linux-stable.git/drivers/pci, branch v5.4.239

PCI: Unify delay handling for reset and resume

2023-03-22T12:28:09+00:00

commit ac91e6980563ed53afadd925fa6585ffd2bc4a2c upstream.

Sheng Bi reports that pci_bridge_secondary_bus_reset() may fail to wait
for devices on the secondary bus to become accessible after reset:

Although it does call pci_dev_wait(), it erroneously passes the bridge's
pci_dev rather than that of a child.  The bridge of course is always
accessible while its secondary bus is reset, so pci_dev_wait() returns
immediately.

Sheng Bi proposes introducing a new pci_bridge_secondary_bus_wait()
function which is called from pci_bridge_secondary_bus_reset():

https://lore.kernel.org/linux-pci/20220523171517.32407-1-windy.bi.enflame@gmail.com/

However we already have pci_bridge_wait_for_secondary_bus() which does
almost exactly what we need.  So far it's only called on resume from
D3cold (which implies a Fundamental Reset per PCIe r6.0 sec 5.8).
Re-using it for Secondary Bus Resets is a leaner and more rational
approach than introducing a new function.

That only requires a few minor tweaks:

- Amend pci_bridge_wait_for_secondary_bus() to await accessibility of
  the first device on the secondary bus by calling pci_dev_wait() after
  performing the prescribed delays.  pci_dev_wait() needs two parameters,
  a reset reason and a timeout, which callers must now pass to
  pci_bridge_wait_for_secondary_bus().  The timeout is 1 sec for resume
  (PCIe r6.0 sec 6.6.1) and 60 sec for reset (commit 821cdad5c46c ("PCI:
  Wait up to 60 seconds for device to become ready after FLR")).
  Introduce a PCI_RESET_WAIT macro for the 1 sec timeout.

- Amend pci_bridge_wait_for_secondary_bus() to return 0 on success or
  -ENOTTY on error for consumption by pci_bridge_secondary_bus_reset().

- Drop an unnecessary 1 sec delay from pci_reset_secondary_bus() which
  is now performed by pci_bridge_wait_for_secondary_bus().  A static
  delay this long is only necessary for Conventional PCI, so modern
  PCIe systems benefit from shorter reset times as a side effect.

Fixes: 6b2f1351af56 ("PCI: Wait for device to become ready after secondary bus reset")
Link: https://lore.kernel.org/r/da77c92796b99ec568bd070cbe4725074a117038.1673769517.git.lukas@wunner.de
Reported-by: Sheng Bi 
Tested-by: Ravi Kishore Koppuravuri 
Signed-off-by: Lukas Wunner 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Mika Westerberg 
Reviewed-by: Kuppuswamy Sathyanarayanan 
Cc: stable@vger.kernel.org # v4.17+
Signed-off-by: Greg Kroah-Hartman

PCI: Add ACS quirk for Wangxun NICs

2023-03-11T15:44:15+00:00

[ Upstream commit a2b9b123ccac913e9f9b80337d687a2fe786a634 ]

Wangxun has verified there is no peer-to-peer between functions for the
below selection of SFxxx, RP1000 and RP2000 NICS.  They may be
multi-function devices, but the hardware does not advertise ACS capability.

Add an ACS quirk for these devices so the functions can be in independent
IOMMU groups.

Link: https://lore.kernel.org/r/20230207102419.44326-1-mengyuanlou@net-swift.com
Signed-off-by: Mengyuan Lou 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin

PCI: Avoid FLR for AMD FCH AHCI adapters

2023-03-11T15:44:07+00:00

commit 63ba51db24ed1b8f8088a897290eb6c036c5435d upstream.

PCI passthrough to VMs does not work with AMD FCH AHCI adapters: the guest
OS fails to correctly probe devices attached to the controller due to FIS
communication failures:

  ata4: softreset failed (1st FIS failed)
  ...
  ata4.00: qc timeout after 5000 msecs (cmd 0xec)
  ata4.00: failed to IDENTIFY (I/O error, err_mask=0x4)

Forcing the "bus" reset method before unbinding & binding the adapter to
the vfio-pci driver solves this issue, e.g.:

  echo "bus" > /sys/bus/pci/devices//reset_method

gives a working guest OS, indicating that the default FLR reset method
doesn't work correctly.

Apply quirk_no_flr() to AMD FCH AHCI devices to work around this issue.

Link: https://lore.kernel.org/r/20230128013951.523247-1-damien.lemoal@opensource.wdc.com
Reported-by: Niklas Cassel 
Signed-off-by: Damien Le Moal 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI: hotplug: Allow marking devices as disconnected during bind/unbind

2023-03-11T15:44:07+00:00

commit 74ff8864cc842be994853095dba6db48e716400a upstream.

On surprise removal, pciehp_unconfigure_device() and acpiphp's
trim_stale_devices() call pci_dev_set_disconnected() to mark removed
devices as permanently offline.  Thereby, the PCI core and drivers know
to skip device accesses.

However pci_dev_set_disconnected() takes the device_lock and thus waits for
a concurrent driver bind or unbind to complete.  As a result, the driver's
->probe and ->remove hooks have no chance to learn that the device is gone.

That doesn't make any sense, so drop the device_lock and instead use atomic
xchg() and cmpxchg() operations to update the device state.

As a byproduct, an AB-BA deadlock reported by Anatoli is fixed which occurs
on surprise removal with AER concurrently performing a bus reset.

AER bus reset:

  INFO: task irq/26-aerdrv:95 blocked for more than 120 seconds.
  Tainted: G        W          6.2.0-rc3-custom-norework-jan11+
  schedule
  rwsem_down_write_slowpath
  down_write_nested
  pciehp_reset_slot                      # acquires reset_lock
  pci_reset_hotplug_slot
  pci_slot_reset                         # acquires device_lock
  pci_bus_error_reset
  aer_root_reset
  pcie_do_recovery
  aer_process_err_devices
  aer_isr

pciehp surprise removal:

  INFO: task irq/26-pciehp:96 blocked for more than 120 seconds.
  Tainted: G        W          6.2.0-rc3-custom-norework-jan11+
  schedule_preempt_disabled
  __mutex_lock
  mutex_lock_nested
  pci_dev_set_disconnected               # acquires device_lock
  pci_walk_bus
  pciehp_unconfigure_device
  pciehp_disable_slot
  pciehp_handle_presence_or_link_change
  pciehp_ist                             # acquires reset_lock

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215590
Fixes: a6bd101b8f84 ("PCI: Unify device inaccessible")
Link: https://lore.kernel.org/r/3dc88ea82bdc0e37d9000e413d5ebce481cbd629.1674205689.git.lukas@wunner.de
Reported-by: Anatoli Antonovitch 
Signed-off-by: Lukas Wunner 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org # v4.20+
Cc: Keith Busch 
Signed-off-by: Greg Kroah-Hartman

PCI/PM: Observe reset delay irrespective of bridge_d3

2023-03-11T15:44:06+00:00

commit 8ef0217227b42e2c34a18de316cee3da16c9bf1e upstream.

If a PCI bridge is suspended to D3cold upon entering system sleep,
resuming it entails a Fundamental Reset per PCIe r6.0 sec 5.8.

The delay prescribed after a Fundamental Reset in PCIe r6.0 sec 6.6.1
is sought to be observed by:

  pci_pm_resume_noirq()
    pci_pm_bridge_power_up_actions()
      pci_bridge_wait_for_secondary_bus()

However, pci_bridge_wait_for_secondary_bus() bails out if the bridge_d3
flag is not set.  That flag indicates whether a bridge is allowed to
suspend to D3cold at *runtime*.

Hence *no* delay is observed on resume from system sleep if runtime
D3cold is forbidden.  That doesn't make any sense, so drop the bridge_d3
check from pci_bridge_wait_for_secondary_bus().

The purpose of the bridge_d3 check was probably to avoid delays if a
bridge remained in D0 during suspend.  However the sole caller of
pci_bridge_wait_for_secondary_bus(), pci_pm_bridge_power_up_actions(),
is only invoked if the previous power state was D3cold.  Hence the
additional bridge_d3 check seems superfluous.

Fixes: ad9001f2f411 ("PCI/PM: Add missing link delays required by the PCIe spec")
Link: https://lore.kernel.org/r/eb37fa345285ec8bacabbf06b020b803f77bdd3d.1673769517.git.lukas@wunner.de
Tested-by: Ravi Kishore Koppuravuri 
Signed-off-by: Lukas Wunner 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Mika Westerberg 
Reviewed-by: Kuppuswamy Sathyanarayanan 
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Greg Kroah-Hartman

PCI/sysfs: Fix double free in error path

2023-01-18T10:41:49+00:00

commit aa382ffa705bea9931ec92b6f3c70e1fdb372195 upstream.

When pci_create_attr() fails, pci_remove_resource_files() is called which
will iterate over the res_attr[_wc] arrays and frees every non NULL entry.
To avoid a double free here set the array entry only after it's clear we
successfully initialized it.

Fixes: b562ec8f74e4 ("PCI: Don't leak memory if sysfs_create_bin_file() fails")
Link: https://lore.kernel.org/r/20221007070735.GX986@pengutronix.de/
Signed-off-by: Sascha Hauer 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI: Fix pci_device_is_present() for VFs by checking PF

2023-01-18T10:41:49+00:00

commit 98b04dd0b4577894520493d96bc4623387767445 upstream.

pci_device_is_present() previously didn't work for VFs because it reads the
Vendor and Device ID, which are 0xffff for VFs, which looks like they
aren't present.  Check the PF instead.

Wei Gong reported that if virtio I/O is in progress when the driver is
unbound or "0" is written to /sys/.../sriov_numvfs, the virtio I/O
operation hangs, which may result in output like this:

  task:bash state:D stack:    0 pid: 1773 ppid:  1241 flags:0x00004002
  Call Trace:
   schedule+0x4f/0xc0
   blk_mq_freeze_queue_wait+0x69/0xa0
   blk_mq_freeze_queue+0x1b/0x20
   blk_cleanup_queue+0x3d/0xd0
   virtblk_remove+0x3c/0xb0 [virtio_blk]
   virtio_dev_remove+0x4b/0x80
   ...
   device_unregister+0x1b/0x60
   unregister_virtio_device+0x18/0x30
   virtio_pci_remove+0x41/0x80
   pci_device_remove+0x3e/0xb0

This happened because pci_device_is_present(VF) returned "false" in
virtio_pci_remove(), so it called virtio_break_device().  The broken vq
meant that vring_interrupt() skipped the vq.callback() that would have
completed the virtio I/O operation via virtblk_done().

[bhelgaas: commit log, simplify to always use pci_physfn(), add stable tag]
Link: https://lore.kernel.org/r/20221026060912.173250-1-mst@redhat.com
Reported-by: Wei Gong 
Tested-by: Wei Gong 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI: Check for alloc failure in pci_request_irq()

2023-01-18T10:41:18+00:00

[ Upstream commit 2d9cd957d40c3ac491b358e7cff0515bb07a3a9c ]

When kvasprintf() fails to allocate memory, it returns a NULL pointer.
Return error from pci_request_irq() so we don't dereference it.

[bhelgaas: commit log]
Fixes: 704e8953d3e9 ("PCI/irq: Add pci_request_irq() and pci_free_irq() helpers")
Link: https://lore.kernel.org/r/20221121020029.3759444-1-zengheng4@huawei.com
Signed-off-by: Zeng Heng 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

PCI: Sanitise firmware BAR assignments behind a PCI-PCI bridge

2022-10-26T11:22:16+00:00

commit 0e32818397426a688f598f35d3bc762eca6d7592 upstream.

When pci_assign_resource() is unable to assign resources to a BAR, it uses
pci_revert_fw_address() to fall back to a firmware assignment (if any).
Previously pci_revert_fw_address() assumed all addresses could reach the
device, but this is not true if the device is below a bridge that only
forwards addresses within its windows.

This problem was observed on a Tyan Tomcat IV S1564D system where the BIOS
did not assign valid addresses to several bridges and USB devices:

  pci 0000:00:11.0: PCI-to-PCIe bridge to [bus 01-ff]
  pci 0000:00:11.0:   bridge window [io  0xe000-0xefff]
  pci 0000:01:00.0: PCIe Upstream Port to [bus 02-ff]
  pci 0000:01:00.0:   bridge window [io  0x0000-0x0fff]   # unreachable
  pci 0000:02:02.0: PCIe Downstream Port to [bus 05-ff]
  pci 0000:02:02.0:   bridge window [io  0x0000-0x0fff]   # unreachable
  pci 0000:05:00.0: PCIe-to-PCI bridge to [bus 06-ff]
  pci 0000:05:00.0:   bridge window [io  0x0000-0x0fff]   # unreachable
  pci 0000:06:08.0: USB UHCI 1.1
  pci 0000:06:08.0: BAR 4: [io  0xfce0-0xfcff]            # unreachable
  pci 0000:06:08.1: USB UHCI 1.1
  pci 0000:06:08.1: BAR 4: [io  0xfce0-0xfcff]            # unreachable
  pci 0000:06:08.0: can't claim BAR 4 [io  0xfce0-0xfcff]: no compatible bridge window
  pci 0000:06:08.1: can't claim BAR 4 [io  0xfce0-0xfcff]: no compatible bridge window

During the first pass of assigning unassigned resources, there was not
enough I/O space available, so we couldn't assign the 06:08.0 BAR and
reverted to the firmware assignment (still unreachable).  Reverting the
06:08.1 assignment failed because it conflicted with 06:08.0:

  pci 0000:00:11.0:   bridge window [io  0xe000-0xefff]
  pci 0000:01:00.0: no space for bridge window [io  size 0x2000]
  pci 0000:02:02.0: no space for bridge window [io  size 0x1000]
  pci 0000:05:00.0: no space for bridge window [io  size 0x1000]
  pci 0000:06:08.0: BAR 4: no space for [io  size 0x0020]
  pci 0000:06:08.0: BAR 4: trying firmware assignment [io  0xfce0-0xfcff]
  pci 0000:06:08.1: BAR 4: no space for [io  size 0x0020]
  pci 0000:06:08.1: BAR 4: trying firmware assignment [io  0xfce0-0xfcff]
  pci 0000:06:08.1: BAR 4: [io  0xfce0-0xfcff] conflicts with 0000:06:08.0 [io  0xfce0-0xfcff]

A subsequent pass assigned valid bridge windows and a valid 06:08.1 BAR,
but left the 06:08.0 BAR alone, so the UHCI device was still unusable:

  pci 0000:00:11.0:   bridge window [io  0xe000-0xefff] released
  pci 0000:00:11.0:   bridge window [io  0x1000-0x2fff]   # reassigned
  pci 0000:01:00.0:   bridge window [io  0x1000-0x2fff]   # reassigned
  pci 0000:02:02.0:   bridge window [io  0x2000-0x2fff]   # reassigned
  pci 0000:05:00.0:   bridge window [io  0x2000-0x2fff]   # reassigned
  pci 0000:06:08.0: BAR 4: assigned [io  0xfce0-0xfcff]   # left alone
  pci 0000:06:08.1: BAR 4: assigned [io  0x2000-0x201f]
  ...
  uhci_hcd 0000:06:08.0: host system error, PCI problems?
  uhci_hcd 0000:06:08.0: host controller process error, something bad happened!
  uhci_hcd 0000:06:08.0: host controller halted, very bad!
  uhci_hcd 0000:06:08.0: HCRESET not completed yet!
  uhci_hcd 0000:06:08.0: HC died; cleaning up

If the address assigned by firmware is not reachable because it's not
within upstream bridge windows, fail instead of assigning the unusable
address from firmware.

[bhelgaas: commit log, use pci_upstream_bridge()]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=16263
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203012338460.46819@angie.orcam.me.uk
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209211921250.29493@angie.orcam.me.uk
Fixes: 58c84eda0756 ("PCI: fall back to original BIOS BAR addresses")
Signed-off-by: Maciej W. Rozycki 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org # v2.6.35+
Signed-off-by: Greg Kroah-Hartman

PCI: Add ACS quirk for Broadcom BCM5750x NICs

2022-08-25T09:18:31+00:00

[ Upstream commit afd306a65cedb9589564bdb23a0c368abc4215fd ]

The Broadcom BCM5750x NICs may be multi-function devices.  They do not
advertise ACS capability. Peer-to-peer transactions are not possible
between the individual functions, so it is safe to treat them as fully
isolated.

Add an ACS quirk for these devices so the functions can be in independent
IOMMU groups and attached individually to userspace applications using
VFIO.

Link: https://lore.kernel.org/r/1654796507-28610-1-git-send-email-michael.chan@broadcom.com
Signed-off-by: Pavan Chebbi 
Signed-off-by: Michael Chan 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin