Commit Graph

1329 Commits

Author SHA1 Message Date
Ilpo Järvinen
f647b8fe55 PCI: pciehp: Use RMW accessors for changing LNKCTL
[ Upstream commit 5f75f96c61039151c193775d776fde42477eace1 ]

As hotplug is not the only driver touching LNKCTL, use the RMW capability
accessor which handles concurrent changes correctly.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Fixes: 7f822999e1 ("PCI: pciehp: Add Disable/enable link functions")
Link: https://lore.kernel.org/r/20230717120503.15276-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-19 12:20:14 +02:00
Igor Mammedov
ff0639b222 PCI: acpiphp: Use pci_assign_unassigned_bridge_resources() only for non-root bus
commit cc22522fd55e257c86d340ae9aedc122e705a435 upstream.

40613da52b13 ("PCI: acpiphp: Reassign resources on bridge if necessary")
changed acpiphp hotplug to use pci_assign_unassigned_bridge_resources()
which depends on bridge being available, however enable_slot() can be
called without bridge associated:

  1. Legitimate case of hotplug on root bus (widely used in virt world)

  2. A (misbehaving) firmware, that sends ACPI Bus Check notifications to
     non existing root ports (Dell Inspiron 7352/0W6WV0), which end up at
     enable_slot(..., bridge = 0) where bus has no bridge assigned to it.
     acpihp doesn't know that it's a bridge, and bus specific 'PCI
     subsystem' can't augment ACPI context with bridge information since
     the PCI device to get this data from is/was not available.

Issue is easy to reproduce with QEMU's 'pc' machine, which supports PCI
hotplug on hostbridge slots. To reproduce, boot kernel at commit
40613da52b13 in VM started with following CLI (assuming guest root fs is
installed on sda1 partition):

  # qemu-system-x86_64 -M pc -m 1G -enable-kvm -cpu host \
        -monitor stdio -serial file:serial.log           \
        -kernel arch/x86/boot/bzImage                    \
        -append "root=/dev/sda1 console=ttyS0"           \
        guest_disk.img

Once guest OS is fully booted at qemu prompt:

  (qemu) device_add e1000

(check serial.log) it will cause NULL pointer dereference at:

  void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
  {
    struct pci_bus *parent = bridge->subordinate;

  BUG: kernel NULL pointer dereference, address: 0000000000000018

   ? pci_assign_unassigned_bridge_resources+0x1f/0x260
   enable_slot+0x21f/0x3e0
   acpiphp_hotplug_notify+0x13d/0x260
   acpi_device_hotplug+0xbc/0x540
   acpi_hotplug_work_fn+0x15/0x20
   process_one_work+0x1f7/0x370
   worker_thread+0x45/0x3b0

The issue was discovered on Dell Inspiron 7352/0W6WV0 laptop with following
sequence:

  1. Suspend to RAM
  2. Wake up with the same backtrace being observed:
  3. 2nd suspend to RAM attempt makes laptop freeze

Fix it by using __pci_bus_assign_resources() instead of
pci_assign_unassigned_bridge_resources() as we used to do, but only in case
when bus doesn't have a bridge associated (to cover for the case of ACPI
event on hostbridge or non existing root port).

That lets us keep hotplug on root bus working like it used to and at the
same time keeps resource reassignment usable on root ports (and other 1st
level bridges) that was fixed by 40613da52b13.

Fixes: 40613da52b13 ("PCI: acpiphp: Reassign resources on bridge if necessary")
Link: https://lore.kernel.org/r/20230726123518.2361181-2-imammedo@redhat.com
Reported-by: Woody Suwalski <terraluna977@gmail.com>
Tested-by: Woody Suwalski <terraluna977@gmail.com>
Tested-by: Michal Koutný <mkoutny@suse.com>
Link: https://lore.kernel.org/r/11fc981c-af49-ce64-6b43-3e282728bd1a@gmail.com
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-30 16:23:16 +02:00
Igor Mammedov
cd689b5912 PCI: acpiphp: Reassign resources on bridge if necessary
[ Upstream commit 40613da52b13fb21c5566f10b287e0ca8c12c4e9 ]

When using ACPI PCI hotplug, hotplugging a device with large BARs may fail
if bridge windows programmed by firmware are not large enough.

Reproducer:
  $ qemu-kvm -monitor stdio -M q35  -m 4G \
      -global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=on \
      -device id=rp1,pcie-root-port,bus=pcie.0,chassis=4 \
      disk_image

 wait till linux guest boots, then hotplug device:
   (qemu) device_add qxl,bus=rp1

 hotplug on guest side fails with:
   pci 0000:01:00.0: [1b36:0100] type 00 class 0x038000
   pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x03ffffff]
   pci 0000:01:00.0: reg 0x14: [mem 0x00000000-0x03ffffff]
   pci 0000:01:00.0: reg 0x18: [mem 0x00000000-0x00001fff]
   pci 0000:01:00.0: reg 0x1c: [io  0x0000-0x001f]
   pci 0000:01:00.0: BAR 0: no space for [mem size 0x04000000]
   pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x04000000]
   pci 0000:01:00.0: BAR 1: no space for [mem size 0x04000000]
   pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x04000000]
   pci 0000:01:00.0: BAR 2: assigned [mem 0xfe800000-0xfe801fff]
   pci 0000:01:00.0: BAR 3: assigned [io  0x1000-0x101f]
   qxl 0000:01:00.0: enabling device (0000 -> 0003)
   Unable to create vram_mapping
   qxl: probe of 0000:01:00.0 failed with error -12

However when using native PCIe hotplug
  '-global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=off'
it works fine, since kernel attempts to reassign unused resources.

Use the same machinery as native PCIe hotplug to (re)assign resources.

Link: https://lore.kernel.org/r/20230424191557.2464760-1-imammedo@redhat.com
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-30 16:23:09 +02:00
Rongguang Wei
cb389e8edf PCI: pciehp: Cancel bringup sequence if card is not present
[ Upstream commit e8afd0d9fccc27c8ad263db5cf5952cfcf72d6fe ]

If a PCIe hotplug slot has an Attention Button, the normal hot-add flow is:

  - Slot is empty and slot power is off
  - User inserts card in slot and presses Attention Button
  - OS blinks Power Indicator for 5 seconds
  - After 5 seconds, OS turns on Power Indicator, turns on slot power, and
    enumerates the device

Previously, if a user pressed the Attention Button on an *empty* slot,
pciehp logged the following messages and blinked the Power Indicator
until a second button press:

  [0.000] pciehp: Button press: will power on in 5 sec
  [0.001] # Power Indicator starts blinking
  [5.001] # 5 second timeout; slot is empty, so we should cancel the
            request to power on and turn off Power Indicator

  [7.000] # Power Indicator still blinking
  [8.000] # possible card insertion
  [9.000] pciehp: Button press: canceling request to power on

The first button press incorrectly left the slot in BLINKINGON_STATE, so
the second was interpreted as a "cancel power on" event regardless of
whether a card was present.

If the slot is empty, turn off the Power Indicator and return from
BLINKINGON_STATE to OFF_STATE after 5 seconds, effectively canceling the
request to power on.  Putting the slot in OFF_STATE also means the second
button press will correctly request a slot power on if the slot is
occupied.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20230512021518.336460-1-clementwei90@163.com
Fixes: d331710ea7 ("PCI: pciehp: Become resilient to missed events")
Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rongguang Wei <weirongguang@kylinos.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:43:56 +02:00
Lukas Wunner
2f31633da8 PCI: pciehp: Fix AB-BA deadlock between reset_lock and device_lock
commit f5eff5591b8f9c5effd25c92c758a127765f74c1 upstream.

In 2013, commits

  2e35afaefe ("PCI: pciehp: Add reset_slot() method")
  608c388122 ("PCI: Add slot reset option to pci_dev_reset()")

amended PCIe hotplug to mask Presence Detect Changed events during a
Secondary Bus Reset.  The reset thus no longer causes gratuitous slot
bringdown and bringup.

However the commits neglected to serialize reset with code paths reading
slot registers.  For instance, a slot bringup due to an earlier hotplug
event may see the Presence Detect State bit cleared during a concurrent
Secondary Bus Reset.

In 2018, commit

  5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")

retrofitted the missing locking.  It introduced a reset_lock which
serializes a Secondary Bus Reset with other parts of pciehp.

Unfortunately the locking turns out to be overzealous:  reset_lock is
held for the entire enumeration and de-enumeration of hotplugged devices,
including driver binding and unbinding.

Driver binding and unbinding acquires device_lock while the reset_lock
of the ancestral hotplug port is held.  A concurrent Secondary Bus Reset
acquires the ancestral reset_lock while already holding the device_lock.
The asymmetric locking order in the two code paths can lead to AB-BA
deadlocks.

Michael Haeuptle reports such deadlocks on simultaneous hot-removal and
vfio release (the latter implies a Secondary Bus Reset):

  pciehp_ist()                                    # down_read(reset_lock)
    pciehp_handle_presence_or_link_change()
      pciehp_disable_slot()
        __pciehp_disable_slot()
          remove_board()
            pciehp_unconfigure_device()
              pci_stop_and_remove_bus_device()
                pci_stop_bus_device()
                  pci_stop_dev()
                    device_release_driver()
                      device_release_driver_internal()
                        __device_driver_lock()    # device_lock()

  SYS_munmap()
    vfio_device_fops_release()
      vfio_device_group_close()
        vfio_device_close()
          vfio_device_last_close()
            vfio_pci_core_close_device()
              vfio_pci_core_disable()             # device_lock()
                __pci_reset_function_locked()
                  pci_reset_bus_function()
                    pci_dev_reset_slot_function()
                      pci_reset_hotplug_slot()
                        pciehp_reset_slot()       # down_write(reset_lock)

Ian May reports the same deadlock on simultaneous hot-removal and an
AER-induced Secondary Bus Reset:

  aer_recover_work_func()
    pcie_do_recovery()
      aer_root_reset()
        pci_bus_error_reset()
          pci_slot_reset()
            pci_slot_lock()                       # device_lock()
            pci_reset_hotplug_slot()
              pciehp_reset_slot()                 # down_write(reset_lock)

Fix by releasing the reset_lock during driver binding and unbinding,
thereby splitting and shrinking the critical section.

Driver binding and unbinding is protected by the device_lock() and thus
serialized with a Secondary Bus Reset.  There's no need to additionally
protect it with the reset_lock.  However, pciehp does not bind and
unbind devices directly, but rather invokes PCI core functions which
also perform certain enumeration and de-enumeration steps.

The reset_lock's purpose is to protect slot registers, not enumeration
and de-enumeration of hotplugged devices.  That would arguably be the
job of the PCI core, not the PCIe hotplug driver.  After all, an
AER-induced Secondary Bus Reset may as well happen during boot-time
enumeration of the PCI hierarchy and there's no locking to prevent that
either.

Exempting *de-enumeration* from the reset_lock is relatively harmless:
A concurrent Secondary Bus Reset may foil config space accesses such as
PME interrupt disablement.  But if the device is physically gone, those
accesses are pointless anyway.  If the device is physically present and
only logically removed through an Attention Button press or the sysfs
"power" attribute, PME interrupts as well as DMA cannot come through
because pciehp_unconfigure_device() disables INTx and Bus Master bits.
That's still protected by the reset_lock in the present commit.

Exempting *enumeration* from the reset_lock also has limited impact:
The exempted call to pci_bus_add_device() may perform device accesses
through pcibios_bus_add_device() and pci_fixup_device() which are now
no longer protected from a concurrent Secondary Bus Reset.  Otherwise
there should be no impact.

In essence, the present commit seeks to fix the AB-BA deadlocks while
still retaining a best-effort reset protection for enumeration and
de-enumeration of hotplugged devices -- until a general solution is
implemented in the PCI core.

Link: https://lore.kernel.org/linux-pci/CS1PR8401MB0728FC6FDAB8A35C22BD90EC95F10@CS1PR8401MB0728.NAMPRD84.PROD.OUTLOOK.COM
Link: https://lore.kernel.org/linux-pci/20200615143250.438252-1-ian.may@canonical.com
Link: https://lore.kernel.org/linux-pci/ce878dab-c0c4-5bd0-a725-9805a075682d@amd.com
Link: https://lore.kernel.org/linux-pci/ed831249-384a-6d35-0831-70af191e9bce@huawei.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215590
Fixes: 5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")
Link: https://lore.kernel.org/r/fef2b2e9edf245c049a8c5b94743c0f74ff5008a.1681191902.git.lukas@wunner.de
Reported-by: Michael Haeuptle <michael.haeuptle@hpe.com>
Reported-by: Ian May <ian.may@canonical.com>
Reported-by: Andrey Grodzovsky <andrey2805@gmail.com>
Reported-by: Rahul Kumar <rahul.kumar1@amd.com>
Reported-by: Jialin Zhang <zhangjialin11@huawei.com>
Tested-by: Anatoli Antonovitch <Anatoli.Antonovitch@amd.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: Dan Stein <dstein@hpe.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Alex Michon <amichon@kalrayinc.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:47:31 +02:00
Manivannan Sadhasivam
c66cc04043 PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
[ Upstream commit 9f72d4757cbe4d1ed669192f6d23817c9e437c4b ]

The Qualcomm PCI bridge device (Device ID 0x0110) found in chipsets such as
SM8450 does not set the Command Completed bit unless writes to the Slot
Command register change "Control" bits.

This results in timeouts like below:

  pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2020 msec ago)

Add the device to the Command Completed quirk to mark commands "completed"
immediately unless they change the "Control" bits.

Link: https://lore.kernel.org/r/20220210145003.135907-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:00:57 +02:00
Liguang Zhang
0f56f24015 PCI: pciehp: Clear cmd_busy bit in polling mode
commit 92912b175178c7e895f5e5e9f1e30ac30319162b upstream.

Writes to a Downstream Port's Slot Control register are PCIe hotplug
"commands."  If the Port supports Command Completed events, software must
wait for a command to complete before writing to Slot Control again.

pcie_do_write_cmd() sets ctrl->cmd_busy when it writes to Slot Control.  If
software notification is enabled, i.e., PCI_EXP_SLTCTL_HPIE and
PCI_EXP_SLTCTL_CCIE are set, ctrl->cmd_busy is cleared by pciehp_isr().

But when software notification is disabled, as it is when pcie_init()
powers off an empty slot, pcie_wait_cmd() uses pcie_poll_cmd() to poll for
command completion, and it neglects to clear ctrl->cmd_busy, which leads to
spurious timeouts:

  pcieport 0000:00:03.0: pciehp: Timeout on hotplug command 0x01c0 (issued 2264 msec ago)
  pcieport 0000:00:03.0: pciehp: Timeout on hotplug command 0x05c0 (issued 2288 msec ago)

Clear ctrl->cmd_busy in pcie_poll_cmd() when it detects a Command Completed
event (PCI_EXP_SLTSTA_CC).

[bhelgaas: commit log]
Fixes: a5dd4b4b05 ("PCI: pciehp: Wait for hotplug command completion where necessary")
Link: https://lore.kernel.org/r/20211111054258.7309-1-zhangliguang@linux.alibaba.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215143
Link: https://lore.kernel.org/r/20211126173309.GA12255@wunner.de
Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org	# v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:39:58 +02:00
Lukas Wunner
3b4c966fb1 PCI: pciehp: Fix infinite loop in IRQ handler upon power fault
commit 23584c1ed3e15a6f4bfab8dc5a88d94ab929ee12 upstream.

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 5651c48cfa ("PCI pciehp: fix power fault
interrupt storm problem") and 99f0169c17 ("PCI: pciehp: enable
software notification on empty slots").

Unfortunately in 2020 the infinite loop issue was inadvertently
reintroduced by commit 8edf5332c3 ("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: 8edf5332c3 ("PCI: pciehp: Fix MSI interrupt race")
Link: https://lore.kernel.org/r/66eaeef31d4997ceea357ad93259f290ededecfd.1637187226.git.lukas@wunner.de
Reported-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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-05 12:37:54 +01:00
Hans de Goede
def2825b09 PCI: pciehp: Use down_read/write_nested(reset_lock) to fix lockdep errors
commit 085a9f43433f30cbe8a1ade62d9d7827c3217f4d upstream.

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=208855
Reported-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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 10:54:26 +01:00
Niklas Schnelle
188907c252 s390/pci: fix zpci_zdev_put() on reserve
commit a46044a92add6a400f4dada7b943b30221f7cc80 upstream.

Since commit 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev")
the reference count of a zpci_dev is incremented between
pcibios_add_device() and pcibios_release_device() which was supposed to
prevent the zpci_dev from being freed while the common PCI code has
access to it. It was missed however that the handling of zPCI
availability events assumed that once zpci_zdev_put() was called no
later availability event would still see the device. With the previously
mentioned commit however this assumption no longer holds and we must
make sure that we only drop the initial long-lived reference the zPCI
subsystem holds exactly once.

Do so by introducing a zpci_device_reserved() function that handles when
a device is reserved. Here we make sure the zpci_dev will not be
considered for further events by removing it from the zpci_list.

This also means that the device actually stays in the
ZPCI_FN_STATE_RESERVED state between the time we know it has been
reserved and the final reference going away. We thus need to consider it
a real state instead of just a conceptual state after the removal. The
final cleanup of PCI resources, removal from zbus, and destruction of
the IOMMU stays in zpci_release_device() to make sure holders of the
reference do see valid data until the release.

Fixes: 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev")
Cc: stable@vger.kernel.org
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-27 09:56:56 +02:00
Vishal Aslot
70ac967a7b PCI: ibmphp: Fix double unmap of io_mem
[ Upstream commit faa2e05ad0dccf37f995bcfbb8d1980d66c02c11 ]

ebda_rsrc_controller() calls iounmap(io_mem) on the error path. Its caller,
ibmphp_access_ebda(), also calls iounmap(io_mem) on good and error paths.

Remove the iounmap(io_mem) invocation from ebda_rsrc_controller().

[bhelgaas: remove item from TODO]
Link: https://lore.kernel.org/r/20210818165751.591185-1-os.vaslot@gmail.com
Signed-off-by: Vishal Aslot <os.vaslot@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 12:28:01 +02:00
Lukas Wunner
96c0bf0912 PCI: pciehp: Ignore Link Down/Up caused by DPC
[ Upstream commit a97396c6eb13f65bea894dbe7739b2e883d40a3e ]

Downstream Port Containment (PCIe r5.0, sec. 6.2.10) disables the link upon
an error and attempts to re-enable it when instructed by the DPC driver.

A slot which is both DPC- and hotplug-capable is currently powered off by
pciehp once DPC is triggered (due to the link change) and powered back up
on successful recovery.  That's undesirable, the slot should remain powered
so the hotplugged device remains bound to its driver.  DPC notifies the
driver of the error and of successful recovery in pcie_do_recovery() and
the driver may then restore the device to working state.

Moreover, Sinan points out that turning off slot power by pciehp may foil
recovery by DPC:  Power off/on is a cold reset concurrently to DPC's warm
reset.  Sathyanarayanan reports extended delays or failure in link
retraining by DPC if pciehp brings down the slot.

Fix by detecting whether a Link Down event is caused by DPC and awaiting
recovery if so.  On successful recovery, ignore both the Link Down and the
subsequent Link Up event.

Afterwards, check whether the link is down to detect surprise-removal or
another DPC event immediately after DPC recovery.  Ensure that the
corresponding DLLSC event is not ignored by synthesizing it and invoking
irq_wake_thread() to trigger a re-run of pciehp_ist().

The IRQ threads of the hotplug and DPC drivers, pciehp_ist() and
dpc_handler(), race against each other.  If pciehp is faster than DPC, it
will wait until DPC recovery completes.

Recovery consists of two steps:  The first step (waiting for link
disablement) is recognizable by pciehp through a set DPC Trigger Status
bit.  The second step (waiting for link retraining) is recognizable through
a newly introduced PCI_DPC_RECOVERING flag.

If DPC is faster than pciehp, neither of the two flags will be set and
pciehp may glean the recovery status from the new PCI_DPC_RECOVERED flag.
The flag is zero if DPC didn't occur at all, hence DLLSC events are not
ignored by default.

pciehp waits up to 4 seconds before assuming that DPC recovery failed and
bringing down the slot.  This timeout is not taken from the spec (it
doesn't mandate one) but based on a report from Yicong Yang that DPC may
take a bit more than 3 seconds on HiSilicon's Kunpeng platform.

The timeout is necessary because the DPC Trigger Status bit may never
clear:  On Root Ports which support RP Extensions for DPC, the DPC driver
polls the DPC RP Busy bit for up to 1 second before giving up on DPC
recovery.  Without the timeout, pciehp would then wait indefinitely for DPC
to complete.

This commit draws inspiration from previous attempts to synchronize DPC
with pciehp:

By Sinan Kaya, August 2018:
https://lore.kernel.org/linux-pci/20180818065126.77912-1-okaya@kernel.org/

By Ethan Zhao, October 2020:
https://lore.kernel.org/linux-pci/20201007113158.48933-1-haifeng.zhao@intel.com/

By Kuppuswamy Sathyanarayanan, March 2021:
https://lore.kernel.org/linux-pci/59cb30f5e5ac6d65427ceaadf1012b2ba8dbf66c.1615606143.git.sathyanarayanan.kuppuswamy@linux.intel.com/

Link: https://lore.kernel.org/r/0be565d97438fe2a6d57354b3aa4e8626952a00b.1619857124.git.lukas@wunner.de
Reported-by: Sinan Kaya <okaya@kernel.org>
Reported-by: Ethan Zhao <haifeng.zhao@intel.com>
Reported-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Tested-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:05:47 +02:00
Feilong Lin
dd6ba896ff ACPI / hotplug / PCI: Fix reference count leak in enable_slot()
[ Upstream commit 3bbfd319034ddce59e023837a4aa11439460509b ]

In enable_slot(), if pci_get_slot() returns NULL, we clear the SLOT_ENABLED
flag. When pci_get_slot() finds a device, it increments the device's
reference count.  In this case, we did not call pci_dev_put() to decrement
the reference count, so the memory of the device (struct pci_dev type) will
eventually leak.

Call pci_dev_put() to decrement its reference count when pci_get_slot()
returns a PCI device.

Link: https://lore.kernel.org/r/b411af88-5049-a1c6-83ac-d104a1f429be@huawei.com
Signed-off-by: Feilong Lin <linfeilong@huawei.com>
Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22 11:40:52 +02:00
Tyrel Datwyler
be1f58e58f PCI: rpadlpar: Fix potential drc_name corruption in store functions
commit cc7a0bb058b85ea03db87169c60c7cfdd5d34678 upstream.

Both add_slot_store() and remove_slot_store() try to fix up the
drc_name copied from the store buffer by placing a NUL terminator at
nbyte + 1 or in place of a '\n' if present. However, the static buffer
that we copy the drc_name data into is not zeroed and can contain
anything past the n-th byte.

This is problematic if a '\n' byte appears in that buffer after nbytes
and the string copied into the store buffer was not NUL terminated to
start with as the strchr() search for a '\n' byte will mark this
incorrectly as the end of the drc_name string resulting in a drc_name
string that contains garbage data after the n-th byte.

Additionally it will cause us to overwrite that '\n' byte on the stack
with NUL, potentially corrupting data on the stack.

The following debugging shows an example of the drmgr utility writing
"PHB 4543" to the add_slot sysfs attribute, but add_slot_store()
logging a corrupted string value.

  drmgr: drmgr: -c phb -a -s PHB 4543 -d 1
  add_slot_store: drc_name = PHB 4543°|<82>!, rc = -19

Fix this by using strscpy() instead of memcpy() to ensure the string
is NUL terminated when copied into the static drc_name buffer.
Further, since the string is now NUL terminated the code only needs to
change '\n' to '\0' when present.

Cc: stable@vger.kernel.org
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
[mpe: Reformat change log and add mention of possible stack corruption]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210315214821.452959-1-tyreld@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-25 09:04:16 +01:00
Niklas Schnelle
38c74f2f23 s390/pci: fix leak of PCI device structure
commit 0b13525c20febcfecccf6fc1db5969727401317d upstream.

In commit 05bc1be6db ("s390/pci: create zPCI bus") we removed the
pci_dev_put() call matching the earlier pci_get_slot() done as part of
__zpci_event_availability(). This was based on the wrong understanding
that the device_put() done as part of pci_destroy_device() would counter
the pci_get_slot() when it only counters the initial reference. This
same understanding and existing bad example also lead to not doing
a pci_dev_put() in zpci_remove_device().

Since releasing the PCI devices, unlike releasing the PCI slot, does not
print any debug message for testing I added one in pci_release_dev().
This revealed that we are indeed leaking the PCI device on PCI
hotunplug. Further testing also revealed another missing pci_dev_put() in
disable_slot().

Fix this by adding the missing pci_dev_put() in disable_slot() and fix
zpci_remove_device() with the correct pci_dev_put() calls. Also instead
of calling pci_get_slot() in __zpci_event_availability() to determine if
a PCI device is registered and then doing the same again in
zpci_remove_device() do this once in zpci_remove_device() which makes
sure that the pdev in __zpci_event_availability() is only used for the
result of pci_scan_single_device() which does not need a reference count
decremnt as its ownership goes to the PCI bus.

Also move the check if zdev->zbus->bus is set into zpci_remove_device()
since it may be that we're removing a device with devfn != 0 which never
had a PCI bus. So we can still set the pdev->error_state to indicate
that the device is not usable anymore, add a flag to set the error state.

Fixes: 05bc1be6db ("s390/pci: create zPCI bus")
Cc: <stable@vger.kernel.org> # 5.8+: e1bff843cde6 s390/pci: remove superfluous zdev->zbus check
Cc: <stable@vger.kernel.org> # 5.8+: ba764dd703fe s390/pci: refactor zpci_create_device()
Cc: <stable@vger.kernel.org> # 5.8+
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-25 09:04:05 +01:00
Linus Torvalds
00937f36b0 Merge tag 'pci-v5.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
 "Enumeration:
   - Print IRQ number used by PCIe Link Bandwidth Notification (Dongdong
     Liu)
   - Add schedule point in pci_read_config() to reduce max latency
     (Jiang Biao)
   - Add Kconfig options for MPS/MRRS strategy (Jim Quinlan)

  Resource management:
   - Fix pci_iounmap() memory leak when !CONFIG_GENERIC_IOMAP (Lorenzo
     Pieralisi)

  PCIe native device hotplug:
   - Reduce noisiness on hot removal (Lukas Wunner)

  Power management:
   - Revert "PCI/PM: Apply D2 delay as milliseconds, not microseconds"
     that was done on the basis of spec typo (Bjorn Helgaas)
   - Rename pci_dev.d3_delay to d3hot_delay to remove D3hot/D3cold
     ambiguity (Krzysztof Wilczyński)
   - Remove unused pcibios_pm_ops (Vaibhav Gupta)

  IOMMU:
   - Enable Translation Blocking for external devices to harden against
     DMA attacks (Rajat Jain)

  Error handling:
   - Add an ACPI APEI notifier chain for vendor CPER records to enable
     device-specific error handling (Shiju Jose)

  ASPM:
   - Remove struct aspm_register_info to simplify code (Saheed O.
     Bolarinwa)

  Amlogic Meson PCIe controller driver:
   - Build as module by default (Kevin Hilman)

  Ampere Altra PCIe controller driver:
   - Add MCFG quirk to work around non-standard ECAM implementation
     (Tuan Phan)

  Broadcom iProc PCIe controller driver:
   - Set affinity mask on MSI interrupts (Mark Tomlinson)

  Broadcom STB PCIe controller driver:
   - Make PCIE_BRCMSTB depend on ARCH_BRCMSTB (Jim Quinlan)
   - Add DT bindings for more Brcmstb chips (Jim Quinlan)
   - Add bcm7278 register info (Jim Quinlan)
   - Add bcm7278 PERST# support (Jim Quinlan)
   - Add suspend and resume pm_ops (Jim Quinlan)
   - Add control of rescal reset (Jim Quinlan)
   - Set additional internal memory DMA viewport sizes (Jim Quinlan)
   - Accommodate MSI for older chips (Jim Quinlan)
   - Set bus max burst size by chip type (Jim Quinlan)
   - Add support for bcm7211, bcm7216, bcm7445, bcm7278 (Jim Quinlan)

  Freescale i.MX6 PCIe controller driver:
   - Use dev_err_probe() to reduce redundant messages (Anson Huang)

  Freescale Layerscape PCIe controller driver:
   - Enforce 4K DMA buffer alignment in endpoint test (Hou Zhiqiang)
   - Add DT compatible strings for ls1088a, ls2088a (Xiaowei Bao)
   - Add endpoint support for ls1088a, ls2088a (Xiaowei Bao)
   - Add endpoint test support for lS1088a (Xiaowei Bao)
   - Add MSI-X support for ls1088a (Xiaowei Bao)

  HiSilicon HIP PCIe controller driver:
   - Handle HIP-specific errors via ACPI APEI (Yicong Yang)

  HiSilicon Kirin PCIe controller driver:
   - Return -EPROBE_DEFER if the GPIO isn't ready (Bean Huo)

  Intel VMD host bridge driver:
   - Factor out physical offset, bus offset, IRQ domain, IRQ allocation
     (Jon Derrick)
   - Use generic PCI PM correctly (Jon Derrick)

  Marvell Aardvark PCIe controller driver:
   - Fix compilation on s390 (Pali Rohár)
   - Implement driver 'remove' function and allow to build it as module
     (Pali Rohár)
   - Move PCIe reset card code to advk_pcie_train_link() (Pali Rohár)
   - Convert mvebu a3700 internal SMCC firmware return codes to errno
     (Pali Rohár)
   - Fix initialization with old Marvell's Arm Trusted Firmware (Pali
     Rohár)

  Microsoft Hyper-V host bridge driver:
   - Fix hibernation in case interrupts are not re-created (Dexuan Cui)

  NVIDIA Tegra PCIe controller driver:
   - Stop checking return value of debugfs_create() functions (Greg
     Kroah-Hartman)
   - Convert to use DEFINE_SEQ_ATTRIBUTE macro (Liu Shixin)

  Qualcomm PCIe controller driver:
   - Reset PCIe to work around Qsdk U-Boot issue (Ansuel Smith)

  Renesas R-Car PCIe controller driver:
   - Add DT documentation for r8a774a1, r8a774b1, r8a774e1 endpoints
     (Lad Prabhakar)
   - Add RZ/G2M, RZ/G2N, RZ/G2H IDs to endpoint test (Lad Prabhakar)
   - Add DT support for r8a7742 (Lad Prabhakar)

  Socionext UniPhier Pro5 controller driver:
   - Add DT descriptions of iATU register (host and endpoint) (Kunihiko
     Hayashi)

  Synopsys DesignWare PCIe controller driver:
   - Add link up check in dw_child_pcie_ops.map_bus() (racy, but seems
     unavoidable) (Hou Zhiqiang)
   - Fix endpoint Header Type check so multi-function devices work (Hou
     Zhiqiang)
   - Skip PCIE_MSI_INTR0* programming if MSI is disabled (Jisheng Zhang)
   - Stop leaking MSI page in suspend/resume (Jisheng Zhang)
   - Add common iATU register support instead of keystone-specific code
     (Kunihiko Hayashi)
   - Major config space access and other cleanups in dwc core and
     drivers that use it (al, exynos, histb, imx6, intel-gw, keystone,
     kirin, meson, qcom, tegra) (Rob Herring)
   - Add multiple PFs support for endpoint (Xiaowei Bao)
   - Add MSI-X doorbell mode in endpoint mode (Xiaowei Bao)

  Miscellaneous:
   - Use fallthrough pseudo-keyword (Gustavo A. R. Silva)
   - Fix "0 used as NULL pointer" warnings (Gustavo Pimentel)
   - Fix "cast truncates bits from constant value" warnings (Gustavo
     Pimentel)
   - Remove redundant zeroing for sg_init_table() (Julia Lawall)
   - Use scnprintf(), not snprintf(), in sysfs "show" functions
     (Krzysztof Wilczyński)
   - Remove unused assignments (Krzysztof Wilczyński)
   - Fix "0 used as NULL pointer" warning (Krzysztof Wilczyński)
   - Simplify bool comparisons (Krzysztof Wilczyński)
   - Use for_each_child_of_node() and for_each_node_by_name() (Qinglang
     Miao)
   - Simplify return expressions (Qinglang Miao)"

* tag 'pci-v5.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (147 commits)
  PCI: vmd: Update VMD PM to correctly use generic PCI PM
  PCI: vmd: Create IRQ allocation helper
  PCI: vmd: Create IRQ Domain configuration helper
  PCI: vmd: Create bus offset configuration helper
  PCI: vmd: Create physical offset helper
  PCI: v3-semi: Remove unneeded break
  PCI: dwc: Add link up check in dw_child_pcie_ops.map_bus()
  PCI/ASPM: Remove struct pcie_link_state.l1ss
  PCI/ASPM: Remove struct aspm_register_info.l1ss_cap
  PCI/ASPM: Pass L1SS Capabilities value, not struct aspm_register_info
  PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl1
  PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl2 (unused)
  PCI/ASPM: Remove struct aspm_register_info.l1ss_cap_ptr
  PCI/ASPM: Remove struct aspm_register_info.latency_encoding
  PCI/ASPM: Remove struct aspm_register_info.enabled
  PCI/ASPM: Remove struct aspm_register_info.support
  PCI/ASPM: Use 'parent' and 'child' for readability
  PCI/ASPM: Move LTR path check to where it's used
  PCI/ASPM: Move pci_clear_and_set_dword() earlier
  PCI: dwc: Fix MSI page leakage in suspend/resume
  ...
2020-10-22 12:41:00 -07:00
Krzysztof Wilczyński
23cce2e00b PCI: shpchp: Remove unused 'rc' assignment
The value of the constant POWER_FAILURE assigned to the variable rc
after the power fault check is never used for anything, so remove it.

Addresses-Coverity-ID: 1226899 ("Unused value")
Link: https://lore.kernel.org/r/20200923025225.471459-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-09-28 17:26:02 -05:00
Lukas Wunner
8a61449941 PCI: pciehp: Reduce noisiness on hot removal
When a PCIe card is hot-removed, the Presence Detect State and Data Link
Layer Link Active bits often do not clear simultaneously.  I've seen delays
of up to 244 msec between the two events with Thunderbolt.

After pciehp has brought down the slot in response to the first event, the
other bit may still be set.  It's not discernible whether it's set because
a new card is already in the slot or if it will soon clear.  So pciehp
tries to bring up the slot and in the latter case fails with a bunch of
messages, some of them at KERN_ERR severity.  If the slot is no longer
occupied, the messages are false positives and annoy users.

Stuart Hayes reports the following splat on hot removal:

  KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Link Up
  KERN_INFO pcieport 0000:3c:06.0: pciehp: Timeout waiting for Presence Detect
  KERN_ERR  pcieport 0000:3c:06.0: pciehp: link training error: status 0x0001
  KERN_ERR  pcieport 0000:3c:06.0: pciehp: Failed to check link status

Dongdong Liu complains about a similar splat:

  KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Link Down
  KERN_INFO iommu: Removing device 0000:87:00.0 from group 12
  KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Card present
  KERN_INFO pcieport 0000:80:10.0: Data Link Layer Link Active not set in 1000 msec
  KERN_ERR  pciehp 0000:80:10.0:pcie004: Failed to check link status

Users are particularly irritated to see a bringup attempt even though the
slot was explicitly brought down via sysfs.  In a perfect world, we could
avoid this by setting Link Disable on slot bringdown and re-enabling it
upon a Presence Detect State change.  In reality however, there are broken
hotplug ports which hardwire Presence Detect to zero, see 80696f9914
("PCI: pciehp: Tolerate Presence Detect hardwired to zero").  Conversely,
PCIe r1.0 hotplug ports hardwire Link Active to zero because Link Active
Reporting wasn't specified before PCIe r1.1.  On unplug, some ports first
clear Presence then Link (see Stuart Hayes' splat) whereas others use the
inverse order (see Dongdong Liu's splat).  To top it off, there are hotplug
ports which flap the Presence and Link bits on slot bringup, see
6c35a1ac3d ("PCI: pciehp: Tolerate initially unstable link").

pciehp is designed to work with all of these variants.  Surplus attempts at
slot bringup are a lesser evil than not being able to bring up slots at
all.  Although we could try to perfect the behavior for specific hotplug
controllers, we'd risk breaking others or increasing code complexity.

But we can certainly minimize annoyance by emitting only a single message
with KERN_INFO severity if bringup is unsuccessful:

* Drop the "Timeout waiting for Presence Detect" message in
  pcie_wait_for_presence().  The sole caller of that function,
  pciehp_check_link_status(), ignores the timeout and carries on.  It emits
  error messages of its own and I don't think this particular message adds
  much value.

* There's a single error condition in pciehp_check_link_status() which
  does not emit a message.  Adding one allows dropping the "Failed to check
  link status" message emitted by board_added() if
  pciehp_check_link_status() returns a non-zero integer.

* Tone down all messages in pciehp_check_link_status() to KERN_INFO
  severity and rephrase them to look as innocuous as possible.  To this
  end, move the message emitted by pcie_wait_for_link_delay() to its
  callers.

As a result, Stuart Hayes' splat becomes:

  KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Link Up
  KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Cannot train link: status 0x0001

Dongdong Liu's splat becomes:

  KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Card present
  KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): No link

The messages now merely serve as information that presence or link bits
were set a little longer than expected.  Bringup failures which are not
false positives are still reported, albeit no longer at KERN_ERR severity.

Link: https://lore.kernel.org/linux-pci/20200310182100.102987-1-stuart.w.hayes@gmail.com/
Link: https://lore.kernel.org/linux-pci/1547649064-19019-1-git-send-email-liudongdong3@huawei.com/
Link: https://lore.kernel.org/r/b45e46fd8a6aa6930aaac9d7718c2e4b787a4e5e.1595935071.git.lukas@wunner.de
Reported-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Reported-by: Dongdong Liu <liudongdong3@huawei.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-09-17 16:22:36 -05:00
Qinglang Miao
85d79c5281 PCI: rpadlpar: Use for_each_child_of_node() and for_each_node_by_name()
Use for_each_child_of_node() and for_each_node_by_name() macros instead of
open coding them.

Link: https://lore.kernel.org/r/20200916062128.190819-1-miaoqinglang@huawei.com
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-09-17 16:22:36 -05:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Niklas Schnelle
2f0230b2f2 s390/pci: re-introduce zpci_remove_device()
For fixing the PF to VF link removal we need to perform some action on
every removal of a zdev from the common PCI subsystem.
So in preparation re-introduce zpci_remove_device() and use that instead
of directly calling the common code functions. This  was actually still
declared from earlier code but no longer implemented.

Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-08-17 13:17:25 +02:00
Linus Torvalds
049eb096da Merge tag 'pci-v5.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
 "Enumeration:
   - Fix pci_cfg_wait queue locking problem (Bjorn Helgaas)
   - Convert PCIe capability PCIBIOS errors to errno (Bolarinwa Olayemi
     Saheed)
   - Align PCIe capability and PCI accessor return values (Bolarinwa
     Olayemi Saheed)
   - Fix pci_create_slot() reference count leak (Qiushi Wu)
   - Announce device after early fixups (Tiezhu Yang)

  PCI device hotplug:
   - Make rpadlpar functions static (Wei Yongjun)

  Driver binding:
   - Add device even if driver attach failed (Rajat Jain)

  Virtualization:
   - xen: Remove redundant initialization of irq (Colin Ian King)

  IOMMU:
   - Add pci_pri_supported() to check device or associated PF (Ashok Raj)
   - Release IVRS table in AMD ACS quirk (Hanjun Guo)
   - Mark AMD Navi10 GPU rev 0x00 ATS as broken (Kai-Heng Feng)
   - Treat "external-facing" devices themselves as internal (Rajat Jain)

  MSI:
   - Forward MSI-X error code in pci_alloc_irq_vectors_affinity() (Piotr
     Stankiewicz)

  Error handling:
   - Clear PCIe Device Status errors only if OS owns AER (Jonathan
     Cameron)
   - Log correctable errors as warning, not error (Matt Jolly)
   - Use 'pci_channel_state_t' instead of 'enum pci_channel_state' (Luc
     Van Oostenryck)

  Peer-to-peer DMA:
   - Allow P2PDMA on AMD Zen and newer CPUs (Logan Gunthorpe)

  ASPM:
   - Add missing newline in sysfs 'policy' (Xiongfeng Wang)

  Native PCIe controllers:
   - Convert to devm_platform_ioremap_resource_byname() (Dejin Zheng)
   - Convert to devm_platform_ioremap_resource() (Dejin Zheng)
   - Remove duplicate error message from devm_pci_remap_cfg_resource()
     callers (Dejin Zheng)
   - Fix runtime PM imbalance on error (Dinghao Liu)
   - Remove dev_err() when handing an error from platform_get_irq()
     (Krzysztof Wilczyński)
   - Use pci_host_bridge.windows list directly instead of splicing in a
     temporary list for cadence, mvebu, host-common (Rob Herring)
   - Use pci_host_probe() instead of open-coding all the pieces for
     altera, brcmstb, iproc, mobiveil, rcar, rockchip, tegra, v3,
     versatile, xgene, xilinx, xilinx-nwl (Rob Herring)
   - Default host bridge parent device to the platform device (Rob
     Herring)
   - Use pci_is_root_bus() instead of tracking root bus number
     separately in aardvark, designware (imx6, keystone,
     designware-host), mobiveil, xilinx-nwl, xilinx, rockchip, rcar (Rob
     Herring)
   - Set host bridge bus number in pci_scan_root_bus_bridge() instead of
     each driver for aardvark, designware-host, host-common, mediatek,
     rcar, tegra, v3-semi (Rob Herring)
   - Move DT resource setup into devm_pci_alloc_host_bridge() (Rob
     Herring)
   - Set bridge map_irq and swizzle_irq to default functions; drivers
     that don't support legacy IRQs (iproc) need to undo this (Rob
     Herring)

  ARM Versatile PCIe controller driver:
   - Drop flag PCI_ENABLE_PROC_DOMAINS (Rob Herring)

  Cadence PCIe controller driver:
   - Use "dma-ranges" instead of "cdns,no-bar-match-nbits" property
     (Kishon Vijay Abraham I)
   - Remove "mem" from reg binding (Kishon Vijay Abraham I)
   - Fix cdns_pcie_{host|ep}_setup() error path (Kishon Vijay Abraham I)
   - Convert all r/w accessors to perform only 32-bit accesses (Kishon
     Vijay Abraham I)
   - Add support to start link and verify link status (Kishon Vijay
     Abraham I)
   - Allow pci_host_bridge to have custom pci_ops (Kishon Vijay Abraham I)
   - Add new *ops* for CPU addr fixup (Kishon Vijay Abraham I)
   - Fix updating Vendor ID and Subsystem Vendor ID register (Kishon
     Vijay Abraham I)
   - Use bridge resources for outbound window setup (Rob Herring)
   - Remove private bus number and range storage (Rob Herring)

  Cadence PCIe endpoint driver:
   - Add MSI-X support (Alan Douglas)

  HiSilicon PCIe controller driver:
   - Remove non-ECAM HiSilicon hip05/hip06 driver (Rob Herring)

  Intel VMD host bridge driver:
   - Use Shadow MEMBAR registers for QEMU/KVM guests (Jon Derrick)

  Loongson PCIe controller driver:
   - Use DECLARE_PCI_FIXUP_EARLY for bridge_class_quirk() (Tiezhu Yang)

  Marvell Aardvark PCIe controller driver:
   - Indicate error in 'val' when config read fails (Pali Rohár)
   - Don't touch PCIe registers if no card connected (Pali Rohár)

  Marvell MVEBU PCIe controller driver:
   - Setup BAR0 in order to fix MSI (Shmuel Hazan)

  Microsoft Hyper-V host bridge driver:
   - Fix a timing issue which causes kdump to fail occasionally (Wei Hu)
   - Make some functions static (Wei Yongjun)

  NVIDIA Tegra PCIe controller driver:
   - Revert tegra124 raw_violation_fixup (Nicolas Chauvet)
   - Remove PLL power supplies (Thierry Reding)

  Qualcomm PCIe controller driver:
   - Change duplicate PCI reset to phy reset (Abhishek Sahu)
   - Add missing ipq806x clocks in PCIe driver (Ansuel Smith)
   - Add missing reset for ipq806x (Ansuel Smith)
   - Add ext reset (Ansuel Smith)
   - Use bulk clk API and assert on error (Ansuel Smith)
   - Add support for tx term offset for rev 2.1.0 (Ansuel Smith)
   - Define some PARF params needed for ipq8064 SoC (Ansuel Smith)
   - Add ipq8064 rev2 variant (Ansuel Smith)
   - Support PCI speed set for ipq806x (Sham Muthayyan)

  Renesas R-Car PCIe controller driver:
   - Use devm_pci_alloc_host_bridge() (Rob Herring)
   - Use struct pci_host_bridge.windows list directly (Rob Herring)
   - Convert rcar-gen2 to use modern host bridge probe functions (Rob
     Herring)

  TI J721E PCIe driver:
   - Add TI J721E PCIe host and endpoint driver (Kishon Vijay Abraham I)

  Xilinx Versal CPM PCIe controller driver:
   - Add Versal CPM Root Port driver and YAML schema (Bharat Kumar
     Gogada)

  MicroSemi Switchtec management driver:
   - Add missing __iomem and __user tags to fix sparse warnings (Logan
     Gunthorpe)

  Miscellaneous:
   - Replace http:// links with https:// (Alexander A. Klimov)
   - Replace lkml.org, spinics, gmane with lore.kernel.org (Bjorn
     Helgaas)
   - Remove unused pci_lost_interrupt() (Heiner Kallweit)
   - Move PCI_VENDOR_ID_REDHAT definition to pci_ids.h (Huacai Chen)
   - Fix kerneldoc warnings (Krzysztof Kozlowski)"

* tag 'pci-v5.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits)
  PCI: Fix kerneldoc warnings
  PCI: xilinx-cpm: Add Versal CPM Root Port driver
  PCI: xilinx-cpm: Add YAML schemas for Versal CPM Root Port
  PCI: Set bridge map_irq and swizzle_irq to default functions
  PCI: Move DT resource setup into devm_pci_alloc_host_bridge()
  PCI: rcar-gen2: Convert to use modern host bridge probe functions
  PCI: Remove dev_err() when handing an error from platform_get_irq()
  MAINTAINERS: Add Kishon Vijay Abraham I for TI J721E SoC PCIe
  misc: pci_endpoint_test: Add J721E in pci_device_id table
  PCI: j721e: Add TI J721E PCIe driver
  PCI: switchtec: Add missing __iomem tag to fix sparse warnings
  PCI: switchtec: Add missing __iomem and __user tags to fix sparse warnings
  PCI: rpadlpar: Make functions static
  PCI/P2PDMA: Allow P2PDMA on AMD Zen and newer CPUs
  PCI: Release IVRS table in AMD ACS quirk
  PCI: Announce device after early fixups
  PCI: Mark AMD Navi10 GPU rev 0x00 ATS as broken
  PCI: Remove unused pci_lost_interrupt()
  dt-bindings: PCI: Add EP mode dt-bindings for TI's J721E SoC
  dt-bindings: PCI: Add host mode dt-bindings for TI's J721E SoC
  ...
2020-08-07 18:48:15 -07:00
Bjorn Helgaas
65c2bc6ce9 Merge branch 'pci/doc'
- Fix several kerneldoc warnings (Krzysztof Kozlowski)

* pci/doc:
  PCI: Fix kerneldoc warnings
2020-08-05 18:24:22 -05:00
Krzysztof Kozlowski
9b41d19aff PCI: Fix kerneldoc warnings
Fix kerneldoc warnings, e.g.,

  $ make W=1 drivers/pci/
  drivers/pci/ats.c:196: warning: Function parameter or member 'pdev' not described in 'pci_enable_pri'
  drivers/pci/ats.c:196: warning: Function parameter or member 'reqs' not described in 'pci_enable_pri'
  ...

Link: https://lore.kernel.org/r/20200729201224.26799-2-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-3-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-4-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-5-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-6-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-7-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-08-05 18:23:14 -05:00
Wei Yongjun
2e4770a566 PCI: rpadlpar: Make functions static
The sparse tool report build warnings as follows:

  drivers/pci/hotplug/rpadlpar_core.c:355:5: warning: symbol 'dlpar_remove_pci_slot' was not declared. Should it be static?
  drivers/pci/hotplug/rpadlpar_core.c:461:12: warning: symbol 'rpadlpar_io_init' was not declared. Should it be static?
  drivers/pci/hotplug/rpadlpar_core.c:473:6: warning: symbol 'rpadlpar_io_exit' was not declared. Should it be static?

Those functions are not used outside of this file, so mark them static.

Also mark rpadlpar_io_exit() as __exit.

Link: https://lore.kernel.org/r/20200721151735.41181-1-weiyongjun1@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-07-30 11:11:13 -05:00
Rafael J. Wysocki
dae68d7fd4 PCI: hotplug: ACPI: Fix context refcounting in acpiphp_grab_context()
If context is not NULL in acpiphp_grab_context(), but the
is_going_away flag is set for the device's parent, the reference
counter of the context needs to be decremented before returning
NULL or the context will never be freed, so make that happen.

Fixes: edf5bf34d4 ("ACPI / dock: Use callback pointers from devices' ACPI hotplug contexts")
Reported-by: Vasily Averin <vvs@virtuozzo.com>
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-26 19:42:34 +02:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Linus Torvalds
23fc02e36e Merge tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:

 - Add support for multi-function devices in pci code.

 - Enable PF-VF linking for architectures using the pdev->no_vf_scan
   flag (currently just s390).

 - Add reipl from NVMe support.

 - Get rid of critical section cleanup in entry.S.

 - Refactor PNSO CHSC (perform network subchannel operation) in cio and
   qeth.

 - QDIO interrupts and error handling fixes and improvements, more
   refactoring changes.

 - Align ioremap() with generic code.

 - Accept requests without the prefetch bit set in vfio-ccw.

 - Enable path handling via two new regions in vfio-ccw.

 - Other small fixes and improvements all over the code.

* tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (52 commits)
  vfio-ccw: make vfio_ccw_regops variables declarations static
  vfio-ccw: Add trace for CRW event
  vfio-ccw: Wire up the CRW irq and CRW region
  vfio-ccw: Introduce a new CRW region
  vfio-ccw: Refactor IRQ handlers
  vfio-ccw: Introduce a new schib region
  vfio-ccw: Refactor the unregister of the async regions
  vfio-ccw: Register a chp_event callback for vfio-ccw
  vfio-ccw: Introduce new helper functions to free/destroy regions
  vfio-ccw: document possible errors
  vfio-ccw: Enable transparent CCW IPL from DASD
  s390/pci: Log new handle in clp_disable_fh()
  s390/cio, s390/qeth: cleanup PNSO CHSC
  s390/qdio: remove q->first_to_kick
  s390/qdio: fix up qdio_start_irq() kerneldoc
  s390: remove critical section cleanup from entry.S
  s390: add machine check SIGP
  s390/pci: ioremap() align with generic code
  s390/ap: introduce new ap function ap_get_qdev()
  Documentation/s390: Update / remove developerWorks web links
  ...
2020-06-08 12:05:31 -07:00
Linus Torvalds
3925c3bbdf Merge tag 'pci-v5.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
 "Enumeration:

   - Program MPS for RCiEP devices (Ashok Raj)

   - Fix pci_register_host_bridge() device_register() error handling
     (Rob Herring)

   - Fix pci_host_bridge struct device release/free handling (Rob
     Herring)

  Resource management:

   - Allow resizing BARs for devices on root bus (Ard Biesheuvel)

  Power management:

   - Reduce Thunderbolt resume time by working around devices that don't
     support DLL Link Active reporting (Mika Westerberg)

   - Work around a Pericom USB controller OHCI/EHCI PME# defect
     (Kai-Heng Feng)

  Virtualization:

   - Add ACS quirk for Intel Root Complex Integrated Endpoints (Ashok
     Raj)

   - Avoid FLR for AMD Starship USB 3.0 (Kevin Buettner)

   - Avoid FLR for AMD Matisse HD Audio & USB 3.0 (Marcos Scriven)

  Error handling:

   - Use only _OSC (not HEST FIRMWARE_FIRST) to determine AER ownership
     (Alexandru Gagniuc, Kuppuswamy Sathyanarayanan)

   - Reduce verbosity by logging only ACPI_NOTIFY_DISCONNECT_RECOVER
     events (Kuppuswamy Sathyanarayanan)

   - Don't enable AER by default in Kconfig (Bjorn Helgaas)

  Peer-to-peer DMA:

   - Add AMD Zen Raven and Renoir Root Ports to whitelist (Alex Deucher)

  ASPM:

   - Allow ASPM on links to PCIe-to-PCI/PCI-X Bridges (Kai-Heng Feng)

  Endpoint framework:

   - Fix DMA channel release in test (Kunihiko Hayashi)

   - Add page size as argument to pci_epc_mem_init() (Lad Prabhakar)

   - Add support to handle multiple base for mapping outbound memory
     (Lad Prabhakar)

  Generic host bridge driver:

   - Support building as module (Rob Herring)

   - Eliminate pci_host_common_probe wrappers (Rob Herring)

  Amlogic Meson PCIe controller driver:

   - Don't use FAST_LINK_MODE to set up link (Marc Zyngier)

  Broadcom STB PCIe controller driver:

   - Disable ASPM L0s if 'aspm-no-l0s' in DT (Jim Quinlan)

   - Fix clk_put() error (Jim Quinlan)

   - Fix window register offset (Jim Quinlan)

   - Assert fundamental reset on initialization (Nicolas Saenz Julienne)

   - Add notify xHCI reset property (Nicolas Saenz Julienne)

   - Add init routine for Raspberry Pi 4 VL805 USB controller (Nicolas
     Saenz Julienne)

   - Sync with Raspberry Pi 4 firmware for VL805 initialization (Nicolas
     Saenz Julienne)

  Cadence PCIe controller driver:

   - Remove "cdns,max-outbound-regions" DT property (replaced by
     "ranges") (Kishon Vijay Abraham I)

   - Read 32-bit (not 16-bit) Vendor ID/Device ID property from DT
     (Kishon Vijay Abraham I)

  Marvell Aardvark PCIe controller driver:

   - Improve link training (Marek Behún)

   - Add PHY support (Marek Behún)

   - Add "phys", "max-link-speed", "reset-gpios" to dt-binding (Marek
     Behún)

   - Train link immediately after enabling training to work around
     detection issues with some cards (Pali Rohár)

   - Issue PERST via GPIO to work around detection issues (Pali Rohár)

   - Don't blindly enable ASPM L0s (Pali Rohár)

   - Replace custom macros by standard linux/pci_regs.h macros (Pali
     Rohár)

  Microsoft Hyper-V host bridge driver:

   - Fix probe failure path to release resource (Wei Hu)

   - Retry PCI bus D0 entry on invalid device state for kdump (Wei Hu)

  Renesas R-Car PCIe controller driver:

   - Fix incorrect programming of OB windows (Andrew Murray)

   - Add suspend/resume (Kazufumi Ikeda)

   - Rename pcie-rcar.c to pcie-rcar-host.c (Lad Prabhakar)

   - Add endpoint controller driver (Lad Prabhakar)

   - Fix PCIEPAMR mask calculation (Lad Prabhakar)

   - Add r8a77961 to DT binding (Yoshihiro Shimoda)

  Socionext UniPhier Pro5 controller driver:

   - Add endpoint controller driver (Kunihiko Hayashi)

  Synopsys DesignWare PCIe controller driver:

   - Program outbound ATU upper limit register (Alan Mikhak)

   - Fix inner MSI IRQ domain registration (Marc Zyngier)

  Miscellaneous:

   - Check for platform_get_irq() failure consistently (negative return
     means failure) (Aman Sharma)

   - Fix several runtime PM get/put imbalances (Dinghao Liu)

   - Use flexible-array and struct_size() helpers for code cleanup
     (Gustavo A. R. Silva)

   - Update & fix issues in bridge emulation of PCIe registers (Jon
     Derrick)

   - Add macros for bridge window names (PCI_BRIDGE_IO_WINDOW, etc)
     (Krzysztof Wilczyński)

   - Work around Intel PCH MROMs that have invalid BARs (Xiaochun Lee)"

* tag 'pci-v5.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (100 commits)
  PCI: uniphier: Add Socionext UniPhier Pro5 PCIe endpoint controller driver
  PCI: Add ACS quirk for Intel Root Complex Integrated Endpoints
  PCI/DPC: Print IRQ number used by port
  PCI/AER: Use "aer" variable for capability offset
  PCI/AER: Remove redundant dev->aer_cap checks
  PCI/AER: Remove redundant pci_is_pcie() checks
  PCI/AER: Remove HEST/FIRMWARE_FIRST parsing for AER ownership
  PCI: tegra: Fix runtime PM imbalance on error
  PCI: vmd: Filter resource type bits from shadow register
  PCI: tegra194: Fix runtime PM imbalance on error
  dt-bindings: PCI: Add UniPhier PCIe endpoint controller description
  PCI: hv: Use struct_size() helper
  PCI: Rename _DSM constants to align with spec
  PCI: Avoid FLR for AMD Starship USB 3.0
  PCI: Avoid FLR for AMD Matisse HD Audio & USB 3.0
  x86/PCI: Drop unused xen_register_pirq() gsi_override parameter
  PCI: dwc: Use private data pointer of "struct irq_domain" to get pcie_port
  PCI: amlogic: meson: Don't use FAST_LINK_MODE to set up link
  PCI: dwc: Fix inner MSI IRQ domain registration
  PCI: dwc: pci-dra7xx: Use devm_platform_ioremap_resource_byname()
  ...
2020-06-06 11:01:58 -07:00
Linus Torvalds
118d6e9829 Merge tag 'acpi-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
 "These update the ACPICA code in the kernel to upstream revision
  20200430, fix several reference counting errors related to ACPI
  tables, add _Exx / _Lxx support to the GED driver, add a new
  acpi_evaluate_reg() helper, add new DPTF battery participant driver
  and extend the DPFT power participant driver, improve the handling of
  memory failures in the APEI code, add a blacklist entry to the
  backlight driver, update the PMIC driver and the processor idle
  driver, fix two kobject reference count leaks, and make a few janitory
  changes.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20200430:

      - Move acpi_gbl_next_cmd_num definition (Erik Kaneda).

      - Ignore AE_ALREADY_EXISTS status in the disassembler when parsing
        create operators (Erik Kaneda).

      - Add status checks to the dispatcher (Erik Kaneda).

      - Fix required parameters for _NIG and _NIH (Erik Kaneda).

      - Make acpi_protocol_lengths static (Yue Haibing).

   - Fix ACPI table reference counting errors in several places, mostly
     in error code paths (Hanjun Guo).

   - Extend the Generic Event Device (GED) driver to support _Exx and
     _Lxx handler methods (Ard Biesheuvel).

   - Add new acpi_evaluate_reg() helper and modify the ACPI PCI hotplug
     code to use it (Hans de Goede).

   - Add new DPTF battery participant driver and make the DPFT power
     participant driver create more sysfs device attributes (Srinivas
     Pandruvada).

   - Improve the handling of memory failures in APEI (James Morse).

   - Add new blacklist entry for Acer TravelMate 5735Z to the backlight
     driver (Paul Menzel).

   - Add i2c address for thermal control to the PMIC driver (Mauro
     Carvalho Chehab).

   - Allow the ACPI processor idle driver to work on platforms with only
     one ACPI C-state present (Zhang Rui).

   - Fix kobject reference count leaks in error code paths in two places
     (Qiushi Wu).

   - Delete unused proc filename macros and make some symbols static
     (Pascal Terjan, Zheng Zengkai, Zou Wei)"

* tag 'acpi-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
  ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()
  ACPI: sysfs: Fix reference count leak in acpi_sysfs_add_hotplug_profile()
  ACPI: GED: use correct trigger type field in _Exx / _Lxx handling
  ACPI: DPTF: Add battery participant driver
  ACPI: DPTF: Additional sysfs attributes for power participant driver
  ACPI: video: Use native backlight on Acer TravelMate 5735Z
  arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work
  ACPI: APEI: Kick the memory_failure() queue for synchronous errors
  mm/memory-failure: Add memory_failure_queue_kick()
  ACPI / PMIC: Add i2c address for thermal control
  ACPI: GED: add support for _Exx / _Lxx handler methods
  ACPI: Delete unused proc filename macros
  ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
  ACPI: utils: Add acpi_evaluate_reg() helper
  ACPI: debug: Make two functions static
  ACPI: sleep: Put the FACS table after using it
  ACPI: scan: Put SPCR and STAO table after using it
  ACPI: EC: Put the ACPI table after using it
  ACPI: APEI: Put the HEST table for error path
  ACPI: APEI: Put the error record serialization table for error path
  ...
2020-06-02 13:25:52 -07:00
Krzysztof Wilczynski
cfbd83d02d PCI: shpchp: Make shpchp_unconfigure_device() void
shpchp_unconfigure_device() always returned 0, so there's no reason for a
return value.  In addition, remove_board() checked the return value for
possible error which is unnecessary.

Convert shpchp_unconfigure_device() to a void function and remove the
return value check.  This addresses the following Coccinelle warning:

  drivers/pci/hotplug/shpchp_pci.c:66:5-7: Unneeded variable: "rc".  Return "0" on line 86

Link: https://lore.kernel.org/r/20200521190457.1066600-1-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-05-21 15:23:20 -05:00
Hans de Goede
6dd10c47e9 ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
Use the new acpi_evaluate_reg() helper in the acpiphp_glue.c code.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-09 11:40:25 +02:00
Pierre Morel
53dd462ac4 s390/pci: Do not disable PF when VFs exist
The Physical function should not be disabled until no virtual
functions depends on it.
Let's force the user to first use echo 0 > sriov_numfs before
allowing to disable the PF with echo 0 > power.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:47 +02:00
Pierre Morel
44510d6fa0 s390/pci: Handling multifunctions
We allow multiple functions on a single bus.
We suppress the ZPCI_DEVFN definition and replace its
occurences with zpci->devfn.

We verify the number of device during the registration.

There can never be more domains in use than existing
devices, so we do not need to verify the count of domain
after having verified the count of devices.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:47 +02:00
Pierre Morel
05bc1be6db s390/pci: create zPCI bus
The zPCI bus is in charge to handle common zPCI resources for
zPCI devices.

Creating the zPCI bus, the PCI bus, the zPCI devices and the
PCI devices and hotplug slots
done in a specific order:
- PCI hotplug slot creation needs a PCI bus
- PCI bus needs a PCI domain
  which is reported by the pci_domain_nr() when setting up the
  host bridge
- PCI domain is set from the zPCI with devfn 0
  this is necessary to have a reproducible enumeration

Therefore we can not create devices or hotplug slots for any PCI
device associated with a zPCI device before having discovered
the function zero of the bus.

The discovery and initialization of devices can be done at several
points in the code:
- On Events, serialized in a thread context
- On initialization, in the kernel init thread context
- When powering on the hotplug slot, in a user thread context

The removal of devices and their parent bus may also be done on
events or for devices when powering down the slot.

To guarantee the existence of the bus and devices until they are
no more needed we use kref in zPCI bus and introduce a reference
count in the zPCI devices.

In this patch the zPCI bus still only accept a device with
a devfn 0.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:46 +02:00
Rob Herring
adc9fbcd7d PCI: Use of_node_name_eq() for node name comparisons
Convert string compares of DT node names to use of_node_name_eq() helper
instead. This removes direct access to the node name pointer.

Link: https://lore.kernel.org/r/20200416215114.7715-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
2020-04-24 18:02:17 -05:00
Rafael J. Wysocki
fa2bfead91 PM: sleep: core: Rename dev_pm_smart_suspend_and_suspended()
Because all callers of dev_pm_smart_suspend_and_suspended use it only
for checking whether or not to skip driver suspend callbacks for a
device, rename it to dev_pm_skip_suspend() in analogy with
dev_pm_skip_resume().

No functional impact.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:32:41 +02:00
Ani Sinha
a6cec3fdbd PCI: pciehp: Remove unused EMI() and HP_SUPR_RM() macros
EMI() and HP_SUPR_RM() are unused, so remove them.

Link: https://lore.kernel.org/r/1587439673-39652-1-git-send-email-ani@anisinha.ca
Signed-off-by: Ani Sinha <ani@anisinha.ca>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-04-23 13:45:35 -05:00
Linus Torvalds
d38c07afc3 Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
 "Slightly late as I had to rebase mid-week to insert a bug fix:

   - A large series from Nick for 64-bit to further rework our exception
     vectors, and rewrite portions of the syscall entry/exit and
     interrupt return in C. The result is much easier to follow code
     that is also faster in general.

   - Cleanup of our ptrace code to split various parts out that had
     become badly intertwined with #ifdefs over the years.

   - Changes to our NUMA setup under the PowerVM hypervisor which should
     hopefully avoid non-sensical topologies which can lead to warnings
     from the workqueue code and other problems.

   - MAINTAINERS updates to remove some of our old orphan entries and
     update the status of others.

   - Quite a few other small changes and fixes all over the map.

  Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
  Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
  Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
  Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
  Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
  Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
  Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
  Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
  Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
  Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
  Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
  Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
  Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
  Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
  Datwyler, Vaibhav Jain, YueHaibing"

* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc: Make setjmp/longjmp signature standard
  powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
  powerpc: Suppress .eh_frame generation
  powerpc: Drop -fno-dwarf2-cfi-asm
  powerpc/32: drop unused ISA_DMA_THRESHOLD
  powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
  selftests/powerpc: Fix try-run when source tree is not writable
  powerpc/vmlinux.lds: Explicitly retain .gnu.hash
  powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
  powerpc/ptrace: create ppc_gethwdinfo()
  powerpc/ptrace: create ptrace_get_debugreg()
  powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
  powerpc/ptrace: move register viewing functions out of ptrace.c
  powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
  powerpc/ptrace: split out SPE related functions.
  powerpc/ptrace: split out ALTIVEC related functions.
  powerpc/ptrace: split out VSX related functions.
  powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
  powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
  powerpc/ptrace: remove unused header includes
  ...
2020-04-05 11:12:59 -07:00
Linus Torvalds
ad0bf4eb91 Merge tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:

 - Update maintainers. Niklas Schnelle takes over zpci and Vineeth
   Vijayan common io code.

 - Extend cpuinfo to include topology information.

 - Add new extended counters for IBM z15 and sampling buffer allocation
   rework in perf code.

 - Add control over zeroing out memory during system restart.

 - CCA protected key block version 2 support and other
   fixes/improvements in crypto code.

 - Convert to new fallthrough; annotations.

 - Replace zero-length arrays with flexible-arrays.

 - QDIO debugfs and other small improvements.

 - Drop 2-level paging support optimization for compat tasks. Varios mm
   cleanups.

 - Remove broken and unused hibernate / power management support.

 - Remove fake numa support which does not bring any benefits.

 - Exclude offline CPUs from CPU topology masks to be more consistent
   with other architectures.

 - Prevent last branching instruction address leaking to userspace.

 - Other small various fixes and improvements all over the code.

* tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits)
  s390/mm: cleanup init_new_context() callback
  s390/mm: cleanup virtual memory constants usage
  s390/mm: remove page table downgrade support
  s390/qdio: set qdio_irq->cdev at allocation time
  s390/qdio: remove unused function declarations
  s390/ccwgroup: remove pm support
  s390/ap: remove power management code from ap bus and drivers
  s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc
  s390/mm: cleanup arch_get_unmapped_area() and friends
  s390/ism: remove pm support
  s390/cio: use fallthrough;
  s390/vfio: use fallthrough;
  s390/zcrypt: use fallthrough;
  s390: use fallthrough;
  s390/cpum_sf: Fix wrong page count in error message
  s390/diag: fix display of diagnose call statistics
  s390/ap: Remove ap device suspend and resume callbacks
  s390/pci: Improve handling of unset UID
  s390/pci: Fix zpci_alloc_domain() over allocation
  s390/qdio: pass ISC as parameter to chsc_sadc()
  ...
2020-04-04 09:45:50 -07:00
Stuart Hayes
8edf5332c3 PCI: pciehp: Fix MSI interrupt race
Without this commit, a PCIe hotplug port can stop generating interrupts on
hotplug events, so device adds and removals will not be seen:

The pciehp interrupt handler pciehp_isr() reads the Slot Status register
and then writes back to it to clear the bits that caused the interrupt.  If
a different interrupt event bit gets set between the read and the write,
pciehp_isr() returns without having cleared all of the interrupt event
bits.  If this happens when the MSI isn't masked (which by default it isn't
in handle_edge_irq(), and which it will never be when MSI per-vector
masking is not supported), we won't get any more hotplug interrupts from
that device.

That is expected behavior, according to the PCIe Base Spec r5.0, section
6.7.3.4, "Software Notification of Hot-Plug Events".

Because the Presence Detect Changed and Data Link Layer State Changed event
bits can both get set at nearly the same time when a device is added or
removed, this is more likely to happen than it might seem.  The issue was
found (and can be reproduced rather easily) by connecting and disconnecting
an NVMe storage device on at least one system model where the NVMe devices
were being connected to an AMD PCIe port (PCI device 0x1022/0x1483).

Fix the issue by modifying pciehp_isr() to loop back and re-read the Slot
Status register immediately after writing to it, until it sees that all of
the event status bits have been cleared.

[lukas: drop loop count limitation, write "events" instead of "status",
don't loop back in INTx and poll modes, tweak code comment & commit msg]
Link: https://lore.kernel.org/r/78b4ced5072bfe6e369d20e8b47c279b8c7af12e.1582121613.git.lukas@wunner.de
Tested-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
2020-03-31 10:23:02 -05:00
Lukas Wunner
3e487d2e4a PCI: pciehp: Fix indefinite wait on sysfs requests
David Hoyer reports that powering pciehp slots up or down via sysfs may
hang:  The call to wait_event() in pciehp_sysfs_enable_slot() and
_disable_slot() does not return because ctrl->ist_running remains true.

This flag, which was introduced by commit 157c1062fc ("PCI: pciehp: Avoid
returning prematurely from sysfs requests"), signifies that the IRQ thread
pciehp_ist() is running.  It is set to true at the top of pciehp_ist() and
reset to false at the end.  However there are two additional return
statements in pciehp_ist() before which the commit neglected to reset the
flag to false and wake up waiters for the flag.

That omission opens up the following race when powering up the slot:

* pciehp_ist() runs because a PCI_EXP_SLTSTA_PDC event was requested
  by pciehp_sysfs_enable_slot()

* pciehp_ist() turns on slot power via the following call stack:
  pciehp_handle_presence_or_link_change() -> pciehp_enable_slot() ->
  __pciehp_enable_slot() -> board_added() -> pciehp_power_on_slot()

* after slot power is turned on, the link comes up, resulting in a
  PCI_EXP_SLTSTA_DLLSC event

* the IRQ handler pciehp_isr() stores the event in ctrl->pending_events
  and returns IRQ_WAKE_THREAD

* the IRQ thread is already woken (it's bringing up the slot), but the
  genirq code remembers to re-run the IRQ thread after it has finished
  (such that it can deal with the new event) by setting IRQTF_RUNTHREAD
  via __handle_irq_event_percpu() -> __irq_wake_thread()

* the IRQ thread removes PCI_EXP_SLTSTA_DLLSC from ctrl->pending_events
  via board_added() -> pciehp_check_link_status() in order to deal with
  presence and link flaps per commit 6c35a1ac3d ("PCI: pciehp:
  Tolerate initially unstable link")

* after pciehp_ist() has successfully brought up the slot, it resets
  ctrl->ist_running to false and wakes up the sysfs requester

* the genirq code re-runs pciehp_ist(), which sets ctrl->ist_running
  to true but then returns with IRQ_NONE because ctrl->pending_events
  is empty

* pciehp_sysfs_enable_slot() is finally woken but notices that
  ctrl->ist_running is true, hence continues waiting

The only way to get the hung task going again is to trigger a hotplug
event which brings down the slot, e.g. by yanking out the card.

The same race exists when powering down the slot because remove_board()
likewise clears link or presence changes in ctrl->pending_events per commit
3943af9d01 ("PCI: pciehp: Ignore Link State Changes after powering off a
slot") and thereby may cause a re-run of pciehp_ist() which returns with
IRQ_NONE without resetting ctrl->ist_running to false.

Fix by adding a goto label before the teardown steps at the end of
pciehp_ist() and jumping to that label from the two return statements which
currently neglect to reset the ctrl->ist_running flag.

Fixes: 157c1062fc ("PCI: pciehp: Avoid returning prematurely from sysfs requests")
Link: https://lore.kernel.org/r/cca1effa488065cb055120aa01b65719094bdcb5.1584530321.git.lukas@wunner.de
Reported-by: David Hoyer <David.Hoyer@netapp.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Cc: stable@vger.kernel.org	# v4.19+
2020-03-31 10:22:18 -05:00
Oliver O'Halloran
b6eebb093c powerpc/eeh: Make early EEH init pseries specific
The eeh_ops->probe() function is called from two different contexts:

1. On pseries, where we set EEH_PROBE_MODE_DEVTREE, it's called in
   eeh_add_device_early() which is supposed to run before we create
   a pci_dev.

2. On PowerNV, where we set EEH_PROBE_MODE_DEV, it's called in
   eeh_device_add_late() which is supposed to run *after* the
   pci_dev is created.

The "early" probe is required because PAPR requires that we perform an RTAS
call to enable EEH support on a device before we start interacting with it
via config space or MMIO. This requirement doesn't exist on PowerNV and
shoehorning two completely separate initialisation paths into a common
interface just results in a convoluted code everywhere.

Additionally the early probe requires the probe function to take an pci_dn
rather than a pci_dev argument. We'd like to make pci_dn a pseries specific
data structure since there's no real requirement for them on PowerNV. To
help both goals move the early probe into the pseries containment zone
so the platform depedence is more explicit.

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-5-oohall@gmail.com
2020-03-25 12:09:39 +11:00
Oliver O'Halloran
a4b4f61db8 powerpc/eeh: Do early EEH init only when required
The pci hotplug helper (pci_hp_add_devices()) calls
eeh_add_device_tree_early() to scan the device-tree for new PCI devices and
do the early EEH probe before the device is scanned. This early probe is a
no-op in a lot of cases because:

a) The early init is only required to satisfy a PAPR requirement that EEH
   be configured before we start doing config accesses. On PowerNV it is
   a no-op.

b) It's a no-op for devices that have already had their eeh_dev
   initialised.

There are four callers of pci_hp_add_devices():

1. arch/powerpc/kernel/eeh_driver.c
	Here the hotplug helper is called when re-scanning pci_devs that
	were removed during an EEH recovery pass. The EEH stat for each
	removed device (the eeh_dev) is retained across a recovery pass
	so the early init is a no-op in this case.

2. drivers/pci/hotplug/pnv_php.c
	This is also a no-op since the PowerNV hotplug driver is, suprisingly,
	PowerNV specific.

3. drivers/pci/hotplug/rpaphp_core.c
4. drivers/pci/hotplug/rpaphp_pci.c
	In these two cases new devices have been hotplugged and FW has
	provided new DT nodes for each. These are the only two cases where
	the EEH we might have new PCI device nodes in the DT so these are
	the only two cases where the early EEH probe needs to be done.

We can move the calls to eeh_add_device_tree_early() to the locations where
it's needed and remove it from the generic path. This is preparation for
making the early EEH probe pseries specific.

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-3-oohall@gmail.com
2020-03-25 12:09:38 +11:00
Chen Zhou
9475af081e PCI: rpaphp: Remove unused variable 'value'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/pci/hotplug/rpaphp_core.c: In function is_php_type:
drivers/pci/hotplug/rpaphp_core.c:291:16: warning:
	variable value set but not used [-Wunused-but-set-variable]

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200312140412.32373-1-chenzhou10@huawei.com
2020-03-25 12:09:27 +11:00
Pierre Morel
035f212fa7 s390/pci: embedding hotplug_slot in zdev
Embedding the hotplug_slot in zdev structure allows to
greatly simplify the hotplug handling by eliminating
the handling of the slot_list.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-10 15:16:25 +01:00
Stuart Hayes
0b382546d8 PCI: pciehp: Add DMI table for in-band presence detection disabled
Some systems have in-band presence detection disabled for hot-plug PCI
slots but do not report this in the slot capabilities 2 (SLTCAP2) register.
On these systems, presence detect can become active well after the link is
reported to be active, which can cause the slots to be disabled after a
device is connected.

Add a DMI table to flag these systems as having in-band presence detect
disabled.

Link: https://lore.kernel.org/r/20191025190047.38130-4-stuart.w.hayes@gmail.com
Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2020-02-20 22:48:45 -06:00
Alexandru Gagniuc
f496648b99 PCI: pciehp: Wait for PDS if in-band presence is disabled
When in-band presence detect is disabled, PDS may come up at any time or
not at all.  PDS being low may indicate that the card is still mating, and
we could expect contact bounce to bring down the link as well.

It is reasonable to assume that most cards will mate in a hotplug slot in
about a second.  Thus, when we know PDS only reflects out-of-band presence
detect, it's worthwhile to wait the extra second or so to make sure the
card is properly mated before loading the driver and to prevent the hotplug
code from disabling a device if the presence detect change goes active
after the device is enabled.

Link: https://lore.kernel.org/r/20191025190047.38130-3-stuart.w.hayes@gmail.com
[bhelgaas: use ctrl_info() instead of pci_info()]
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2020-02-20 22:47:29 -06:00
Alexandru Gagniuc
202853595e PCI: pciehp: Disable in-band presence detect when possible
The presence detect state (PDS) is normally a logical OR of in-band and
out-of-band (OOB) presence detect.  As of PCIe 4.0, there is the option to
disable in-band presence so that the PDS bit always reflects the state of
the out-of-band presence.

The recommendation of the PCIe spec is to disable in-band presence whenever
supported (PCIe r5.0, appendix I implementation note):

  Due to architectural issues, the in-band (Physical-Layer-based) portion
  of the PD mechanism is deprecated for use with async hot-plug. One issue
  is that in-band PD as architected does not detect adapter removal during
  certain LTSSM states, notably the L1 and Disabled States.  Another issue
  is that when both in-band and OOB PD are being used together, the
  Presence Detect State bit and its associated interrupt mechanism always
  reflect the logical OR of the inband and OOB PD states, and with some
  hot-plug hardware configurations, it is important for software to detect
  and respond to in-band and OOB PD events independently.  If OOB PD is
  being used and the associated DSP supports In-Band PD Disable, it is
  recommended that the In-Band PD Disable bit be Set, and the Presence
  Detect State bit and its associated interrupt mechanism be used
  exclusively for OOB PD.  As a substitute for in-band PD with async
  hot-plug, the reference model uses either the DPC or the DLL Link Active
  mechanism.

Link: https://lore.kernel.org/r/20191025190047.38130-2-stuart.w.hayes@gmail.com
[bhelgaas: move PCI_EXP_SLTCAP2 read earlier & print PCI_EXP_SLTCAP2_IBPD
value (suggested by Lukas)]
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2020-02-20 22:44:30 -06:00
Frederic Barrat
748ac391ab pci/hotplug/pnv-php: Wrap warnings in macro
An opencapi slot doesn't have an associated bridge device. It's not
needed for operation, but any warning is displayed through pci_warn()
which uses the pci_dev struct of the assocated bridge device. So wrap
those warning so that a different trace mechanism can be used if it's
an opencapi slot.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-11-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00