") registers a dummy clock provider using
devm_of_clk_add_hw_provider. These *_hw_provider functions are defined
only when CONFIG_COMMON_CLK=y. One possible fix is to add the Kconfig
dependency, but since we plan to move away from the clock dependency
for scmi cpufreq, it is preferrable to avoid that.

Let us just conditionally compile out the offending call to
devm_of_clk_add_hw_provider. It also uses the variable 'dev' outside
of the #ifdef block to avoid build warning.

Fixes: 8410e7f3 ("cpufreq: scmi: Fix OPP addition failure with a dummy clock provider")
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Pull HID fixes from Jiri Kosina:

 - Various functionality / regression fixes for Logitech devices from
   Hans de Goede

 - Fix for (recently added) GPIO support in mcp2221 driver from Lars
   Povlsen

 - Power management handling fix/quirk in i2c-hid driver for certain
   BIOSes that have strange aproach to power-cycle from Hans de Goede

 - a few device ID additions and device-specific quirks

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
  HID: logitech-dj: Fix Dinovo Mini when paired with a MX5x00 receiver
  HID: logitech-dj: Fix an error in mse_bluetooth_descriptor
  HID: Add Logitech Dinovo Edge battery quirk
  HID: logitech-hidpp: Add HIDPP_CONSUMER_VENDOR_KEYS quirk for the Dinovo Edge
  HID: logitech-dj: Handle quad/bluetooth keyboards with a builtin trackpad
  HID: add HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE for Gamevice devices
  HID: mcp2221: Fix GPIO output handling
  HID: hid-sensor-hub: Fix issue with devices with no report ID
  HID: i2c-hid: Put ACPI enumerated devices in D3 on shutdown
  HID: add support for Sega Saturn
  HID: cypress: Support Varmilo Keyboards' media hotkeys
  HID: ite: Replace ABS_MISC 120/121 events with touchpad on/off keypresses
  HID: logitech-hidpp: Add PID for MX Anywhere 2
  HID: uclogic: Add ID for Trust Flex Design Tablet

Pull scheduler fixes from Thomas Gleixner:
 "A couple of scheduler fixes:

   - Make the conditional update of the overutilized state work
     correctly by caching the relevant flags state before overwriting
     them and checking them afterwards.

   - Fix a data race in the wakeup path which caused loadavg on ARM64
     platforms to become a random number generator.

   - Fix the ordering of the iowaiter accounting operations so it can't
     be decremented before it is incremented.

   - Fix a bug in the deadline scheduler vs. priority inheritance when a
     non-deadline task A has inherited the parameters of a deadline task
     B and then blocks on a non-deadline task C.

     The second inheritance step used the static deadline parameters of
     task A, which are usually 0, instead of further propagating task
     B's parameters. The zero initialized parameters trigger a bug in
     the deadline scheduler"

* tag 'sched-urgent-2020-11-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix priority inheritance with multiple scheduling classes
  sched: Fix rq->nr_iowait ordering
  sched: Fix data-race in wakeup
  sched/fair: Fix overutilized update in enqueue_task_fair()

Pull perf fix from Thomas Gleixner:
 "A single fix for the x86 perf sysfs interfaces which used kobject
  attributes instead of device attributes and therefore making clang's
  control flow integrity checker upset"

* tag 'perf-urgent-2020-11-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: fix sysfs type mismatches

Pull locking fix from Thomas Gleixner:
 "A single fix for lockdep which makes the recursion protection cover
  graph lock/unlock"

* tag 'locking-urgent-2020-11-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Put graph lock/unlock under lock_recursion protection

Pull EFI fixes from Borislav Petkov:
 "Forwarded EFI fixes from Ard Biesheuvel:

   - fix memory leak in efivarfs driver

   - fix HYP mode issue in 32-bit ARM version of the EFI stub when built
     in Thumb2 mode

   - avoid leaking EFI pgd pages on allocation failure"

* tag 'efi-urgent-for-v5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/x86: Free efi_pgd with free_pages()
  efivarfs: fix memory leak in efivarfs_create()
  efi/arm: set HSCTLR Thumb2 bit correctly for HVC calls from HYP

Pull x86 fixes from Borislav Petkov:

 - An IOMMU VT-d build fix when CONFIG_PCI_ATS=n along with a revert of
   same because the proper one is going through the IOMMU tree (Thomas
   Gleixner)

 - An Intel microcode loader fix to save the correct microcode patch to
   apply during resume (Chen Yu)

 - A fix to not access user memory of other processes when dumping
   opcode bytes (Thomas Gleixner)

* tag 'x86_urgent_for_v5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "iommu/vt-d: Take CONFIG_PCI_ATS into account"
  x86/dumpstack: Do not try to access user space code of other tasks
  x86/microcode/intel: Check patch signature before saving microcode for early loading
  iommu/vt-d: Take CONFIG_PCI_ATS into account

Merge misc fixes from Andrew Morton:
 "8 patches.

  Subsystems affected by this patch series: mm (madvise, pagemap,
  readahead, memcg, userfaultfd), kbuild, and vfs"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: fix madvise WILLNEED performance problem
  libfs: fix error cast of negative value in simple_attr_write()
  mm/userfaultfd: do not access vma->vm_mm after calling handle_userfault()
  mm: memcg/slab: fix root memcg vmstats
  mm: fix readahead_page_batch for retry entries
  mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports
  compiler-clang: remove version check for BPF Tracing
  mm/madvise: fix memory leak from process_madvise

Pull staging and IIO fixes from Greg KH:
 "Here are some small Staging and IIO driver fixes for 5.10-rc5. They
  include:

   - IIO fixes for reported regressions and problems

   - new device ids for IIO drivers

   - new device id for rtl8723bs driver

   - staging ralink driver Kconfig dependency fix

   - staging mt7621-pci bus resource fix

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

* tag 'staging-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  iio: accel: kxcjk1013: Add support for KIOX010A ACPI DSM for setting tablet-mode
  iio: accel: kxcjk1013: Replace is_smo8500_device with an acpi_type enum
  docs: ABI: testing: iio: stm32: remove re-introduced unsupported ABI
  iio: light: fix kconfig dependency bug for VCNL4035
  iio/adc: ingenic: Fix AUX/VBAT readings when touchscreen is used
  iio/adc: ingenic: Fix battery VREF for JZ4770 SoC
  staging: rtl8723bs: Add 024c:0627 to the list of SDIO device-ids
  staging: ralink-gdma: fix kconfig dependency bug for DMA_RALINK
  staging: mt7621-pci: avoid to request pci bus resources
  iio: imu: st_lsm6dsx: set 10ms as min shub slave timeout
  counter/ti-eqep: Fix regmap max_register
  iio: adc: stm32-adc: fix a regression when using dma and irq
  iio: adc: mediatek: fix unset field
  iio: cros_ec: Use default frequencies when EC returns invalid information

Pull tty fixes from Greg KH:
 "Here are some small tty/serial fixes for 5.10-rc5 that resolve some
  reported issues:

   - speakup crash when telling the kernel to use a device that isn't
     really there

   - imx serial driver fixes for reported problems

   - ar933x_uart driver fix for probe error handling path

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

* tag 'tty-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: ar933x_uart: disable clk on error handling path in probe
  tty: serial: imx: keep console clocks always on
  speakup: Do not let the line discipline be used several times
  tty: serial: imx: fix potential deadlock