Today the Xen ballooning is done via delayed work in a workqueue. This
might result in workqueue hangups being reported in case of large
amounts of memory are being ballooned in one go (here 16GB):

BUG: workqueue lockup - pool cpus=6 node=0 flags=0x0 nice=0 stuck for 64s!
Showing busy workqueues and worker pools:
workqueue events: flags=0x0
  pwq 12: cpus=6 node=0 flags=0x0 nice=0 active=2/256 refcnt=3
    in-flight: 229:balloon_process
    pending: cache_reap
workqueue events_freezable_power_: flags=0x84
  pwq 12: cpus=6 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
    pending: disk_events_workfn
workqueue mm_percpu_wq: flags=0x8
  pwq 12: cpus=6 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
    pending: vmstat_update
pool 12: cpus=6 node=0 flags=0x0 nice=0 hung=64s workers=3 idle: 2222 43

This can easily be avoided by using a dedicated kernel thread for doing
the ballooning work.
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210827123206.15429-1-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

In cpu_bringup() there is a call of preempt_disable() without a paired
preempt_enable(). This is not needed as interrupts are off initially.
Additionally this will result in early boot messages like:

BUG: scheduling while atomic: swapper/1/0/0x00000002
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210825113158.11716-1-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

An unnecessary "__ref" annotation was removed from the
"drivers/pci/xen_pcifront.c" file. The function where the annotation
was used was "pcifront_backend_changed()", which does not call any
functions annotated as "__*init" nor "__*exit". This makes "__ref"
unnecessary since this annotation is used to make the compiler ignore
section miss-matches when they are not happening here in the first
place.

In addition to the aforementioned change, some code style issues were
fixed in the same file.
Signed-off-by: Sergio Miguéns Iglesias <sergio@lony.xyz>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210830175305.13370-1-sergio@lony.xyzSigned-off-by: Juergen Gross <jgross@suse.com>

Since we have the nice helpers pr_err() and pr_warn(), use them instead
of raw printk().

[jgross@suse.com] Move the "#define pr_fmt" above the #includes in
                  order to avoid build warnings due to redefinition.
Signed-off-by: zhaoxiao <zhaoxiao@uniontech.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210825114111.29009-1-zhaoxiao@uniontech.comSigned-off-by: Juergen Gross <jgross@suse.com>

Use BUG_ON instead of a if condition followed by BUG.

Generated by: scripts/coccinelle/misc/bugon.cocci
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jing Yangyang <jing.yangyang@zte.com.cn>
Reviewed-by: SeongJae Park <sjpark@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210825062451.69998-1-deng.changcheng@zte.com.cnSigned-off-by: Juergen Gross <jgross@suse.com>

Today blkfront will trust the backend to send only sane response data.
In order to avoid privilege escalations or crashes in case of malicious
backends verify the data to be within expected limits. Especially make
sure that the response always references an outstanding request.

Introduce a new state of the ring BLKIF_STATE_ERROR which will be
switched to in case an inconsistency is being detected. Recovering from
this state is possible only via removing and adding the virtual device
again (e.g. via a suspend/resume cycle).

Make all warning messages issued due to valid error responses rate
limited in order to avoid message floods being triggered by a malicious
backend.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-4-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

In order to avoid a malicious backend being able to influence the local
copy of a request build the request locally first and then copy it to
the ring page instead of doing it the other way round as today.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-3-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

In order to avoid problems in case the backend is modifying a response
on the ring page while the frontend has already seen it, just read the
response into a local buffer in one go and then operate on that buffer
only.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-2-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

XENFEAT_gnttab_map_avail_bits is always set in Xen 4.0 and newer.
Remove coding assuming it might be zero.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210730071804.4302-4-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

XENFEAT_mmu_pt_update_preserve_ad is always set in Xen 4.0 and newer.
Remove coding assuming it might be zero.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210730071804.4302-3-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

Linux kernel is not supported to run on Xen versions older than 4.0.

Add tests for required Xen features always being present in Xen 4.0
and newer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210730071804.4302-2-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

Xen PV guests are specifying the highest used PFN via the max_pfn
field in shared_info. This value is used by the Xen tools when saving
or migrating the guest.

Unfortunately this field is misnamed, as in reality it is specifying
the number of pages (including any memory holes) of the guest, so it
is the highest used PFN + 1. Renaming isn't possible, as this is a
public Xen hypervisor interface which needs to be kept stable.

The kernel will set the value correctly initially at boot time, but
when adding more pages (e.g. due to memory hotplug or ballooning) a
real PFN number is stored in max_pfn. This is done when expanding the
p2m array, and the PFN stored there is even possibly wrong, as it
should be the last possible PFN of the just added P2M frame, and not
one which led to the P2M expansion.

Fix that by setting shared_info->max_pfn to the last possible PFN + 1.

Fixes: 98dd166e ("x86/xen/p2m: hint at the last populated P2M entry")
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20210730092622.9973-2-jgross@suse.comSigned-off-by: Juergen Gross <jgross@suse.com>

Pull clk fix from Stephen Boyd:
 "One hotfix for a NULL pointer deref in the Renesas usb clk driver"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: renesas: rcar-usb2-clock-sel: Fix kernel NULL pointer dereference

Pull scheduler fixes from Borislav Petkov:

 - Have get_push_task() check whether current has migration disabled and
   thus avoid useless invocations of the migration thread

 - Rework initialization flow so that all rq->core's are initialized,
   even of CPUs which have not been onlined yet, so that iterating over
   them all works as expected

* tag 'sched_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix get_push_task() vs migrate_disable()
  sched: Fix Core-wide rq->lock for uninitialized CPUs

Pull irq fix from Borislav Petkov:

 - Have msix_mask_all() check a global control which says whether MSI-X
   masking should be done and thus make it usable on Xen-PV too

* tag 'irq_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  PCI/MSI: Skip masking MSI-X on Xen PV

Pull perf fixes from Borislav Petkov:

 - Prevent the amd/power module from being removed while in use

 - Mark AMD IBS as not supporting content exclusion

 - Add a workaround for AMD erratum #1197 where IBS registers might not
   be restored properly after exiting CC6 state

 - Fix a potential truncation of a 32-bit variable due to shifting

 - Read the correct bits describing the number of configurable address
   ranges on Intel PT

* tag 'perf_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd/power: Assign pmu.module
  perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op
  perf/x86/amd/ibs: Work around erratum #1197
  perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32
  perf/x86/intel/pt: Fix mask of num_address_ranges

Pull x86 fixes from Borislav Petkov:

 - Fix build error on RHEL where -Werror=maybe-uninitialized is set.

 - Restore the firmware's IDT when calling EFI boot services and before
   ExitBootServices() has been called. This fixes a boot failure on what
   appears to be a tablet with 32-bit UEFI running a 64-bit kernel.

* tag 'x86_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Fix a maybe-uninitialized build warning treated as error
  x86/efi: Restore Firmware IDT before calling ExitBootServices()

This reverts commit 83af58f8.

It turns out that at least the assembly implementation for strncpy() was
buggy.  Revert the whole commit and return back to the default coding.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The probe was manually passing NULL instead of dev to devm_clk_hw_register.
This caused a Unable to handle kernel NULL pointer dereference error.
Fix this by passing 'dev'.
Signed-off-by: Adam Ford <aford173@gmail.com>
Fixes: a20a40a8 ("clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()")
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Pull SCSI fix from James Bottomley:
 "A single fix for a race introduced by a fix that went into 5.14-rc5"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: core: Fix hang of freezing queue between blocking and running device

Pull USB fixes from Greg KH:
 "Here are a few tiny USB fixes for reported issues with some USB
  drivers.

  These fixes include:

   - gadget driver fixes for regressions

   - tcpm driver fix

   - dwc3 driver fixes

   - xhci renesas firmware loading fix, again.

   - usb serial option driver device id addition

   - usb serial ch341 revert for regression

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

* tag 'usb-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: gadget: u_audio: fix race condition on endpoint stop
  usb: gadget: f_uac2: fixup feedback endpoint stop
  usb: typec: tcpm: Raise vdm_sm_running flag only when VDM SM is running
  usb: renesas-xhci: Prefer firmware loading on unknown ROM state
  usb: dwc3: gadget: Stop EP0 transfers during pullup disable
  usb: dwc3: gadget: Fix dwc3_calc_trbs_left()
  Revert "USB: serial: ch341: fix character loss at high transfer rates"
  USB: serial: option: add new VID/PID to support Fibocom FG150

Pull powerpc fixes from Michael Ellerman:

 - Fix scv implicit soft-mask table for relocated (eg. kdump) kernels

 - Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK, which was disabled due to a
   typo

Thanks to Lukas Bulwahn, Nicholas Piggin, and Daniel Axtens.

* tag 'powerpc-5.14-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Fix scv implicit soft-mask table for relocated kernels
  powerpc: Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK

Pull block fixes from Jens Axboe:

 - Revert the mq-deadline priority handling, it's causing serious
   performance regressions. While experimental patches exists to fix
   this up, it's too late to do so now. Revert it and re-do it properly
   for 5.15 instead.

 - Fix a NULL vs IS_ERR() regression in this release (Dan)

 - Fix a mq-deadline accounting regression in this release (Bart)

 - Mark cryptoloop as deprecated. It's broken and dm-crypt fully
   supports it, and it's actively intefering with loop. Plan on removal
   for 5.16 (Christoph)

* tag 'block-5.14-2021-08-27' of git://git.kernel.dk/linux-block:
  cryptoloop: add a deprecation warning
  pd: fix a NULL vs IS_ERR() check
  Revert "block/mq-deadline: Prioritize high-priority requests"
  mq-deadline: Fix request accounting

Pull ARM SoC fixes from Arnd Bergmann:
 "Just two trivial fixes from the reset driver tree, nothing else came
  up since the last soc fixes"

* tag 'soc-fixes-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  reset: reset-zynqmp: Fixed the argument data type
  reset: RESET_MCHP_SPARX5 should depend on ARCH_SPARX5

Pull ACPI fix from Rafael Wysocki:
 "Fix a regression introduced during this cycle that has been partially
  addressed by an earlier commit (Andy Shevchenko)"

* tag 'acpi-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  media: ipu3-cio2: Drop reference on error path in cio2_bridge_connect_sensor()

Pull power management fixes from Rafael Wysocki:
 "These fix two issues introduced during this cycle, one of which is a
  regression and the other one affects new code.

  Specifics:

   - Prevent the operating performance points (OPP) code from crashing
     when some entries in the table of required OPPs are set to error
     pointer values (Marijn Suijten)

   - Prevent the generic power domains (genpd) framework from
     incorrectly overriding the performance state of a device set by its
     driver while it is runtime-suspended or when runtime PM of it is
     disabled (Dmitry Osipenko)"

* tag 'pm-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: domains: Improve runtime PM performance state handling
  opp: core: Check for pending links before reading required_opp pointers

virtio_mem_set_fake_offline() might sleep now, and we call it under
rcu_read_lock(). To fix it, simply move the rcu_read_unlock() further
up, as we're done with the device.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 6cc26d77: "virtio-mem: use page_offline_(start|end) when setting PageOffline()
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* pm-opp:
  opp: core: Check for pending links before reading required_opp pointers

Pull RISC-V fixes from Palmer Dabbelt:

 - device tree updates for the Microsemi Polarfire development kit that
   fix some mismatches between the u-boot and Linux enternet entries

 - ensure that the F register state is correctly reflected in core dumps

* tag 'riscv-for-linus-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: dts: microchip: Add ethernet0 to the aliases node
  riscv: dts: microchip: Use 'local-mac-address' for emac1
  riscv: Ensure the value of FP registers in the core dump file is up to date

Pull MMC host fix from Ulf Hansson:

 - sdhci-iproc: Fix clock error for ACPI rpi's

* tag 'mmc-v5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  Revert "mmc: sdhci-iproc: Set SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN on BCM2711"

Support for cryptoloop has been officially marked broken and deprecated
in favor of dm-crypt (which supports the same broken algorithms if
needed) in Linux 2.6.4 (released in March 2004), and support for it has
been entirely removed from losetup in util-linux 2.23 (released in April
2013).  Add a warning and a deprecation schedule.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210827163250.255325-1-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pull ARM fix from Russell King:
 "Resolve a Keystone 2 kernel mapping regression"

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9104/2: Fix Keystone 2 kernel mapping regression

This reverts commit 419dd626.

It turned out that the change from the reverted commit breaks the ACPI
based rpi's because it causes the 100Mhz max clock to be overridden to the
return from sdhci_iproc_get_max_clock(), which is 0 because there isn't a
OF/DT based clock device.
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Fixes: 419dd626 ("mmc: sdhci-iproc: Set SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN on BCM2711")
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

If the endpoint completion callback is call right after the ep_enabled flag
is cleared and before usb_ep_dequeue() is call, we could do a double free
on the request and the associated buffer.

Fix this by clearing ep_enabled after all the endpoint requests have been
dequeued.

Fixes: 7de8681b ("usb: gadget: u_audio: Free requests only after callback")
Cc: stable <stable@vger.kernel.org>
Reported-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210827092927.366482-1-jbrunet@baylibre.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When the uac2 function is stopped, there seems to be an issue reported on
some platforms (Intel Merrifield at least)

BUG: kernel NULL pointer dereference, address: 0000000000000008
...
RIP: 0010:dwc3_gadget_del_and_unmap_request+0x19/0xe0
...
Call Trace:
 dwc3_remove_requests.constprop.0+0x12f/0x170
 __dwc3_gadget_ep_disable+0x7a/0x160
 dwc3_gadget_ep_disable+0x3d/0xd0
 usb_ep_disable+0x1c/0x70
 u_audio_stop_capture+0x79/0x120 [u_audio]
 afunc_set_alt+0x73/0x80 [usb_f_uac2]
 composite_setup+0x224/0x1b90 [libcomposite]

The issue happens only when the gadget is using the sync type "async", not
"adaptive". This indicates that problem is coming from the feedback
endpoint, which is only used with async synchronization mode.

The problem is that request is freed regardless of usb_ep_dequeue(), which
ends up badly if the request is not actually dequeued yet.

Update the feedback endpoint free function to release the endpoint the same
way it is done for the data endpoint, which takes care of the problem.

Fixes: 24f779da ("usb: gadget: f_uac2/u_audio: add feedback endpoint support")
Reported-by: Ferry Toth <ftoth@exalondelft.nl>
Tested-by: Ferry Toth <ftoth@exalondelft.nl>
Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210827075853.266912-1-jbrunet@baylibre.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

blk_mq_alloc_disk() returns error pointers, it doesn't return NULL
so correct the check.

Fixes: 262d431f ("pd: use blk_mq_alloc_disk and blk_cleanup_disk")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210827100023.GB9449@kiliSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pull drm fixes from Dave Airlie:
 "Last set of fixes for 5.14, nothing major a couple of i915, couple of
  imx and a few amdgpu. All pretty small.

  i915:
   - Fix syncmap memory leak
   - Drop redundant display port debug print

  amdgpu:
   - Fix for pinning display buffers multiple times
   - Fix delayed work handling for GFXOFF
   - Fix build when CONFIG_SUSPEND is not set

  imx:
   - fix planar offset calculations
   - fix accidental partial revert"

* tag 'drm-fixes-2021-08-27' of git://anongit.freedesktop.org/drm/drm:
  drm/i915/dp: Drop redundant debug print
  drm/i915: Fix syncmap memory leak
  drm/amdgpu: Fix build with missing pm_suspend_target_state module export
  drm/amdgpu: Cancel delayed work when GFXOFF is disabled
  drm/amdgpu: use the preferred pin domain after the check
  drm/imx: ipuv3-plane: fix accidental partial revert of 8 pixel alignment fix
  gpu: ipu-v3: Fix i.MX IPU-v3 offset calculations for (semi)planar U/V formats

drm/imx: imx-drm alignment and plane offset fixes

Fix an accidental partial revert of commit 94dfec48 ("drm/imx: Add 8
pixel alignment fix") and plane offset calculations for capture of
non-aligned resolutions.
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://patchwork.freedesktop.org/patch/msgid/85a41af99beb2c9e7d6020435a135bf9f205a5ff.camel@pengutronix.de

Merge tag 'amd-drm-fixes-5.14-2021-08-25' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes

amd-drm-fixes-5.14-2021-08-25:

amdgpu:
- Fix for pinning display buffers multiple times
- Fix delayed work handling for GFXOFF
- Fix build when CONFIG_SUSPEND is not set
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210826032658.4068-1-alexander.deucher@amd.com