Commit graph

1400 commits

Author SHA1 Message Date
Gerd Bayer
bcb5d6c769 s390/pci: introduce lock to synchronize state of zpci_dev's
There's a number of tasks that need the state of a zpci device
to be stable. Other tasks need to be synchronized as they change the state.

State changes could be generated by the system as availability or error
events, or be requested by the user through manipulations in sysfs.
Some other actions accessible through sysfs - like device resets - need the
state to be stable.

Unsynchronized state handling could lead to unusable devices. This has
been observed in cases of concurrent state changes through systemd udev
rules and DPM boot control. Some breakage can be provoked by artificial
tests, e.g. through repetitively injecting "recover" on a PCI function
through sysfs while running a "hotplug remove/add" in a loop through a
PCI slot's "power" attribute in sysfs. After a few iterations this could
result in a kernel oops.

So introduce a new mutex "state_lock" to guard the state property of the
struct zpci_dev. Acquire this lock in all task that modify the state:

- hotplug add and remove, through the PCI hotplug slot entry,
- avaiability events, as reported by the platform,
- error events, as reported by the platform,
- during device resets, explicit through sysfs requests or
  implict through the common PCI layer.

Break out an inner _do_recover() routine out of recover_store() to
separte the necessary synchronizations from the actual manipulations of
the zpci_dev required for the reset.

With the following changes I was able to run the inject loops for hours
without hitting an error.

Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-20 14:37:32 +01:00
Bjorn Helgaas
5df12742b7 Revert "PCI: acpiphp: Reassign resources on bridge if necessary"
This reverts commit 40613da52b and the
subsequent fix to it:

  cc22522fd5 ("PCI: acpiphp: Use pci_assign_unassigned_bridge_resources() only for non-root bus")

40613da52b fixed a problem where hot-adding a device with large BARs
failed if the bridge windows programmed by firmware were not large enough.

cc22522fd5 ("PCI: acpiphp: Use pci_assign_unassigned_bridge_resources()
only for non-root bus") fixed a problem with 40613da52b: an ACPI hot-add
of a device on a PCI root bus (common in the virt world) or firmware
sending ACPI Bus Check to non-existent Root Ports (e.g., on Dell Inspiron
7352/0W6WV0) caused a NULL pointer dereference and suspend/resume hangs.

Unfortunately the combination of 40613da52b and cc22522fd5 caused other
problems:

  - Fiona reported that hot-add of SCSI disks in QEMU virtual machine fails
    sometimes.

  - Dongli reported a similar problem with hot-add of SCSI disks.

  - Jonathan reported a console freeze during boot on bare metal due to an
    error in radeon GPU initialization.

Revert both patches to avoid adding these problems.  This means we will
again see the problems with hot-adding devices with large BARs and the NULL
pointer dereferences and suspend/resume issues that 40613da52b and
cc22522fd5 were intended to fix.

Fixes: 40613da52b ("PCI: acpiphp: Reassign resources on bridge if necessary")
Fixes: cc22522fd5 ("PCI: acpiphp: Use pci_assign_unassigned_bridge_resources() only for non-root bus")
Reported-by: Fiona Ebner <f.ebner@proxmox.com>
Closes: https://lore.kernel.org/r/9eb669c0-d8f2-431d-a700-6da13053ae54@proxmox.com
Reported-by: Dongli Zhang <dongli.zhang@oracle.com>
Closes: https://lore.kernel.org/r/3c4a446a-b167-11b8-f36f-d3c1b49b42e9@oracle.com
Reported-by: Jonathan Woithe <jwoithe@just42.net>
Closes: https://lore.kernel.org/r/ZXpaNCLiDM+Kv38H@marvin.atrad.com.au
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Cc: <stable@vger.kernel.org>
2023-12-15 14:55:10 -06:00
Bjorn Helgaas
5897c17402 Merge branch 'pci/field-get'
- Use FIELD_GET()/FIELD_PREP() when possible throughout drivers/pci/ (Ilpo
  Järvinen, Bjorn Helgaas)

- Rework DPC control programming for clarity (Ilpo Järvinen)

* pci/field-get:
  PCI/portdrv: Use FIELD_GET()
  PCI/VC: Use FIELD_GET()
  PCI/PTM: Use FIELD_GET()
  PCI/PME: Use FIELD_GET()
  PCI/ATS: Use FIELD_GET()
  PCI/ATS: Show PASID Capability register width in bitmasks
  PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirk
  PCI: Use FIELD_GET()
  PCI/MSI: Use FIELD_GET/PREP()
  PCI/DPC: Use defines with DPC reason fields
  PCI/DPC: Use defined fields with DPC_CTL register
  PCI/DPC: Use FIELD_GET()
  PCI: hotplug: Use FIELD_GET/PREP()
  PCI: dwc: Use FIELD_GET/PREP()
  PCI: cadence: Use FIELD_GET()
  PCI: Use FIELD_GET() to extract Link Width
  PCI: mvebu: Use FIELD_PREP() with Link Width
  PCI: tegra194: Use FIELD_GET()/FIELD_PREP() with Link Width fields

# Conflicts:
#	drivers/pci/controller/dwc/pcie-tegra194.c
2023-10-28 13:31:05 -05:00
Bjorn Helgaas
adfe8d727d Merge branch 'pci/hotplug'
- Add driver for Ampere Altra Attention Indicators (D Scott Phillips)

* pci/hotplug:
  PCI: hotplug: Add Ampere Altra Attention Indicator extension driver
  PCI: acpiphp: Allow built-in drivers for Attention Indicators
2023-10-28 13:30:58 -05:00
D Scott Phillips
820f59ed96 PCI: hotplug: Add Ampere Altra Attention Indicator extension driver
On Ampere Altra, PCIe hotplug is handled through ACPI. A side interface is
also present to request system firmware control of the hotplug Attention
Indicators. Add an ACPI PCI Hotplug companion driver to support Attention
Indicator control.

Link: https://lore.kernel.org/r/20230930002036.6491-2-scott@os.amperecomputing.com
Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
[bhelgaas: mask domain to low 4 bits]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
2023-10-26 06:02:10 -05:00
D Scott Phillips
33883eeda4 PCI: acpiphp: Allow built-in drivers for Attention Indicators
Since the introduction of the attention callback in acpiphp, a non-zero
struct module *owner has been required in acpiphp_register_attention(). The
intent seemed to be that the core code could hold a refcount on the module
while invoking a callback.

This check accidentally precludes the possibility of attention callbacks to
built-in drivers.

Remove the check on `struct module *owner` in acpiphp_register_attention()
so attention callbacks can also be registered from built-in drivers.

Link: https://lore.kernel.org/r/20230930002036.6491-1-scott@os.amperecomputing.com
Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-10-25 13:05:37 -05:00
Ilpo Järvinen
abaaac4845 PCI: hotplug: Use FIELD_GET/PREP()
Instead of handcrafted shifts to handle register fields, use
FIELD_GET/FIELD_PREP().

Link: https://lore.kernel.org/r/20231018113254.17616-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-10-24 10:54:04 -05:00
Ilpo Järvinen
83c088148c PCI: Use PCI_HEADER_TYPE_* instead of literals
Replace literals under drivers/pci/ with PCI_HEADER_TYPE_MASK,
PCI_HEADER_TYPE_NORMAL, and PCI_HEADER_TYPE_MFD.

Also replace !! boolean conversions with FIELD_GET().

Link: https://lore.kernel.org/r/20231003125300.5541-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> # for Renesas R-Car
2023-10-03 11:55:59 -05:00
Linus Torvalds
4ad0a4c234 powerpc updates for 6.6
- Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
    configured SMT state when hotplugging CPUs into the system.
 
  - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the Radix
    MMU to avoid a broadcast TLBIE flush on exit.
 
  - Drop the exclusion between ptrace/perf watchpoints, and drop the now unused
    associated arch hooks.
 
  - Add support for the "nohlt" command line option to disable CPU idle.
 
  - Add support for -fpatchable-function-entry for ftrace, with GCC >= 13.1.
 
  - Rework memory block size determination, and support 256MB size on systems
    with GPUs that have hotpluggable memory.
 
  - Various other small features and fixes.
 
 Thanks to: Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev,
 Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam Menghani, Geoff Levand,
 Hari Bathini, Immad Mir, Jialin Zhang, Joel Stanley, Jordan Niethe, Justin
 Stitt, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He,
 Linus Walleij, Mahesh Salgaonkar, Masahiro Yamada, Michal Suchanek, Nageswara
 R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick
 Desaulniers, Omar Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell
 Currey, Sourabh Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav
 Jain, Xiongfeng Wang, Yuan Tan, Zhang Rui, Zheng Zengkai.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEJFGtCPCthwEv2Y/bUevqPMjhpYAFAmTwgbwTHG1wZUBlbGxl
 cm1hbi5pZC5hdQAKCRBR6+o8yOGlgFmpD/432vipeoqvkAYsyK0xi/Y3GcY0wcyd
 WJApLXXadEbtKQrgXQ6sowWqalg5thYnQCRarg/tXKK/po3KfgwkPjGDpOL+cIdr
 12QVN2XJm9VmJ1wYJxzk+yXx4F43AdmMdr94qWAGufbTHezwb4UpzVR1NxtFrOE/
 X5TNsC2+2mdZY/ZaNHS5vsTIFv3EhQfqgjZPlIAdLn6CGc8xWT514Q/uHA8+ytM/
 HL7Hqs33DoPSvgTa5TT/2E0d0k5nO3P5KObzAjpYlireTPaBi51mpKGewcrtm0o2
 v3cBlbfx3C7pe9ZhKBK9BH8cjynfiqsVZ9/lCw/7eBNdm9tHuzG0jeS7Db9tCZXS
 fM7G2R7SoIusPTqxlBmkU5DpYslwrHiVgCyy3ijxkoA/fakVwh/GgTcMsRt73IY6
 n6DsUvWwuYHCIeIiHmHQJqCqCRtV+aMzU3AbbBHOjtdIanhlW16M686dEsgCirh7
 akRVRD5VqKaqXs34PpkRL89Xv3wZRjl6XZ3hZFfCjSYXfpXDXhgSToIskpHYhKL8
 gpY7WtG9YQP05Xz5HRCx6EluaZVeKe0lZi6fezX7Mi9AygJQO8FfXqP1mHBlEq40
 ThWtvL9D89RV6lADqqFN20XepgvKNOyAXcE4szvsnIZYUSPmZQZSPxx+DHtROaLP
 jX3ifxtxJp92pQ==
 =5g7K
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
   configured SMT state when hotplugging CPUs into the system

 - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
   Radix MMU to avoid a broadcast TLBIE flush on exit

 - Drop the exclusion between ptrace/perf watchpoints, and drop the now
   unused associated arch hooks

 - Add support for the "nohlt" command line option to disable CPU idle

 - Add support for -fpatchable-function-entry for ftrace, with GCC >=
   13.1

 - Rework memory block size determination, and support 256MB size on
   systems with GPUs that have hotpluggable memory

 - Various other small features and fixes

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.

* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
  macintosh/ams: linux/platform_device.h is needed
  powerpc/xmon: Reapply "Relax frame size for clang"
  powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
  powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
  powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
  powerpc/mpc5xxx: Add missing fwnode_handle_put()
  powerpc/config: Disable SLAB_DEBUG_ON in skiroot
  powerpc/pseries: Remove unused hcall tracing instruction
  powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
  powerpc: dts: add missing space before {
  powerpc/eeh: Use pci_dev_id() to simplify the code
  powerpc/64s: Move CPU -mtune options into Kconfig
  powerpc/powermac: Fix unused function warning
  powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
  powerpc: Don't include lppaca.h in paca.h
  powerpc/pseries: Move hcall_vphn() prototype into vphn.h
  powerpc/pseries: Move VPHN constants into vphn.h
  cxl: Drop unused detach_spa()
  powerpc: Drop zalloc_maybe_bootmem()
  powerpc/powernv: Use struct opal_prd_msg in more places
  ...
2023-08-31 12:43:10 -07:00
Linus Torvalds
b6f6167ea8 pci-v6.6-changes
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCgAyFiEEgMe7l+5h9hnxdsnuWYigwDrT+vwFAmTvfQgUHGJoZWxnYWFz
 QGdvb2dsZS5jb20ACgkQWYigwDrT+vyDKA//UBxniXTyxvN8L/agMZngFJd9jLkE
 p2lnk5eTW6y/aJp1g+ujc7IJEmHG/B1Flp0b5mK8XL7S6OBtAGlPwnuPPpXb0ZxV
 ofSuQpYoNZGpkYrQMYvATfdLnH2WF3Yj3WCqh5jd2EldPEyqhMV68l7NMzf6+td2
 KWJPli1XO8e60JAzbhpXH9vn1I0T8e6Qx8z/ulcydfiOH3PGDPnVrEo8gw9CvJOr
 aDqSPW7uhTk2SjjUJcAlQVpTGclE4yBxOOhEbuSGc7L6Ab04Y6D0XKx1589AUK6Z
 W2dQFK3cFYNQQ9aS/2DMUG88H09ca5t8kgUf7Iz3uan1soPzSYK8SLNBgxAPs11S
 1jY093rDXXoaCJqxWUwDc/JUpWq6T3g4m445SNvFIOMcSwmMOIfAwfug4UexE1zC
 Ie8u3Um35Mp25o0o6V1J2EjdBsUsm0p//CsslfoAAIWi85W02Z/46bLLcITchkCe
 bP05H+c55ZN6maRJiaeghcpY+iWO4XCRCKS9mF1v9yn7FOhNxhBcwgTNPyGBVrYz
 T9w3ynTHAmuwNqtd6jhpTR/b1902up/Qv9I8uHhBDMqJAXfHocGEXHZblNuZMgfE
 bu9cjcbFghUPdrhUHYmbEqAzhdlL2SFuMYfn8D4QV4A6x+32xCdwsi39I0Effm5V
 wl0HmemjKjTYbLw=
 =iFFM
 -----END PGP SIGNATURE-----

Merge tag 'pci-v6.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:
   - Add locking to read/modify/write PCIe Capability Register accessors
     for Link Control and Root Control
   - Use pci_dev_id() when possible instead of manually composing ID
     from dev->bus->number and dev->devfn

  Resource management:
   - Move prototypes for __weak sysfs resource files to linux/pci.h to
     fix 'no previous prototype' warnings
   - Make more I/O port accesses depend on HAS_IOPORT
   - Use devm_platform_get_and_ioremap_resource() instead of open-coding
     platform_get_resource() followed by devm_ioremap_resource()

  Power management:
   - Ensure devices are powered up while accessing VPD
   - If device is powered-up, keep it that way while polling for PME
   - Only read PCI_PM_CTRL register when available, to avoid reading the
     wrong register and corrupting dev->current_state

  Virtualization:
   - Avoid Secondary Bus Reset on NVIDIA T4 GPUs

  Error handling:
   - Remove unused pci_disable_pcie_error_reporting()
   - Unexport pci_enable_pcie_error_reporting(), used only by aer.c
   - Unexport pcie_port_bus_type, used only by PCI core

  VGA:
   - Simplify and clean up typos in VGA arbiter

  Apple PCIe controller driver:
   - Initialize pcie->nvecs (number of available MSIs) before use

  Broadcom iProc PCIe controller driver:
   - Use of_property_read_bool() instead of low-level accessors for
     boolean properties

  Broadcom STB PCIe controller driver:
   - Assert PERST# when probing BCM2711 because some bootloaders don't
     do it

  Freescale i.MX6 PCIe controller driver:
   - Add .host_deinit() callback so we can clean up things like
     regulators on probe failure or driver unload

  Freescale Layerscape PCIe controller driver:
   - Add support for link-down notification so the endpoint driver can
     process LINK_DOWN events
   - Add suspend/resume support, including manual
     PME_Turn_off/PME_TO_Ack handshake
   - Save Link Capabilities during probe so they can be restored when
     handling a link-up event, since the controller loses the Link Width
     and Link Speed values during reset

  Intel VMD host bridge driver:
   - Fix disable of bridge windows during domain reset; previously we
     cleared the base/limit registers, which actually left the windows
     enabled

  Marvell MVEBU PCIe controller driver:
   - Remove unused busn member

  Microchip PolarFlare PCIe controller driver:
   - Fix interrupt bit definitions so the SEC and DED interrupt handlers
     work correctly
   - Make driver buildable as a module
   - Read FPGA MSI configuration parameters from hardware instead of
     hard-coding them

  Microsoft Hyper-V host bridge driver:
   - To avoid a NULL pointer dereference, skip MSI restore after
     hibernate if MSI/MSI-X hasn't been enabled

  NVIDIA Tegra194 PCIe controller driver:
   - Revert 'PCI: tegra194: Enable support for 256 Byte payload' because
     Linux doesn't know how to reduce MPS from to 256 to 128 bytes for
     endpoints below a switch (because other devices below the switch
     might already be operating), which leads to 'Malformed TLP' errors

  Qualcomm PCIe controller driver:
   - Add DT and driver support for interconnect bandwidth voting for
     'pcie-mem' and 'cpu-pcie' interconnects
   - Fix broken SDX65 'compatible' DT property
   - Configure controller so MHI bus master clock will be switched off
     while in ASPM L1.x states
   - Use alignment restriction from EPF core in EPF MHI driver
   - Add Endpoint eDMA support
   - Add MHI eDMA support
   - Add Snapdragon SM8450 support to the EPF MHI driversupport
   - Add MHI eDMA support
   - Add Snapdragon SM8450 support to the EPF MHI driversupport
   - Add MHI eDMA support
   - Add Snapdragon SM8450 support to the EPF MHI driversupport
   - Add MHI eDMA support
   - Add Snapdragon SM8450 support to the EPF MHI driver
   - Use iATU for EPF MHI transfers smaller than 4K to avoid eDMA setup
     latency
   - Add sa8775p DT binding and driver support

  Rockchip PCIe controller driver:
   - Use 64-bit mask on MSI 64-bit PCI address to avoid zeroing out the
     upper 32 bits

  SiFive FU740 PCIe controller driver:
   - Set the supported number of MSI vectors so we can use all available
     MSI interrupts

  Synopsys DesignWare PCIe controller driver:
   - Add generic dwc suspend/resume APIs (dw_pcie_suspend_noirq() and
     dw_pcie_resume_noirq()) to be called by controller driver
     suspend/resume ops, and a controller callback to send PME_Turn_Off

  MicroSemi Switchtec management driver:
   - Add support for PCIe Gen5 devices

  Miscellaneous:
   - Reorder and compress to reduce size of struct pci_dev
   - Fix race in DOE destroy_work_on_stack()
   - Add stubs to avoid casts between incompatible function types
   - Explicitly include correct DT includes to untangle headers"

* tag 'pci-v6.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (96 commits)
  PCI: qcom-ep: Add ICC bandwidth voting support
  dt-bindings: PCI: qcom: ep: Add interconnects path
  PCI: qcom-ep: Treat unknown IRQ events as an error
  dt-bindings: PCI: qcom: Fix SDX65 compatible
  PCI: endpoint: Add kernel-doc for pci_epc_mem_init() API
  PCI: epf-mhi: Use iATU for small transfers
  PCI: epf-mhi: Add support for SM8450
  PCI: epf-mhi: Add eDMA support
  PCI: qcom-ep: Add eDMA support
  PCI: epf-mhi: Make use of the alignment restriction from EPF core
  PCI/PM: Only read PCI_PM_CTRL register when available
  PCI: qcom: Add support for sa8775p SoC
  dt-bindings: PCI: qcom: Add sa8775p compatible
  PCI: qcom-ep: Pass alignment restriction to the EPF core
  PCI: Simplify pcie_capability_clear_and_set_word() control flow
  PCI: Tidy config space save/restore messages
  PCI: Fix code formatting inconsistencies
  PCI: Fix typos in docs and comments
  PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos
  PCI: Simplify pci_dev_driver()
  ...
2023-08-30 20:23:07 -07:00
Bjorn Helgaas
43cc31da91 Merge branch 'pci/misc'
- Reorder struct pci_dev to avoid holes and reduce size (Christophe
  JAILLET)

- Change pdev->rom_attr_enabled to single bit since it's only a boolean
  value (Christophe JAILLET)

- Use struct_size() in pirq_convert_irt_table() instead of hand-writing it
  (Christophe JAILLET)

- Explicitly include correct DT includes to untangle headers (Rob Herring)

- Fix a DOE race between destroy_work_on_stack() and the stack-allocated
  task->work struct going out of scope in pci_doe() (Ira Weiny)

- Use pci_dev_id() when possible instead of manually composing ID from
  dev->bus->number and dev->devfn (Xiongfeng Wang, Zheng Zengkai)

- Move pci_create_resource_files() declarations to linux/pci.h for alpha
  build warnings (Arnd Bergmann)

- Remove unused hotplug function declarations (Yue Haibing)

- Remove unused mvebu struct mvebu_pcie.busn (Pali Rohár)

- Unexport pcie_port_bus_type (Bjorn Helgaas)

- Remove unnecessary sysfs ID local variable initialization (Bjorn Helgaas)

- Fix BAR value printk formatting to accommodate 32-bit values (Bjorn
  Helgaas)

- Use consistent pointer types for config access syscall get_user() and
  put_user() uses (Bjorn Helgaas)

- Simplify AER_RECOVER_RING_SIZE definition (Bjorn Helgaas)

- Simplify pci_pio_to_address() (Bjorn Helgaas)

- Simplify pci_dev_driver() (Bjorn Helgaas)

- Fix pci_bus_resetable(), pci_slot_resetable() name typos (Bjorn Helgaas)

- Fix code and doc typos and code formatting (Bjorn Helgaas)

- Tidy config space save/restore messages (Bjorn Helgaas)

* pci/misc:
  PCI: Tidy config space save/restore messages
  PCI: Fix code formatting inconsistencies
  PCI: Fix typos in docs and comments
  PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos
  PCI: Simplify pci_dev_driver()
  PCI: Simplify pci_pio_to_address()
  PCI/AER: Simplify AER_RECOVER_RING_SIZE definition
  PCI: Use consistent put_user() pointer types
  PCI: Fix printk field formatting
  PCI: Remove unnecessary initializations
  PCI: Unexport pcie_port_bus_type
  PCI: mvebu: Remove unused busn member
  PCI: Remove unused function declarations
  PCI/sysfs: Move declarations to linux/pci.h
  PCI/P2PDMA: Use pci_dev_id() to simplify the code
  PCI/IOV: Use pci_dev_id() to simplify the code
  PCI/AER: Use pci_dev_id() to simplify the code
  PCI: apple: Use pci_dev_id() to simplify the code
  PCI/DOE: Fix destroy_work_on_stack() race
  PCI: Explicitly include correct DT includes
  x86/PCI: Use struct_size() in pirq_convert_irt_table()
  PCI: Change pdev->rom_attr_enabled to single bit
  PCI: Reorder pci_dev fields to reduce holes
2023-08-29 11:03:57 -05:00
Bjorn Helgaas
8b524514e4 Merge branch 'pci/pcie-rmw'
- Add locking for read/modify/write PCIe Capability Register accessors for
  Link Control and Root Control (Ilpo Järvinen)

- Use PCIe RMW accessors for Link Control updates in PCI core, pciehp,
  amdgpu, radeon, mlx5, ath10k, ath11k, ath12k (Ilpo Järvinen)

- Convert PCIBIOS error values in mlx5 to generic errnos (Ilpo Järvinen)

- Simplify pcie_capability_clear_and_set_word() control flow (Bjorn
  Helgaas)

* pci/pcie-rmw:
  PCI: Simplify pcie_capability_clear_and_set_word() control flow
  net/mlx5: Convert PCI error values to generic errnos
  PCI: Document the Capability accessor RMW improvements
  wifi: ath10k: Use RMW accessors for changing LNKCTL
  wifi: ath12k: Use RMW accessors for changing LNKCTL
  wifi: ath11k: Use RMW accessors for changing LNKCTL
  net/mlx5: Use RMW accessors for changing LNKCTL
  drm/radeon: Use RMW accessors for changing LNKCTL
  drm/amdgpu: Use RMW accessors for changing LNKCTL
  PCI/ASPM: Use RMW accessors for changing LNKCTL
  PCI: pciehp: Use RMW accessors for changing LNKCTL
  PCI: Make link retraining use RMW accessors for changing LNKCTL
  PCI: Add locking to RMW PCI Express Capability Register accessors
2023-08-29 11:03:49 -05:00
Yue Haibing
ea91512ded PCI: Remove unused function declarations
The following declarations have never been implemented since the beginning
of git history, so remove them:

  u8 acpiphp_get_attention_status(struct acpiphp_slot *slot);
  u8 cpci_get_latch_status(struct slot *slot);
  u8 cpci_get_adapter_status(struct slot *slot);
  int ibmphp_get_total_hp_slots(void);
  void ibmphp_free_ibm_slot(struct slot *);
  void pdev_enable_device(struct pci_dev *);

Link: https://lore.kernel.org/r/20230811095933.28652-1-yuehaibing@huawei.com
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-08-24 15:38:59 -05:00
Mahesh Salgaonkar
77583f77ed PCI: rpaphp: Error out on busy status from get-sensor-state
When certain PHB HW failure causes pHyp to recover PHB, it marks the PE
state as temporarily unavailable until recovery is complete. This also
triggers an EEH handler in Linux which needs to notify drivers, and perform
recovery. But before notifying the driver about the PCI error it uses
get_adapter_status()->rpaphp_get_sensor_state()->rtas_call(get-sensor-state)
operation of the hotplug_slot to determine if the slot contains a device or
not. If the slot is empty, the recovery is skipped entirely.

eeh_event_handler()
  ->eeh_handle_normal_event()
    ->eeh_slot_presence_check()
      ->get_adapter_status()
        ->rpaphp_get_sensor_state()
          ->rtas_get_sensor()
            ->rtas_call(get-sensor-state)

However on certain PHB failures, the RTAS call rtas_call(get-sensor-state)
returns extended busy error (9902) until PHB is recovered by pHyp. Once PHB
is recovered, the rtas_call(get-sensor-state) returns success with correct
presence status. The RTAS call interface rtas_get_sensor() loops over the
RTAS call on extended delay return code (9902) until the return value is
either success (0) or error (-1). This causes the EEH handler to get stuck
for ~6 seconds before it could notify that the PCI error has been detected
and stop any active operations. Hence with running I/O traffic, during this
6 seconds, the network driver continues its operation and hits a timeout
(netdev watchdog).

------------
[52732.244731] DEBUG: ibm_read_slot_reset_state2()
[52732.244762] DEBUG: ret = 0, rets[0]=5, rets[1]=1, rets[2]=4000, rets[3]=>
[52732.244798] DEBUG: in eeh_slot_presence_check
[52732.244804] DEBUG: error state check
[52732.244807] DEBUG: Is slot hotpluggable
[52732.244810] DEBUG: hotpluggable ops ?
[52732.244953] DEBUG: Calling ops->get_adapter_status
[52732.244958] DEBUG: calling rpaphp_get_sensor_state
[52736.564262] ------------[ cut here ]------------
[52736.564299] NETDEV WATCHDOG: enP64p1s0f3 (tg3): transmit queue 0 timed o>
[52736.564324] WARNING: CPU: 1442 PID: 0 at net/sched/sch_generic.c:478 dev>
[...]
[52736.564505] NIP [c000000000c32368] dev_watchdog+0x438/0x440
[52736.564513] LR [c000000000c32364] dev_watchdog+0x434/0x440
------------

On timeouts, network driver starts dumping debug information to console
(e.g bnx2 driver calls bnx2x_panic_dump()), and go into recovery path while
pHyp is still recovering the PHB. As part of recovery, the driver tries to
reset the device and it keeps failing since every PCI read/write returns
ff's. And when EEH recovery kicks-in, the driver is unable to recover the
device. This impacts the ssh connection and leads to the system being
inaccessible. To get the NIC working again it needs a reboot or re-assign
the I/O adapter from HMC.

[ 9531.168587] EEH: Beginning: 'slot_reset'
[ 9531.168601] PCI 0013:01:00.0#10000: EEH: Invoking bnx2x->slot_reset()
[...]
[ 9614.110094] bnx2x: [bnx2x_func_stop:9129(enP19p1s0f0)]FUNC_STOP ramrod failed. Running a dry transaction
[ 9614.110300] bnx2x: [bnx2x_igu_int_disable:902(enP19p1s0f0)]BUG! Proper val not read from IGU!
[ 9629.178067] bnx2x: [bnx2x_fw_command:3055(enP19p1s0f0)]FW failed to respond!
[ 9629.178085] bnx2x 0013:01:00.0 enP19p1s0f0: bc 7.10.4
[ 9629.178091] bnx2x: [bnx2x_fw_dump_lvl:789(enP19p1s0f0)]Cannot dump MCP info while in PCI error
[ 9644.241813] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f0)]IO slot reset --> driver unload
[...]
[ 9644.241819] PCI 0013:01:00.0#10000: EEH: bnx2x driver reports: 'disconnect'
[ 9644.241823] PCI 0013:01:00.1#10000: EEH: Invoking bnx2x->slot_reset()
[ 9644.241827] bnx2x: [bnx2x_io_slot_reset:14229(enP19p1s0f1)]IO slot reset initializing...
[ 9644.241916] bnx2x 0013:01:00.1: enabling device (0140 -> 0142)
[ 9644.258604] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f1)]IO slot reset --> driver unload
[ 9644.258612] PCI 0013:01:00.1#10000: EEH: bnx2x driver reports: 'disconnect'
[ 9644.258615] EEH: Finished:'slot_reset' with aggregate recovery state:'disconnect'
[ 9644.258620] EEH: Unable to recover from failure from PHB#13-PE#10000.
[ 9644.261811] EEH: Beginning: 'error_detected(permanent failure)'
[...]
[ 9644.261823] EEH: Finished:'error_detected(permanent failure)'

Hence, it becomes important to inform driver about the PCI error detection
as early as possible, so that driver is aware of PCI error and waits for
EEH handler's next action for successful recovery.

Current implementation uses rtas_get_sensor() API which blocks the slot
check state until RTAS call returns success. To avoid this, fix the PCI
hotplug driver (rpaphp) to return an error (-EBUSY) if the slot presence
state can not be detected immediately while PE is in EEH recovery state.
Change rpaphp_get_sensor_state() to invoke rtas_call(get-sensor-state)
directly only if the respective PE is in EEH recovery state, and take
actions based on RTAS return status. This way EEH handler will not be
blocked on rpaphp_get_sensor_state() and can immediately notify driver
about the PCI error and stop any active operations.

In normal cases (non-EEH case) rpaphp_get_sensor_state() will continue to
invoke rtas_get_sensor() as it was earlier with no change in existing
behavior.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/169235815601.193557.13989873835811325343.stgit@jupiter
2023-08-18 23:30:22 +10:00
Ilpo Järvinen
5f75f96c61 PCI: pciehp: Use RMW accessors for changing LNKCTL
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>
2023-08-10 11:13:34 -05:00
Igor Mammedov
cc22522fd5 PCI: acpiphp: Use pci_assign_unassigned_bridge_resources() only for non-root bus
40613da52b ("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
40613da52b 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 40613da52b.

Fixes: 40613da52b ("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>
2023-08-08 14:30:00 -05:00
Colin Ian King
5810ab2186 PCI: ibmphp: Make read-only arrays static
Don't populate the arrays on the stack; instead make them static const.

Link: https://lore.kernel.org/r/20230627125612.724764-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-07-18 16:52:41 -05:00
Bjorn Helgaas
db5ccb2eda Merge branch 'pci/hotplug'
- Simplify Attention Button logging (Bjorn Helgaas)

- Cancel bringup sequence if card is not present, to keep from blinking
  Power Indicator indefinitely (Rongguang Wei)

- Reassign bridge resources if necessary for ACPI hotplug (Igor Mammedov)

* pci/hotplug:
  PCI: acpiphp: Reassign resources on bridge if necessary
  PCI: pciehp: Cancel bringup sequence if card is not present
  PCI: pciehp: Simplify Attention Button logging
2023-06-26 12:59:56 -05:00
Maciej W. Rozycki
1f087398db PCI: pciehp: Rely on dev->link_active_reporting
Use dev->link_active_reporting to determine whether Data Link Layer Link
Active Reporting is available rather than re-retrieving the capability.

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310028150.59226@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2023-06-14 17:58:12 -05:00
Igor Mammedov
40613da52b PCI: acpiphp: Reassign resources on bridge if necessary
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
2023-05-24 11:53:41 -05:00
Rongguang Wei
e8afd0d9fc PCI: pciehp: Cancel bringup sequence if card is not present
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>
2023-05-24 11:52:38 -05:00
Bjorn Helgaas
5054133a88 PCI: pciehp: Simplify Attention Button logging
Previously, pressing the Attention Button always logged two lines, the
first from pciehp_ist() and the second from pciehp_handle_button_press():

  Attention button pressed
  Powering on due to button press

Since pciehp_handle_button_press() always logs the more detailed message,
remove the generic "Attention button pressed" message.  Reword the
pciehp_handle_button_press() to be of the form:

  Button press: will power on in 5 sec
  Button press: will power off in 5 sec
  Button press: canceling request to power on
  Button press: canceling request to power off
  Button press: ignoring invalid state %#x

Link: https://lore.kernel.org/r/20230522214051.619337-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2023-05-24 11:49:50 -05:00
Bjorn Helgaas
1c03b5bfc5 Merge branch 'pci/resource'
- Add pci_dev_for_each_resource() and pci_bus_for_each_resource() iterators
  to simplify loops (Andy Shevchenko)

* pci/resource:
  EISA: Drop unused pci_bus_for_each_resource() index argument
  PCI: Make pci_bus_for_each_resource() index optional
  PCI: Document pci_bus_for_each_resource()
  PCI: Introduce pci_dev_for_each_resource()
  PCI: Introduce pci_resource_n()
2023-04-20 16:16:34 -05:00
Bjorn Helgaas
8745c3d542 Merge branch 'pci/hotplug'
- Fix pciehp AB-BA deadlock between reset_lock and device_lock (Lukas
  Wunner)

* pci/hotplug:
  PCI: pciehp: Fix AB-BA deadlock between reset_lock and device_lock
2023-04-20 16:16:33 -05:00
Rob Herring
9195ee1a1f PCI: Use of_property_present() for testing DT property presence
It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property()/of_find_property() functions for reading properties. As
part of this, convert of_get_property()/of_find_property() calls to the
recently added of_property_present() helper when we just want to test for
presence of a property and nothing more.

Link: https://lore.kernel.org/r/20230310144719.1544443-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>  # pcie-mediatek
2023-04-18 16:01:37 -05:00
Lukas Wunner
f5eff5591b PCI: pciehp: Fix AB-BA deadlock between reset_lock and device_lock
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>
2023-04-11 13:18:30 -05:00
Andy Shevchenko
02992064bd PCI: Make pci_bus_for_each_resource() index optional
Refactor pci_bus_for_each_resource() in the same way as
pci_dev_for_each_resource(). This allows the index to be hidden inside the
implementation so the caller can omit it when it's not used otherwise.

No functional changes intended.

Link: https://lore.kernel.org/r/20230330162434.35055-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-04-05 15:10:09 -05:00
Bjorn Helgaas
881766fe0d Merge branch 'pci/kbuild'
- Remove MODULE_LICENSE from boolean drivers so they don't look like
  modules so modprobe will complain about them (Nick Alcock)

* pci/kbuild:
  PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules
2023-02-22 13:47:25 -06:00
Nick Alcock
f98954b293 PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules
Since 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are
used to identify modules. As a consequence, MODULE_LICENSE in non-modules
causes modprobe to misidentify the object file as a module when it is not,
and modprobe might succeed rather than failing with a suitable error
message.

For tristate modules that can be either built-in or loaded at runtime,
modprobe succeeds in both cases:

  # modprobe ext4
  [exit status zero if CONFIG_EXT4_FS=y or =m]

For boolean modules like the Standard Hot Plug Controller driver (shpchp)
that cannot be loaded at runtime, modprobe should always fail like this:

  # modprobe shpchp
  modprobe: FATAL: Module shpchp not found in directory /lib/modules/...
  [exit status non-zero regardless of CONFIG_HOTPLUG_PCI_SHPC]

but prior to this commit, shpchp_core.c contained MODULE_LICENSE, so
"modprobe shpchp" silently succeeded when it should have failed.

Remove MODULE_LICENSE in files that cannot be built as modules.

[bhelgaas: commit log, squash]
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230216152410.4312-1-nick.alcock@oracle.com/
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
2023-02-17 08:47:58 -06:00
Manivannan Sadhasivam
82b34b0800 PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
The Qualcomm PCI bridge device (Device ID 0x010e) found in chipsets such as
SC8280XP used in Lenovo Thinkpad X13s, does not set the Command Completed
bit unless writes to the Slot Command register change "Control" bits.

This results in timeouts like below during boot and resume from suspend:

  pcieport 0002:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2020 msec ago)
  ...
  pcieport 0002:00:00.0: pciehp: Timeout on hotplug command 0x13f1 (issued 107724 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/20230213144922.89982-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-02-14 11:47:49 -06:00
Pali Rohár
6d4671b534 PCI: pciehp: Enable Command Completed Interrupt only if supported
The No Command Completed Support bit in the Slot Capabilities register
indicates whether Command Completed Interrupt Enable is unsupported.

We already check whether No Command Completed Support bit is set in
pcie_wait_cmd(), and do not wait in this case.

Don't enable this Command Completed Interrupt at all if NCCS is set, so
that when users dump configuration space from userspace, the dump does not
confuse them by saying that Command Completed Interrupt is not supported,
but it is enabled.

Link: https://lore.kernel.org/r/20220927141926.8895-2-kabel@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2022-12-07 08:27:20 -06:00
Ian Cowan
9676f40618 PCI: shpchp: Remove unused get_mode1_ECC_cap callback
The ->get_mode1_ECC_cap callback in the shpchp_hpc_ops struct is never
called, so remove it.

[bhelgaas: squash]
Link: https://lore.kernel.org/r/20221112142859.319733-2-ian@linux.cowan.aero
Link: https://lore.kernel.org/r/20221112142859.319733-3-ian@linux.cowan.aero
Link: https://lore.kernel.org/r/20221112142859.319733-4-ian@linux.cowan.aero
Signed-off-by: Ian Cowan <ian@linux.cowan.aero>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-11-22 14:09:51 -06:00
Rafael J. Wysocki
c63a3be76d PCI: acpiphp: Avoid setting is_hotplug_bridge for PCIe Upstream Ports
It is reported that on some systems pciehp binds to an Upstream Port and
attempts to operate it which causes devices below the Port to disappear
from the bus.

This happens because acpiphp sets dev->is_hotplug_bridge for that Port
(after receiving a Device Check notification on it from the platform
firmware via ACPI) during the enumeration of PCI devices.

get_port_device_capability() sees that dev->is_hotplug_bridge is set and
adds PCIE_PORT_SERVICE_HP to Port services, which allows pciehp to bind to
the Port in question.

Even though this particular problem can be addressed by making the
portdrv_core checks more robust, it also causes power management to work
differently on the affected systems which generally is not desirable (PCIe
Ports with dev->is_hotplug_bridge set have to pass additional tests to be
allowed to go into the D3hot/cold power states which affects runtime PM of
devices below these Ports).

For this reason, amend check_hotplug_bridge() with a PCIe type check to
prevent it from setting dev->is_hotplug_bridge for Upstream Ports.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/2262230.ElGaqSPkdT@kreacher
Reported-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Tested-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2022-11-22 13:27:28 -06:00
Albert Zhou
e67ad9354a PCI: pciehp: Enable by default if USB4 enabled
Thunderbolt/USB4 PCIe tunneling depends on native PCIe hotplug.  Enable
pciehp by default if USB4 is enabled.

[bhelgaas: squash, update subject, commit logs, tidy whitespace]
Link: https://lore.kernel.org/r/20221115113857.35800-2-albert.zhou.50@gmail.com
Link: https://lore.kernel.org/r/20221115113857.35800-3-albert.zhou.50@gmail.com
Signed-off-by: Albert Zhou <albert.zhou.50@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-11-15 09:25:21 -06:00
Christophe Leroy
b2851926c6 PCI: hotplug: Clean up include files
arch/powerpc/include/asm/prom.h includes some headers that it doesn't need
itself.  Add the missing headers to files that include prom.h so we can
remove them from prom.h.

Link: https://lore.kernel.org/r/79201f5fae8d003164ac36ed3be7789db1bc5ab4.1648833421.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-04-05 11:13:33 -05:00
Linus Torvalds
148a650476 pci-v5.18-changes
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCgAyFiEEgMe7l+5h9hnxdsnuWYigwDrT+vwFAmI7iOwUHGJoZWxnYWFz
 QGdvb2dsZS5jb20ACgkQWYigwDrT+vxkuhAAtJkVwfeyUjZ8sms+qWdZaucJmFF1
 PDeKy8O8upLzRRykdWoAOjKKVcCB9ohxBjPMco2oYNTmSozxeau8jjMA9OTQvTOS
 ZhDDoi49/vHRHuq3WIeAMCuk7tH3H1L3f0UHJxJ3H/oObQ+eMsitPcGFK+QrISDX
 pYokOnXZvf7BT7NpVtogSe2mhniOD1zQSicAMiH6WKNHHZcxewrzV9LP3MFOoBAr
 VMhlhzJbOp9spvCt7M1DycJEQ2RNe+wGLBFDalhPuprwnkNchRV+0AwWfD90zc9u
 h/0J8jkXfqS6QfSd/lOlTvI6kGsV8UKZEt4h4X/hlHFebFM5ktD9X7GmcoYUDFd9
 aHV3I/Jf62uGJ31IrT0V/cSYNlMO+IVFwXLGir4B1cFPOkzyIG/i60iV/C6bnnCa
 TCMH6vxalFycYaHBFqw/K/Dlq+mrAX74nQDfbk8y6rprczM1BN220Z8BkpG13TBu
 MxgCEul2/BJmNcPS1IWb/mCfBy+rdrVn2DZuID3J9KTwKNOUTIuAF0FuxLP4Bk4o
 sti3vKIXOcHnAcJB9tEnpEfstPv2JT13eWDIMmp/qCwqcujOvsg/DSYrx+8ogmBF
 DJ/sbPy3BdIOAeTgepWHAxYcv9SlZTGJGl+oaR1zV0qLBogyQUWZ9Ijx5aAEAw3j
 AJicpdk3BkH3LC8=
 =5Q9H
 -----END PGP SIGNATURE-----

Merge tag 'pci-v5.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:
   - Move the VGA arbiter from drivers/gpu to drivers/pci because it's
     PCI-specific, not GPU-specific (Bjorn Helgaas)
   - Select the default VGA device consistently whether it's enumerated
     before or after VGA arbiter init, which fixes arches that enumerate
     PCI devices late (Huacai Chen)

  Resource management:
   - Support BAR sizes up to 8TB (Dongdong Liu)

  PCIe native device hotplug:
   - Fix "Command Completed" tracking to avoid spurious timouts when
     powering off empty slots (Liguang Zhang)
   - Quirk Qualcomm devices that don't implement Command Completed
     correctly, again to avoid spurious timeouts (Manivannan Sadhasivam)

  Peer-to-peer DMA:
   - Add Intel 3rd Gen Intel Xeon Scalable Processors to whitelist
     (Michael J. Ruhl)

  APM X-Gene PCIe controller driver:
   - Revert generic DT parsing changes that broke some machines in the
     field (Marc Zyngier)

  Freescale i.MX6 PCIe controller driver:
   - Allow controller probe to succeed even when no devices currently
     present to allow hot-add later (Fabio Estevam)
   - Enable power management on i.MX6QP (Richard Zhu)
   - Assert CLKREQ# on i.MX8MM so enumeration doesn't hang when no
     device is connected (Richard Zhu)

  Marvell Aardvark PCIe controller driver:
   - Fix MSI and MSI-X support (Marek Behún, Pali Rohár)
   - Add support for ERR and PME interrupts (Pali Rohár)

  Marvell MVEBU PCIe controller driver:
   - Add DT binding and support for "num-lanes" (Pali Rohár)
   - Add support for INTx interrupts (Pali Rohár)

  Microsoft Hyper-V host bridge driver:
   - Avoid unnecessary hypercalls when unmasking IRQs on ARM64 (Boqun
     Feng)

  Qualcomm PCIe controller driver:
   - Add SM8450 DT binding and driver support (Dmitry Baryshkov)

  Renesas R-Car PCIe controller driver:
   - Help the controller get to the L1 state since the hardware can't do
     it on its own (Marek Vasut)
   - Return PCI_ERROR_RESPONSE (~0) for reads that fail on PCIe (Marek
     Vasut)

  SiFive FU740 PCIe controller driver:
   - Drop redundant '-gpios' from DT GPIO lookup (Ben Dooks)
   - Force 2.5GT/s for initial device probe (Ben Dooks)

  Socionext UniPhier Pro5 controller driver:
   - Add NX1 DT binding and driver support (Kunihiko Hayashi)

  Synopsys DesignWare PCIe controller driver:
   - Restore MSI configuration so MSI works after resume (Jisheng
     Zhang)"

* tag 'pci-v5.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
  x86/PCI: Add #includes to asm/pci_x86.h
  PCI: ibmphp: Remove unused assignments
  PCI: cpqphp: Remove unused assignments
  PCI: fu740: Remove unused assignments
  PCI: kirin: Remove unused assignments
  PCI: Remove unused assignments
  PCI: Declare pci_filp_private only when HAVE_PCI_MMAP
  PCI: Avoid broken MSI on SB600 USB devices
  PCI: fu740: Force 2.5GT/s for initial device probe
  PCI: xgene: Revert "PCI: xgene: Fix IB window setup"
  PCI: xgene: Revert "PCI: xgene: Use inbound resources for setup"
  PCI: imx6: Assert i.MX8MM CLKREQ# even if no device present
  PCI: imx6: Invoke the PHY exit function after PHY power off
  PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception
  PCI: rcar: Finish transition to L1 state in rcar_pcie_config_access()
  PCI: dwc: Restore MSI Receiver mask during resume
  PCI: fu740: Drop redundant '-gpios' from DT GPIO lookup
  PCI/VGA: Replace full MIT license text with SPDX identifier
  PCI/VGA: Use unsigned format string to print lock counts
  PCI/VGA: Log bridge control messages when adding devices
  ...
2022-03-25 13:02:05 -07:00
Bjorn Helgaas
73c82469bd Merge branch 'pci/misc'
- Update the aer-inject URL (Yicong Yang)

- Declare pci_filp_private only when HAVE_PCI_MMAP to avoid unused struct
  definition (Krzysztof Wilczyński)

- Remove unused assignments (Bjorn Helgaas)

- Add #includes to asm/pci_x86.h to prevent build errors (Randy Dunlap)

* pci/misc:
  x86/PCI: Add #includes to asm/pci_x86.h
  PCI: ibmphp: Remove unused assignments
  PCI: cpqphp: Remove unused assignments
  PCI: fu740: Remove unused assignments
  PCI: kirin: Remove unused assignments
  PCI: Remove unused assignments
  PCI: Declare pci_filp_private only when HAVE_PCI_MMAP
  PCI/AER: Update aer-inject URL
2022-03-22 17:16:21 -05:00
Bjorn Helgaas
f787b68214 Merge branch 'pci/hotplug'
- Clear pciehp cmd_busy bit when command completes in polling mode to avoid
  spurious timeouts (Liguang Zhang)

- Add quirk to work around Qualcomm hardware defect in Command Completed
  signaling (Manivannan Sadhasivam)

* pci/hotplug:
  PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
  PCI: pciehp: Clear cmd_busy bit in polling mode
2022-03-22 17:16:20 -05:00
Bjorn Helgaas
fde14ee629 Merge branch 'pci/bridge-class-codes'
- Add and use #defines for normal and subtractive PCI bridges (Pali Rohár)

- Set all 24 bits of PCI class code for iproc (Pali Rohár)

* pci/bridge-class-codes:
  PCI: iproc: Set all 24 bits of PCI class code
  PCI: Add defines for normal and subtractive PCI bridges
2022-03-22 17:16:20 -05:00
Bjorn Helgaas
6a8fcf7d47 PCI: ibmphp: Remove unused assignments
Remove variables and assignments that are never used.

Found by Krzysztof using cppcheck, e.g.:

  $ cppcheck --enable=all --force
  unreadVariable drivers/pci/hotplug/ibmphp_res.c:1958 Variable 'bus_sec' is assigned a value that is never used.

Reported-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20220313192933.434746-6-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-03-22 11:24:48 -05:00
Bjorn Helgaas
af8b8b6c04 PCI: cpqphp: Remove unused assignments
Remove variables and assignments that are never used.

Found by Krzysztof using cppcheck, e.g.:

  $ cppcheck --enable=all --force
  unreadVariable drivers/pci/hotplug/cpqphp_core.c:1257 Variable 'rc' is assigned a value that is never used.

Reported-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20220313192933.434746-5-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-03-22 11:24:40 -05:00
Pali Rohár
904b10fb18 PCI: Add defines for normal and subtractive PCI bridges
Add these PCI class codes to pci_ids.h:

  PCI_CLASS_BRIDGE_PCI_NORMAL
  PCI_CLASS_BRIDGE_PCI_SUBTRACTIVE

Use these defines in all kernel code for describing PCI class codes for
normal and subtractive PCI bridges.

[bhelgaas: similar change in pci-mvebu.c]
Link: https://lore.kernel.org/r/20220214114109.26809-1-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-02-17 15:29:35 -06:00
Manivannan Sadhasivam
9f72d4757c PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
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>
2022-02-10 16:43:45 -06:00
Rafael J. Wysocki
9a607a54a1 PCI/ACPI: Replace acpi_bus_get_device() with acpi_fetch_acpi_dev()
Replace acpi_bus_get_device() that is going to be dropped with
acpi_fetch_acpi_dev().

No intentional functional impact.

Link: https://lore.kernel.org/r/11930209.O9o76ZdvQC@kreacher
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-02-04 17:10:44 -06:00
Liguang Zhang
92912b1751 PCI: pciehp: Clear cmd_busy bit in polling mode
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+
2022-02-03 13:36:23 -06:00
Mamatha Inamdar
be7be1c6c6 PCI: rpaphp: Add MODULE_DESCRIPTION
This patch adds a brief MODULE_DESCRIPTION to rpadlpar_io kernel modules
(descriptions taken from Kconfig file).

Signed-off-by: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200924051343.16052.9571.stgit@localhost.localdomain
2022-02-03 21:45:45 +11:00
Bjorn Helgaas
f5d3ca6fff Merge branch 'pci/errors'
- Add PCI_ERROR_RESPONSE and related definitions for signaling and checking
  for transaction errors on PCI (Naveen Naidu)

- Fabricate PCI_ERROR_RESPONSE data (~0) in config read wrappers, instead
  of in host controller drivers, when transactions fail on PCI (Naveen
  Naidu)

- Use PCI_POSSIBLE_ERROR() to check for possible failure of config reads
  (Naveen Naidu)

* pci/errors:
  PCI: xgene: Use PCI_ERROR_RESPONSE to identify config read errors
  PCI: hv: Use PCI_ERROR_RESPONSE to identify config read errors
  PCI: keystone: Use PCI_ERROR_RESPONSE to identify config read errors
  PCI: Use PCI_ERROR_RESPONSE to identify config read errors
  PCI: cpqphp: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI/PME: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI/DPC: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI: pciehp: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI: vmd: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI/ERR: Use PCI_POSSIBLE_ERROR() to check config reads
  PCI: rockchip-host: Drop error data fabrication when config read fails
  PCI: rcar-host: Drop error data fabrication when config read fails
  PCI: altera: Drop error data fabrication when config read fails
  PCI: mvebu: Drop error data fabrication when config read fails
  PCI: aardvark: Drop error data fabrication when config read fails
  PCI: kirin: Drop error data fabrication when config read fails
  PCI: histb: Drop error data fabrication when config read fails
  PCI: exynos: Drop error data fabrication when config read fails
  PCI: mediatek: Drop error data fabrication when config read fails
  PCI: iproc: Drop error data fabrication when config read fails
  PCI: thunder: Drop error data fabrication when config read fails
  PCI: Drop error data fabrication when config read fails
  PCI: Use PCI_SET_ERROR_RESPONSE() for disconnected devices
  PCI: Set error response data when config read fails
  PCI: Add PCI_ERROR_RESPONSE and related definitions
2022-01-13 09:57:52 -06:00
Hans de Goede
085a9f4343 PCI: pciehp: Use down_read/write_nested(reset_lock) to fix lockdep errors
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
2022-01-12 06:42:51 -06:00
Vihas Mak
e1a6333e7f PCI: ibmphp: Remove commented-out functions
The functions get_max_adapter_speed() and get_bus_name() in ibmphp_core.c
are commented-out and the fields .get_max_adapter_speed and
.get_bus_name_status are removed from struct hotplug_slot_ops in
pci_hotplug.h. Remove the commented-out functions.

Link: https://lore.kernel.org/r/20211209213618.20522-1-makvihas@gmail.com
Signed-off-by: Vihas Mak <makvihas@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2021-12-10 09:55:47 -06:00
Lukas Wunner
23584c1ed3 PCI: pciehp: Fix infinite loop in IRQ handler upon power fault
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>
2021-11-19 12:39:33 -06:00