- Add Gen4 automotive device IDs (Kelvin Cao)

- Declare state_names[] as static so it's not allocated and initialized for
  every call (Kelvin Cao)

* pci/switchtec:
  PCI/switchtec: Declare local state_names[] as static
  PCI/switchtec: Add Gen4 automotive device IDs

- Always write Intel I210 ROM BAR on update to work around device defect
  (Bjorn Helgaas)

* pci/resource:
  PCI: Work around Intel I210 ROM BAR overlap defect

- Add Logan Gunthorpe as P2PDMA maintainer (Bjorn Helgaas)

- Optimize by using percpu_ref_tryget_live_rcu() inside RCU critical
  section (Christophe JAILLET)

* pci/p2pdma:
  PCI/P2PDMA: Use percpu_ref_tryget_live_rcu() inside RCU critical section
  MAINTAINERS: Add Logan Gunthorpe as P2PDMA maintainer

- Convert amd64-agp, sis-agp, via-agp from legacy PCI power management to
  generic power management (Vaibhav Gupta)

* pci/legacy-pm-removal:
  via-agp: convert to generic power management
  sis-agp: convert to generic power management
  amd64-agp: convert to generic power management

- Fix infinite loop in pciehp IRQ handler on power fault (Lukas Wunner)

- Removed commented-out ibmphp functions (Vihas Mak)

- Fix pciehp lockdep errors on Thunderbolt undock (Hans de Goede)

* pci/hotplug:
  PCI: pciehp: Use down_read/write_nested(reset_lock) to fix lockdep errors
  PCI: ibmphp: Remove commented-out functions
  PCI: pciehp: Fix infinite loop in IRQ handler upon power fault

- Use pci_find_vsec_capability() instead of open-coding it (Andy
  Shevchenko)

- Convert pci_dev_present() stub from macro to static inline to avoid
  'unused variable' errors (Hans de Goede)

- Convert sysfs slot attributes from default_attrs to default_groups (Greg
  Kroah-Hartman)

- Use DWORD accesses for LTR, L1 SS to avoid BayHub OZ711LV2 erratum (Rajat
  Jain)

- Remove unnecessary initialization of static variables (Longji Guo)

* pci/enumeration:
  x86/PCI: Remove initialization of static variables to false
  PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum
  PCI/sysfs: Use default_groups in kobj_type for slot attrs
  PCI: Convert pci_dev_present() stub to static inline
  PCI: Use pci_find_vsec_capability() when looking for TBT devices

- Calculate link L0s and L1 exit latencies when needed instead of caching
  them (Saheed O. Bolarinwa)

- Calculate device L0s and L1 acceptable exit latencies when needed instead
  of caching them (Saheed O. Bolarinwa)

- Remove struct aspm_latency since it's no longer needed (Saheed O.
  Bolarinwa)

* pci/aspm:
  PCI/ASPM: Remove struct aspm_latency
  PCI/ASPM: Stop caching device L0s, L1 acceptable exit latencies
  PCI/ASPM: Stop caching link L0s, L1 exit latencies
  PCI/ASPM: Move pci_function_0() upward

Use down_read_nested() and down_write_nested() when taking the
ctrl->reset_lock rw-sem, passing the number of PCIe hotplug controllers in
the path to the PCI root bus as lock subclass parameter.

This fixes the following false-positive lockdep report when unplugging a
Lenovo X1C8 from a Lenovo 2nd gen TB3 dock:

  pcieport 0000:06:01.0: pciehp: Slot(1): Link Down
  pcieport 0000:06:01.0: pciehp: Slot(1): Card not present
  ============================================
  WARNING: possible recursive locking detected
  5.16.0-rc2+ #621 Not tainted
  --------------------------------------------
  irq/124-pciehp/86 is trying to acquire lock:
  ffff8e5ac4299ef8 (&ctrl->reset_lock){.+.+}-{3:3}, at: pciehp_check_presence+0x23/0x80

  but task is already holding lock:
  ffff8e5ac4298af8 (&ctrl->reset_lock){.+.+}-{3:3}, at: pciehp_ist+0xf3/0x180

   other info that might help us debug this:
   Possible unsafe locking scenario:

	 CPU0
	 ----
    lock(&ctrl->reset_lock);
    lock(&ctrl->reset_lock);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  3 locks held by irq/124-pciehp/86:
   #0: ffff8e5ac4298af8 (&ctrl->reset_lock){.+.+}-{3:3}, at: pciehp_ist+0xf3/0x180
   #1: ffffffffa3b024e8 (pci_rescan_remove_lock){+.+.}-{3:3}, at: pciehp_unconfigure_device+0x31/0x110
   #2: ffff8e5ac1ee2248 (&dev->mutex){....}-{3:3}, at: device_release_driver+0x1c/0x40

  stack backtrace:
  CPU: 4 PID: 86 Comm: irq/124-pciehp Not tainted 5.16.0-rc2+ #621
  Hardware name: LENOVO 20U90SIT19/20U90SIT19, BIOS N2WET30W (1.20 ) 08/26/2021
  Call Trace:
   <TASK>
   dump_stack_lvl+0x59/0x73
   __lock_acquire.cold+0xc5/0x2c6
   lock_acquire+0xb5/0x2b0
   down_read+0x3e/0x50
   pciehp_check_presence+0x23/0x80
   pciehp_runtime_resume+0x5c/0xa0
   device_for_each_child+0x45/0x70
   pcie_port_device_runtime_resume+0x20/0x30
   pci_pm_runtime_resume+0xa7/0xc0
   __rpm_callback+0x41/0x110
   rpm_callback+0x59/0x70
   rpm_resume+0x512/0x7b0
   __pm_runtime_resume+0x4a/0x90
   __device_release_driver+0x28/0x240
   device_release_driver+0x26/0x40
   pci_stop_bus_device+0x68/0x90
   pci_stop_bus_device+0x2c/0x90
   pci_stop_and_remove_bus_device+0xe/0x20
   pciehp_unconfigure_device+0x6c/0x110
   pciehp_disable_slot+0x5b/0xe0
   pciehp_handle_presence_or_link_change+0xc3/0x2f0
   pciehp_ist+0x179/0x180

This lockdep warning is triggered because with Thunderbolt, hotplug ports
are nested. When removing multiple devices in a daisy-chain, each hotplug
port's reset_lock may be acquired recursively. It's never the same lock, so
the lockdep splat is a false positive.

Because locks at the same hierarchy level are never acquired recursively, a
per-level lockdep class is sufficient to fix the lockdep warning.

The choice to use one lockdep subclass per pcie-hotplug controller in the
path to the root-bus was made to conserve class keys because their number
is limited and the complexity grows quadratically with number of keys
according to Documentation/locking/lockdep-design.rst.

Link: https://lore.kernel.org/linux-pci/20190402021933.GA2966@mit.edu/
Link: https://lore.kernel.org/linux-pci/de684a28-9038-8fc6-27ca-3f6f2f6400d7@redhat.com/
Link: https://lore.kernel.org/r/20211217141709.379663-1-hdegoede@redhat.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=208855Reported-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org

Remove the initialization of pci_ignore_seg to false which is pointless.

Link: https://lore.kernel.org/r/20211203080758.962-1-guolongji@uniontech.comSigned-off-by: Longji Guo <guolongji@uniontech.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Some devices have an erratum such that they only support DWORD accesses to
some registers.  E.g., this Bayhub O2 device ([VID:DID] = [0x1217:0x8621])
only supports DWORD accesses to LTR latency registers and L1 PM substates
control registers:

  https://github.com/rajatxjain/public_shared/blob/main/OZ711LV2_appnote.pdf

The L1 PM substate control registers are DWORD sized, and hence their
access in the kernel is already DWORD sized, so we don't need to do
anything for them.

However, the LTR registers being WORD sized, are in need of a solution.
Convert the WORD sized accesses to these registers into DWORD sized
accesses while saving and restoring them.

Link: https://lore.kernel.org/r/20211222012105.3438916-1-rajatja@google.comSigned-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Per PCIe r5, sec 7.5.1.2.4, a device must not claim accesses to its
Expansion ROM unless both the Memory Space Enable and the Expansion ROM
Enable bit are set.  But apparently some Intel I210 NICs don't work
correctly if the ROM BAR overlaps another BAR, even if the Expansion ROM is
disabled.

Michael reported that on a Kontron SMARC-sAL28 ARM64 system with U-Boot
v2021.01-rc3, the ROM BAR overlaps BAR 3, and networking doesn't work at
all:

  BAR 0: 0x40000000 (32-bit, non-prefetchable) [size=1M]
  BAR 3: 0x40200000 (32-bit, non-prefetchable) [size=16K]
  ROM:   0x40200000 (disabled) [size=1M]

  NETDEV WATCHDOG: enP2p1s0 (igb): transmit queue 0 timed out
  Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT)
  igb 0002:01:00.0 enP2p1s0: Reset adapter

Previously, pci_std_update_resource() wrote the assigned ROM address to the
BAR only when the ROM was enabled.  This meant that the I210 ROM BAR could
be left with an address assigned by firmware, which might overlap with
other BARs.

Quirk these I210 devices so pci_std_update_resource() always writes the
assigned address to the ROM BAR, whether or not the ROM is enabled.

Link: https://lore.kernel.org/r/20211223163754.GA1267351@bhelgaas
Link: https://lore.kernel.org/r/20201230185317.30915-1-michael@walle.cc
Link: https://bugzilla.kernel.org/show_bug.cgi?id=211105Reported-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

There are currently two ways to create a set of sysfs files for a
kobj_type: through the default_attrs field, and the default_groups field.
Move the PCI slot code to use the default_groups field which has been the
preferred way since aa30f47c ("kobject: Add support for default
attribute groups to kobj_type") so that we can soon get rid of the obsolete
default_attrs field.

Link: https://lore.kernel.org/r/20211228135722.381023-1-gregkh@linuxfoundation.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Change the pci_dev_present() stub which is used when CONFIG_PCI is not set
from a #define to a static inline stub.

Thix should fix clang -Werror builds failing due to errors like this:

  drivers/platform/x86/thinkpad_acpi.c:4475:35:
   error: unused variable 'fwbug_cards_ids' [-Werror,-Wunused-const-variable]

Where fwbug_cards_ids is an array of pci_device_id passed to
pci_dev_present() during a quirk check.

Link: https://lore.kernel.org/r/20211217141515.379586-1-hdegoede@redhat.comReported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: platform-driver-x86@vger.kernel.org

Since pci_alloc_p2pmem() has already called rcu_read_lock(), we're in an
RCU read-side critical section and don't need to take the lock again.  Use
percpu_ref_tryget_live_rcu() instead of percpu_ref_tryget_live() to save a
few cycles.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/ab80164f4d5b32f9e6240aa4863c3a147ff9c89f.1635974126.git.christophe.jaillet@wanadoo.frSigned-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

Add a P2PDMA entry to make sure Logan is aware of changes to that area.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com>

Convert via-agp from legacy PCI power management to the generic power
management framework.

Previously, via-agp used legacy PCI power management, and agp_via_suspend()
and agp_via_resume() were responsible for both device-specific things and
generic PCI things:

  agp_via_suspend
    pci_save_state(pdev)                <-- generic PCI
    pci_set_power_state(pdev, pci_choose_state(pdev, state)) <-- generic PCI

  agp_via_resume
    pci_set_power_state(pdev, PCI_D0)   <-- generic PCI
    pci_restore_state(pdev)             <-- generic PCI
    via_configure_agp3()                <-- device-specific
    via_configure()                     <-- device-specific

With generic power management, the PCI bus PM methods do the generic PCI
things, and the driver needs only the device-specific part, i.e.,

  suspend_devices_and_enter
    dpm_suspend_start(PMSG_SUSPEND)
      pci_pm_suspend                    # PCI bus .suspend() method
        agp_via_suspend                 <-- not needed at all; removed
    suspend_enter
      dpm_suspend_noirq(PMSG_SUSPEND)
        pci_pm_suspend_noirq            # PCI bus .suspend_noirq() method
          pci_save_state                <-- generic PCI
          pci_prepare_to_sleep          <-- generic PCI
            pci_set_power_state
    ...
    dpm_resume_end(PMSG_RESUME)
      pci_pm_resume                     # PCI bus .resume() method
        pci_restore_standard_config
          pci_set_power_state(PCI_D0)   <-- generic PCI
          pci_restore_state             <-- generic PCI
        agp_via_resume                  # dev->driver->pm->resume
          via_configure_agp3()          <-- device-specific
          via_configure()               <-- device-specific

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20211208193305.147072-4-helgaas@kernel.orgSigned-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>

Convert sis-agp from legacy PCI power management to the generic power
management framework.

Previously, sis-agp used legacy PCI power management, and agp_sis_suspend()
and agp_sis_resume() were responsible for both device-specific things and
generic PCI things:

  agp_sis_suspend
    pci_save_state(pdev)                <-- generic PCI
    pci_set_power_state(pdev, pci_choose_state(pdev, state)) <-- generic PCI

  agp_sis_resume
    pci_set_power_state(pdev, PCI_D0)   <-- generic PCI
    pci_restore_state(pdev)             <-- generic PCI
    sis_driver.configure()              <-- device-specific

With generic power management, the PCI bus PM methods do the generic PCI
things, and the driver needs only the device-specific part, i.e.,

  suspend_devices_and_enter
    dpm_suspend_start(PMSG_SUSPEND)
      pci_pm_suspend                    # PCI bus .suspend() method
        agp_sis_suspend                 <-- not needed at all; removed
    suspend_enter
      dpm_suspend_noirq(PMSG_SUSPEND)
        pci_pm_suspend_noirq            # PCI bus .suspend_noirq() method
          pci_save_state                <-- generic PCI
          pci_prepare_to_sleep          <-- generic PCI
            pci_set_power_state
    ...
    dpm_resume_end(PMSG_RESUME)
      pci_pm_resume                     # PCI bus .resume() method
        pci_restore_standard_config
          pci_set_power_state(PCI_D0)   <-- generic PCI
          pci_restore_state             <-- generic PCI
        agp_sis_resume                  # dev->driver->pm->resume
          sis_driver.configure()        <-- device-specific

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20211208193305.147072-3-helgaas@kernel.orgSigned-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>

Convert amd64-agp from legacy PCI power management to the generic power
management framework.

Previously, amd64-agp used legacy PCI power management, and
agp_amd64_suspend() and agp_amd64_resume() were responsible for both
device-specific things and generic PCI things:

  agp_amd64_suspend
    pci_save_state(pdev)                <-- generic PCI
    pci_set_power_state(pdev, pci_choose_state(pdev, state)) <-- generic PCI

  agp_amd64_resume
    pci_set_power_state(pdev, PCI_D0)   <-- generic PCI
    pci_restore_state(pdev)             <-- generic PCI
    nforce3_agp_init()                  <-- device-specific
    amd_8151_configure()                <-- device-specific

With generic power management, the PCI bus PM methods do the generic PCI
things, and the driver needs only the device-specific part, i.e.,

  suspend_devices_and_enter
    dpm_suspend_start(PMSG_SUSPEND)
      pci_pm_suspend                    # PCI bus .suspend() method
        agp_amd64_suspend               <-- not needed at all; removed
    suspend_enter
      dpm_suspend_noirq(PMSG_SUSPEND)
        pci_pm_suspend_noirq            # PCI bus .suspend_noirq() method
          pci_save_state                <-- generic PCI
          pci_prepare_to_sleep          <-- generic PCI
            pci_set_power_state
    ...
    dpm_resume_end(PMSG_RESUME)
      pci_pm_resume                     # PCI bus .resume() method
        pci_restore_standard_config
          pci_set_power_state(PCI_D0)   <-- generic PCI
          pci_restore_state             <-- generic PCI
        agp_amd64_resume                # dev->driver->pm->resume
          nforce3_agp_init()            <-- device-specific
          amd_8151_configure()          <-- device-specific

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20211208193305.147072-2-helgaas@kernel.orgSigned-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>

The functions get_max_adapter_speed() and get_bus_name() in ibmphp_core.c
are commented-out and the fields .get_max_adapter_speed and
.get_bus_name_status are removed from struct hotplug_slot_ops in
pci_hotplug.h. Remove the commented-out functions.

Link: https://lore.kernel.org/r/20211209213618.20522-1-makvihas@gmail.comSigned-off-by: Vihas Mak <makvihas@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

The struct aspm_latency is now used only inside pcie_aspm_check_latency().

Replace struct aspm_latency variables with u32 variables and remove struct
aspm_latency.

Link: https://lore.kernel.org/r/20211119193732.12343-5-refactormyself@gmail.comSigned-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Previously we calculated the device's acceptable L0s and L1 exit latencies
in pcie_aspm_cap_init() and cached them in struct pcie_link_state.

These values are only used in pcie_aspm_check_latency() where they are
compared with the actual exit latencies of the link.  This path is used
when removing or changing the D state of the device, so it's relatively low
frequency.

To reduce the amount of per-link data we store, remove the acceptable[]
arrays from struct pcie_link_state and calculate them directly from the
already-cached Device Capabilities register when needed.

[bhelgaas: use endpoint->devcap instead of reading it again]
Link: https://lore.kernel.org/r/20211119193732.12343-4-refactormyself@gmail.comSigned-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Previously we calculated the upstream and downstream L0s and L1 exit
latencies of the link in pcie_aspm_cap_init() and cached them in struct
pcie_link_state.latency_*.

These values are only used in pcie_aspm_check_latency() where they are
compared with the acceptable latencies on the link.  This path is used when
removing or changing the D state of the device, so it's relatively low
frequency.

To reduce the amount of per-link data we store, remove the latency_*
entries from struct pcie_link_state and calculate the latencies directly
where they are needed.

Link: https://lore.kernel.org/r/20211119193732.12343-3-refactormyself@gmail.comSigned-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Move pci_function_0() earlier so we can use it from other functions.

Link: https://lore.kernel.org/r/20211119193732.12343-2-refactormyself@gmail.comSigned-off-by: Bolarinwa O. Saheed <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

The Power Fault Detected bit in the Slot Status register differs from
all other hotplug events in that it is sticky:  It can only be cleared
after turning off slot power.  Per PCIe r5.0, sec. 6.7.1.8:

  If a power controller detects a main power fault on the hot-plug slot,
  it must automatically set its internal main power fault latch [...].
  The main power fault latch is cleared when software turns off power to
  the hot-plug slot.

The stickiness used to cause interrupt storms and infinite loops which
were fixed in 2009 by commits 5651c48c ("PCI pciehp: fix power fault
interrupt storm problem") and 99f0169c ("PCI: pciehp: enable
software notification on empty slots").

Unfortunately in 2020 the infinite loop issue was inadvertently
reintroduced by commit 8edf5332 ("PCI: pciehp: Fix MSI interrupt
race"):  The hardirq handler pciehp_isr() clears the PFD bit until
pciehp's power_fault_detected flag is set.  That happens in the IRQ
thread pciehp_ist(), which never learns of the event because the hardirq
handler is stuck in an infinite loop.  Fix by setting the
power_fault_detected flag already in the hardirq handler.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214989
Link: https://lore.kernel.org/linux-pci/DM8PR11MB5702255A6A92F735D90A4446868B9@DM8PR11MB5702.namprd11.prod.outlook.com
Fixes: 8edf5332 ("PCI: pciehp: Fix MSI interrupt race")
Link: https://lore.kernel.org/r/66eaeef31d4997ceea357ad93259f290ededecfd.1637187226.git.lukas@wunner.deReported-by: Joseph Bao <joseph.bao@intel.com>
Tested-by: Joseph Bao <joseph.bao@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v4.19+
Cc: Stuart Hayes <stuart.w.hayes@gmail.com>

The local state_names[] array is constant and need not be allocated and
populated each time we enter stuser_set_state().  Declare it as static.

See the link below for the discussion.

  https://lore.kernel.org/r/20211014141859.11444-1-kelvin.cao@microchip.com/

[bhelgaas: simplify commit log]
Suggested-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20211119003803.2333-3-kelvin.cao@microchip.comSigned-off-by: Kelvin Cao <kelvin.cao@microchip.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

Advertise support of the Gen4 automotive variants in module's device ID
table and add the same IDs to the list of switchtec quirks.

Link: https://lore.kernel.org/r/20211119003803.2333-2-kelvin.cao@microchip.comSigned-off-by: Kelvin Cao <kelvin.cao@microchip.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

Currently set_pcie_thunderbolt() open-codes pci_find_vsec_capability().
Refactor the former to use the latter. No functional change intended.

Link: https://lore.kernel.org/r/20211115112902.24033-1-andriy.shevchenko@linux.intel.comSigned-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>

Add Kconfig support for -Wimplicit-fallthrough for both GCC and Clang.

The compiler option is under configuration CC_IMPLICIT_FALLTHROUGH,
which is enabled by default.

Special thanks to Nathan Chancellor who fixed the Clang bug[1][2]. This
bugfix only appears in Clang 14.0.0, so older versions still contain
the bug and -Wimplicit-fallthrough won't be enabled for them, for now.

This concludes a long journey and now we are finally getting rid
of the unintentional fallthrough bug-class in the kernel, entirely. :)

Link: https://github.com/llvm/llvm-project/commit/9ed4a94d6451046a51ef393cd62f00710820a7e8 [1]
Link: https://bugs.llvm.org/show_bug.cgi?id=51094 [2]
Link: https://github.com/KSPP/linux/issues/115
Link: https://github.com/ClangBuiltLinux/linux/issues/236Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull xfs cleanups from Darrick Wong:
 "The most 'exciting' aspect of this branch is that the xfsprogs
  maintainer and I have worked through the last of the code
  discrepancies between kernel and userspace libxfs such that there are
  no code differences between the two except for #includes.

  IOWs, diff suffices to demonstrate that the userspace tools behave the
  same as the kernel, and kernel-only bits are clearly marked in the
  /kernel/ source code instead of just the userspace source.

  Summary:

   - Clean up open-coded swap() calls.

   - A little bit of #ifdef golf to complete the reunification of the
     kernel and userspace libxfs source code"

* tag 'xfs-5.16-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: sync xfs_btree_split macros with userspace libxfs
  xfs: #ifdef out perag code for userspace
  xfs: use swap() to make dabtree code cleaner

Pull more parisc fixes from Helge Deller:
 "Fix a build error in stracktrace.c, fix resolving of addresses to
  function names in backtraces, fix single-stepping in assembly code and
  flush userspace pte's when using set_pte_at()"

* tag 'for-5.16/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc/entry: fix trace test in syscall exit path
  parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page
  parisc: Fix implicit declaration of function '__kernel_text_address'
  parisc: Fix backtrace to always include init funtion names

Pull arch/sh updates from Rich Felker.

* tag 'sh-for-5.16' of git://git.libc.org/linux-sh:
  sh: pgtable-3level: Fix cast to pointer from integer of different size
  sh: fix READ/WRITE redefinition warnings
  sh: define __BIG_ENDIAN for math-emu
  sh: math-emu: drop unused functions
  sh: fix kconfig unmet dependency warning for FRAME_POINTER
  sh: Cleanup about SPARSE_IRQ
  sh: kdump: add some attribute to function
  maple: fix wrong return value of maple_bus_init().
  sh: boot: avoid unneeded rebuilds under arch/sh/boot/compressed/
  sh: boot: add intermediate vmlinux.bin* to targets instead of extra-y
  sh: boards: Fix the cacography in irq.c
  sh: check return code of request_irq
  sh: fix trivial misannotations

Pull ARM fixes from Russell King:

 - Fix early_iounmap

 - Drop cc-option fallbacks for architecture selection

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9156/1: drop cc-option fallbacks for architecture selection
  ARM: 9155/1: fix early early_iounmap()

Pull devicetree fixes from Rob Herring:

 - Two fixes due to DT node name changes on Arm, Ltd. boards

 - Treewide rename of Ingenic CGU headers

 - Update ST email addresses

 - Remove Netlogic DT bindings

 - Dropping few more cases of redundant 'maxItems' in schemas

 - Convert toshiba,tc358767 bridge binding to schema

* tag 'devicetree-fixes-for-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: watchdog: sunxi: fix error in schema
  bindings: media: venus: Drop redundant maxItems for power-domain-names
  dt-bindings: Remove Netlogic bindings
  clk: versatile: clk-icst: Ensure clock names are unique
  of: Support using 'mask' in making device bus id
  dt-bindings: treewide: Update @st.com email address to @foss.st.com
  dt-bindings: media: Update maintainers for st,stm32-hwspinlock.yaml
  dt-bindings: media: Update maintainers for st,stm32-cec.yaml
  dt-bindings: mfd: timers: Update maintainers for st,stm32-timers
  dt-bindings: timer: Update maintainers for st,stm32-timer
  dt-bindings: i2c: imx: hardware do not restrict clock-frequency to only 100 and 400 kHz
  dt-bindings: display: bridge: Convert toshiba,tc358767.txt to yaml
  dt-bindings: Rename Ingenic CGU headers to ingenic,*.h

Pull timer fix from Thomas Gleixner:
 "A single fix for POSIX CPU timers to address a problem where POSIX CPU
  timer delivery stops working for a new child task because
  copy_process() copies state information which is only valid for the
  parent task"

* tag 'timers-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()

Pull irq fixes from Thomas Gleixner:
 "A set of fixes for the interrupt subsystem

  Core code:

   - A regression fix for the Open Firmware interrupt mapping code where
     a interrupt controller property in a node caused a map property in
     the same node to be ignored.

  Interrupt chip drivers:

   - Workaround a limitation in SiFive PLIC interrupt chip which
     silently ignores an EOI when the interrupt line is masked.

   - Provide the missing mask/unmask implementation for the CSKY MP
     interrupt controller.

  PCI/MSI:

   - Prevent a use after free when PCI/MSI interrupts are released by
     destroying the sysfs entries before freeing the memory which is
     accessed in the sysfs show() function.

   - Implement a mask quirk for the Nvidia ION AHCI chip which does not
     advertise masking capability despite implementing it. Even worse
     the chip comes out of reset with all MSI entries masked, which due
     to the missing masking capability never get unmasked.

   - Move the check which prevents accessing the MSI[X] masking for XEN
     back into the low level accessors. The recent consolidation missed
     that these accessors can be invoked from places which do not have
     that check which broke XEN. Move them back to he original place
     instead of sprinkling tons of these checks all over the code"

* tag 'irq-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  of/irq: Don't ignore interrupt-controller when interrupt-map failed
  irqchip/sifive-plic: Fixup EOI failed when masked
  irqchip/csky-mpintc: Fixup mask/unmask implementation
  PCI/MSI: Destroy sysfs before freeing entries
  PCI: Add MSI masking quirk for Nvidia ION AHCI
  PCI/MSI: Deal with devices lying about their MSI mask capability
  PCI/MSI: Move non-mask check back into low level accessors

Pull x86 static call update from Thomas Gleixner:
 "A single fix for static calls to make the trampoline patching more
  robust by placing explicit signature bytes after the call trampoline
  to prevent patching random other jumps like the CFI jump table
  entries"

* tag 'locking-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  static_call,x86: Robustify trampoline patching

Pull scheduler fixes from Borislav Petkov:

 - Avoid touching ~100 config files in order to be able to select the
   preemption model

 - clear cluster CPU masks too, on the CPU unplug path

 - prevent use-after-free in cfs

 - Prevent a race condition when updating CPU cache domains

 - Factor out common shared part of smp_prepare_cpus() into a common
   helper which can be called by both baremetal and Xen, in order to fix
   a booting of Xen PV guests

* tag 'sched_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  preempt: Restore preemption model selection configs
  arch_topology: Fix missing clear cluster_cpumask in remove_cpu_topology()
  sched/fair: Prevent dead task groups from regaining cfs_rq's
  sched/core: Mitigate race cpus_share_cache()/update_top_cache_domain()
  x86/smp: Factor out parts of native_smp_prepare_cpus()

Pull perf fixes from Borislav Petkov:

 - Prevent unintentional page sharing by checking whether a page
   reference to a PMU samples page has been acquired properly before
   that

 - Make sure the LBR_SELECT MSR is saved/restored too

 - Reset the LBR_SELECT MSR when resetting the LBR PMU to clear any
   residual data left

* tag 'perf_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Avoid put_page() when GUP fails
  perf/x86/vlbr: Add c->flags to vlbr event constraints
  perf/x86/lbr: Reset LBR_SELECT during vlbr reset

Pull x86 fixes from Borislav Petkov:

 - Add the model number of a new, Raptor Lake CPU, to intel-family.h

 - Do not log spurious corrected MCEs on SKL too, due to an erratum

 - Clarify the path of paravirt ops patches upstream

 - Add an optimization to avoid writing out AMX components to sigframes
   when former are in init state

* tag 'x86_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Add Raptor Lake to Intel family
  x86/mce: Add errata workaround for Skylake SKX37
  MAINTAINERS: Add some information to PARAVIRT_OPS entry
  x86/fpu: Optimize out sigframe xfeatures when in init state