linux.git/drivers/pci/devres.c, branch v6.12.80

PCI: Fix wrong length of devres array

2025-04-20T08:15:58+00:00

commit f09d3937d400433080d17982bd1a540da53a156d upstream.

The array for the iomapping cookie addresses has a length of
PCI_STD_NUM_BARS. This constant, however, only describes standard BARs;
while PCI can allow for additional, special BARs.

The total number of PCI resources is described by constant
PCI_NUM_RESOURCES, which is also used in, e.g., pci_select_bars().

Thus, the devres array has so far been too small.

Change the length of the devres array to PCI_NUM_RESOURCES.

Link: https://lore.kernel.org/r/20250312080634.13731-3-phasta@kernel.org
Fixes: bbaff68bf4a4 ("PCI: Add managed partial-BAR request and map infrastructure")
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Krzysztof Wilczyński 
Cc: stable@vger.kernel.org	# v6.11+
Signed-off-by: Greg Kroah-Hartman

PCI: Check BAR index for validity

2025-04-20T08:15:26+00:00

[ Upstream commit b1a7f99967fc0c052db8e65b449c7b32b1e9177f ]

Many functions in PCI use accessor macros such as pci_resource_len(),
which take a BAR index. That index, however, is never checked for
validity, potentially resulting in undefined behavior by overflowing the
array pci_dev.resource in the macro pci_resource_n().

Since many users of those macros directly assign the accessed value to
an unsigned integer, the macros cannot be changed easily anymore to
return -EINVAL for invalid indexes. Consequently, the problem has to be
mitigated in higher layers.

Add pci_bar_index_valid(). Use it where appropriate.

Link: https://lore.kernel.org/r/20250312080634.13731-4-phasta@kernel.org
Closes: https://lore.kernel.org/all/adb53b1f-29e1-3d14-0e61-351fd2d3ff0d@linux.intel.com/
Reported-by: Bingbu Cao 
Signed-off-by: Philipp Stanner 
[kwilczynski: correct if-statement condition the pci_bar_index_is_valid()
helper function uses, tidy up code comments]
Signed-off-by: Krzysztof Wilczyński 
[bhelgaas: fix typo]
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin

PCI: Restore original INTX_DISABLE bit by pcim_intx()

2025-02-27T12:30:15+00:00

[ Upstream commit d555ed45a5a10a813528c7685f432369d536ae3d ]

pcim_intx() tries to restore the INTx bit at removal via devres, but there
is a chance that it restores a wrong value.

Because the value to be restored is blindly assumed to be the negative of
the enable argument, when a driver calls pcim_intx() unnecessarily for the
already enabled state, it'll restore to the disabled state in turn.  That
is, the function assumes the case like:

  // INTx == 1
  pcim_intx(pdev, 0); // old INTx value assumed to be 1 -> correct

but it might be like the following, too:

  // INTx == 0
  pcim_intx(pdev, 0); // old INTx value assumed to be 1 -> wrong

Also, when a driver calls pcim_intx() multiple times with different enable
argument values, the last one will win no matter what value it is.  This
can lead to inconsistency, e.g.

  // INTx == 1
  pcim_intx(pdev, 0); // OK
  ...
  pcim_intx(pdev, 1); // now old INTx wrongly assumed to be 0

This patch addresses those inconsistencies by saving the original INTx
state at the first pcim_intx() call.  For that, get_or_create_intx_devres()
is folded into pcim_intx() caller side; it allows us to simply check the
already allocated devres and record the original INTx along with the
devres_alloc() call.

Link: https://lore.kernel.org/r/20241031134300.10296-1-tiwai@suse.de
Fixes: 25216afc9db5 ("PCI: Add managed pcim_intx()")
Link: https://lore.kernel.org/87v7xk2ps5.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Philipp Stanner 
Cc: stable@vger.kernel.org	# v6.11+
Signed-off-by: Sasha Levin

PCI: Remove devres from pci_intx()

2025-02-27T12:30:15+00:00

[ Upstream commit dfa2f4d5f9e5d757700cefa8ee480099889f1c69 ]

pci_intx() is a hybrid function which can sometimes be managed through
devres. This hybrid nature is undesirable.

Since all users of pci_intx() have by now been ported either to
always-managed pcim_intx() or never-managed pci_intx_unmanaged(), the
devres functionality can be removed from pci_intx().

Consequently, pci_intx_unmanaged() is now redundant, because pci_intx()
itself is now unmanaged.

Remove the devres functionality from pci_intx(). Have all users of
pci_intx_unmanaged() call pci_intx(). Remove pci_intx_unmanaged().

Link: https://lore.kernel.org/r/20241209130632.132074-13-pstanner@redhat.com
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Acked-by: Paolo Abeni 
Stable-dep-of: d555ed45a5a1 ("PCI: Restore original INTX_DISABLE bit by pcim_intx()")
Signed-off-by: Sasha Levin

PCI: Export pci_intx_unmanaged() and pcim_intx()

2025-02-27T12:30:15+00:00

[ Upstream commit f546e8033d8f3e45d49622f04ca2fde650b80f6d ]

pci_intx() is a hybrid function which sometimes performs devres operations,
depending on whether pcim_enable_device() has been used to enable the
pci_dev. This sometimes-managed nature of the function is problematic.
Notably, it causes the function to allocate under some circumstances which
makes it unusable from interrupt context.

Export pcim_intx() (which is always managed) and rename __pcim_intx()
(which is never managed) to pci_intx_unmanaged() and export it as well.

Then all callers of pci_intx() can be ported to the version they need,
depending whether they use pci_enable_device() or pcim_enable_device().

Link: https://lore.kernel.org/r/20241209130632.132074-3-pstanner@redhat.com
Signed-off-by: Philipp Stanner 
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Damien Le Moal 
Stable-dep-of: d555ed45a5a1 ("PCI: Restore original INTX_DISABLE bit by pcim_intx()")
Signed-off-by: Sasha Levin

PCI: Make pcim_request_all_regions() a public function

2025-02-27T12:30:15+00:00

[ Upstream commit d9d959c36bec59f11c0eb6b5308729e3c4901b5e ]

In order to remove the deprecated function
pcim_iomap_regions_request_all(), a few drivers need an interface to
request all BARs a PCI device offers.

Make pcim_request_all_regions() a public interface.

Link: https://lore.kernel.org/r/20241030112743.104395-2-pstanner@redhat.com
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Damien Le Moal 
Reviewed-by: Ilpo Järvinen 
Stable-dep-of: d555ed45a5a1 ("PCI: Restore original INTX_DISABLE bit by pcim_intx()")
Signed-off-by: Sasha Levin

Merge tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

2024-09-23T19:47:06+00:00

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Wait for device readiness after reset by polling Vendor ID and
     looking for Configuration RRS instead of polling the Command
     register and looking for non-error completions, to avoid hardware
     retries done for RRS on non-Vendor ID reads (Bjorn Helgaas)

   - Rename CRS Completion Status to RRS ('Request Retry Status') to
     match PCIe r6.0 spec usage (Bjorn Helgaas)

   - Clear LBMS bit after a manual link retrain so we don't try to
     retrain a link when there's no downstream device anymore (Maciej W.
     Rozycki)

   - Revert to the original link speed after retraining fails instead of
     leaving it restricted to 2.5GT/s, so a future device has a chance
     to use higher speeds (Maciej W. Rozycki)

   - Wait for each level of downstream bus, not just the first, to
     become accessible before restoring devices on that bus (Ilpo
     Järvinen)

   - Add ARCH_PCI_DEV_GROUPS so s390 can add its own attribute_groups
     without having to stomp on the core's pdev->dev.groups (Lukas
     Wunner)

  Driver binding:

   - Export pcim_request_region(), a managed counterpart of
     pci_request_region(), for use by drivers (Philipp Stanner)

   - Export pcim_iomap_region() and deprecate pcim_iomap_regions()
     (Philipp Stanner)

   - Request the PCI BAR used by xboxvideo (Philipp Stanner)

   - Request and map drm/ast BARs with pcim_iomap_region() (Philipp
     Stanner)

  MSI:

   - Add MSI_FLAG_NO_AFFINITY flag for devices that mux MSIs onto a
     single IRQ line and cannot set the affinity of each MSI to a
     specific CPU core (Marek Vasut)

   - Use MSI_FLAG_NO_AFFINITY and remove unnecessary .irq_set_affinity()
     implementations in aardvark, altera, brcmstb, dwc, mediatek-gen3,
     mediatek, mobiveil, plda, rcar, tegra, vmd, xilinx-nwl,
     xilinx-xdma, and xilinx drivers to avoid 'IRQ: set affinity failed'
     warnings (Marek Vasut)

  Power management:

   - Add pwrctl support for ATH11K inside the WCN6855 package (Konrad
     Dybcio)

  PCI device hotplug:

   - Remove unnecessary hpc_ops struct from shpchp (ngn)

   - Check for PCI_POSSIBLE_ERROR(), not 0xffffffff, in cpqphp
     (weiyufeng)

  Virtualization:

   - Mark Creative Labs EMU20k2 INTx masking as broken (Alex Williamson)

   - Add an ACS quirk for Qualcomm SA8775P, which doesn't advertise ACS
     but does provide ACS-like features (Subramanian Ananthanarayanan)

  IOMMU:

   - Add function 0 DMA alias quirk for Glenfly Arise audio function,
     which uses the function 0 Requester ID (WangYuli)

  NPEM:

   - Add Native PCIe Enclosure Management (NPEM) support for sysfs
     control of NVMe RAID storage indicators (ok/fail/locate/
     rebuild/etc) (Mariusz Tkaczyk)

   - Add support for the ACPI _DSM PCIe SSD status LED management, which
     is functionally similar to NPEM but mediated by platform firmware
     (Mariusz Tkaczyk)

  Device trees:

   - Drop minItems and maxItems from ranges in PCI generic host binding
     since host bridges may have several MMIO and I/O port apertures
     (Frank Li)

   - Add kirin, rcar-gen2, uniphier DT binding top-level constraints for
     clocks (Krzysztof Kozlowski)

  Altera PCIe controller driver:

   - Convert altera DT bindings from text to YAML (Matthew Gerlach)

   - Replace TLP_REQ_ID() with macro PCI_DEVID(), which does the same
     thing and is what other drivers use (Jinjie Ruan)

  Broadcom STB PCIe controller driver:

   - Add DT binding maxItems for reset controllers (Jim Quinlan)

   - Use the 'bridge' reset method if described in the DT (Jim Quinlan)

   - Use the 'swinit' reset method if described in the DT (Jim Quinlan)

   - Add 'has_phy' so the existence of a 'rescal' reset controller
     doesn't imply software control of it (Jim Quinlan)

   - Add support for many inbound DMA windows (Jim Quinlan)

   - Rename SoC 'type' to 'soc_base' express the fact that SoCs come in
     families of multiple similar devices (Jim Quinlan)

   - Add Broadcom 7712 DT description and driver support (Jim Quinlan)

   - Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings for
     maintainability (Bjorn Helgaas)

  Freescale i.MX6 PCIe controller driver:

   - Add imx6q-pcie 'dbi2' and 'atu' reg-names for i.MX8M Endpoints
     (Richard Zhu)

   - Fix a code restructuring error that caused i.MX8MM and i.MX8MP
     Endpoints to fail to establish link (Richard Zhu)

   - Fix i.MX8MP Endpoint occasional failure to trigger MSI by enforcing
     outbound alignment requirement (Richard Zhu)

   - Call phy_power_off() in the .probe() error path (Frank Li)

   - Rename internal names from imx6_* to imx_* since i.MX7/8/9 are also
     supported (Frank Li)

   - Manage Refclk by using SoC-specific callbacks instead of switch
     statements (Frank Li)

   - Manage core reset by using SoC-specific callbacks instead of switch
     statements (Frank Li)

   - Expand comments for erratum ERR010728 workaround (Frank Li)

   - Use generic PHY APIs to configure mode, speed, and submode, which
     is harmless for devices that implement their own internal PHY
     management and don't set the generic imx_pcie->phy (Frank Li)

   - Add i.MX8Q (i.MX8QM, i.MX8QXP, and i.MX8DXL) DT binding and driver
     Root Complex support (Richard Zhu)

  Freescale Layerscape PCIe controller driver:

   - Replace layerscape-pcie DT binding compatible fsl,lx2160a-pcie with
     fsl,lx2160ar2-pcie (Frank Li)

   - Add layerscape-pcie DT binding deprecated 'num-viewport' property
     to address a DT checker warning (Frank Li)

   - Change layerscape-pcie DT binding 'fsl,pcie-scfg' to phandle-array
     (Frank Li)

  Loongson PCIe controller driver:

   - Increase max PCI hosts to 8 for Loongson-3C6000 and newer chipsets
     (Huacai Chen)

  Marvell Aardvark PCIe controller driver:

   - Fix issue with emulating Configuration RRS for two-byte reads of
     Vendor ID; previously it only worked for four-byte reads (Bjorn
     Helgaas)

  MediaTek PCIe Gen3 controller driver:

   - Add per-SoC struct mtk_gen3_pcie_pdata to support multiple SoC
     types (Lorenzo Bianconi)

   - Use reset_bulk APIs to manage PHY reset lines (Lorenzo Bianconi)

   - Add DT and driver support for Airoha EN7581 PCIe controller
     (Lorenzo Bianconi)

  Qualcomm PCIe controller driver:

   - Update qcom,pcie-sc7280 DT binding with eight interrupts (Rayyan
     Ansari)

   - Add back DT 'vddpe-3v3-supply', which was incorrectly removed
     earlier (Johan Hovold)

   - Drop endpoint redundant masking of global IRQ events (Manivannan
     Sadhasivam)

   - Clarify unknown global IRQ message and only log it once to avoid a
     flood (Manivannan Sadhasivam)

   - Add 'linux,pci-domain' property to endpoint DT binding (Manivannan
     Sadhasivam)

   - Assign PCI domain number for endpoint controllers (Manivannan
     Sadhasivam)

   - Add 'qcom_pcie_ep' and the PCI domain number to IRQ names for
     endpoint controller (Manivannan Sadhasivam)

   - Add global SPI interrupt for PCIe link events to DT binding
     (Manivannan Sadhasivam)

   - Add global RC interrupt handler to handle 'Link up' events and
     automatically enumerate hot-added devices (Manivannan Sadhasivam)

   - Avoid mirroring of DBI and iATU register space so it doesn't
     overlap BAR MMIO space (Prudhvi Yarlagadda)

   - Enable controller resources like PHY only after PERST# is
     deasserted to partially avoid the problem that the endpoint SoC
     crashes when accessing things when Refclk is absent (Manivannan
     Sadhasivam)

   - Add 16.0 GT/s equalization and RX lane margining settings (Shashank
     Babu Chinta Venkata)

   - Pass domain number to pci_bus_release_domain_nr() explicitly to
     avoid a NULL pointer dereference (Manivannan Sadhasivam)

  Renesas R-Car PCIe controller driver:

   - Make the read-only const array 'check_addr' static (Colin Ian King)

   - Add R-Car V4M (R8A779H0) PCIe host and endpoint to DT binding
     (Yoshihiro Shimoda)

  TI DRA7xx PCIe controller driver:

   - Request IRQF_ONESHOT for 'dra7xx-pcie-main' IRQ since the primary
     handler is NULL (Siddharth Vadapalli)

   - Handle IRQ request errors during root port and endpoint probe
     (Siddharth Vadapalli)

  TI J721E PCIe driver:

   - Add DT 'ti,syscon-acspcie-proxy-ctrl' and driver support to enable
     the ACSPCIE module to drive Refclk for the Endpoint (Siddharth
     Vadapalli)

   - Extract the cadence link setup from cdns_pcie_host_setup() so link
     setup can be done separately during resume (Thomas Richard)

   - Add T_PERST_CLK_US definition for the mandatory delay between
     Refclk becoming stable and PERST# being deasserted (Thomas Richard)

   - Add j721e suspend and resume support (Théo Lebrun)

  TI Keystone PCIe controller driver:

   - Fix NULL pointer checking when applying MRRS limitation quirk for
     AM65x SR 1.0 Errata #i2037 (Dan Carpenter)

  Xilinx NWL PCIe controller driver:

   - Fix off-by-one error in INTx IRQ handler that caused INTx
     interrupts to be lost or delivered as the wrong interrupt (Sean
     Anderson)

   - Rate-limit misc interrupt messages (Sean Anderson)

   - Turn off the clock on probe failure and device removal (Sean
     Anderson)

   - Add DT binding and driver support for enabling/disabling PHYs (Sean
     Anderson)

   - Add PCIe phy bindings for the ZCU102 (Sean Anderson)

  Xilinx XDMA PCIe controller driver:

   - Add support for Xilinx QDMA Soft IP PCIe Root Port Bridge to DT
     binding and xilinx-dma-pl driver (Thippeswamy Havalige)

  Miscellaneous:

   - Fix buffer overflow in kirin_pcie_parse_port() (Alexandra Diupina)

   - Fix minor kerneldoc issues and typos (Bjorn Helgaas)

   - Use PCI_DEVID() macro in aer_inject() instead of open-coding it
     (Jinjie Ruan)

   - Check pcie_find_root_port() return in x86 fixups to avoid NULL
     pointer dereferences (Samasth Norway Ananda)

   - Make pci_bus_type constant (Kunwu Chan)

   - Remove unused declarations of __pci_pme_wakeup() and
     pci_vpd_release() (Yue Haibing)

   - Remove any leftover .*.cmd files with make clean (zhang jiao)

   - Remove unused BILLION macro (zhang jiao)"

* tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (132 commits)
  PCI: Fix typos
  dt-bindings: PCI: qcom: Allow 'vddpe-3v3-supply' again
  tools: PCI: Remove unused BILLION macro
  tools: PCI: Remove .*.cmd files with make clean
  PCI: Pass domain number to pci_bus_release_domain_nr() explicitly
  PCI: dra7xx: Fix error handling when IRQ request fails in probe
  PCI: dra7xx: Fix threaded IRQ request for "dra7xx-pcie-main" IRQ
  PCI: qcom: Add RX lane margining settings for 16.0 GT/s
  PCI: qcom: Add equalization settings for 16.0 GT/s
  PCI: dwc: Always cache the maximum link speed value in dw_pcie::max_link_speed
  PCI: dwc: Rename 'dw_pcie::link_gen' to 'dw_pcie::max_link_speed'
  PCI: qcom-ep: Enable controller resources like PHY only after refclk is available
  PCI: Mark Creative Labs EMU20k2 INTx masking as broken
  dt-bindings: PCI: imx6q-pcie: Add reg-name "dbi2" and "atu" for i.MX8M PCIe Endpoint
  dt-bindings: PCI: altera: msi: Convert to YAML
  PCI: imx6: Add i.MX8Q PCIe Root Complex (RC) support
  PCI: Rename CRS Completion Status to RRS
  PCI: aardvark: Correct Configuration RRS checking
  PCI: Wait for device readiness with Configuration RRS
  PCI: brcmstb: Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings
  ...

PCI: Fix potential deadlock in pcim_intx()

2024-09-12T12:52:50+00:00

25216afc9db5 ("PCI: Add managed pcim_intx()") moved the allocation step for
pci_intx()'s device resource from pcim_enable_device() to pcim_intx(). As
before, pcim_enable_device() sets pci_dev.is_managed to true; and it is
never set to false again.

Due to the lifecycle of a struct pci_dev, it can happen that a second
driver obtains the same pci_dev after a first driver ran.  If one driver
uses pcim_enable_device() and the other doesn't, this causes the other
driver to run into managed pcim_intx(), which will try to allocate when
called for the first time.

Allocations might sleep, so calling pci_intx() while holding spinlocks
becomes then invalid, which causes lockdep warnings and could cause
deadlocks:

  ========================================================
  WARNING: possible irq lock inversion dependency detected
  6.11.0-rc6+ #59 Tainted: G        W
  --------------------------------------------------------
  CPU 0/KVM/1537 just changed the state of lock:
  ffffa0f0cff965f0 (&vdev->irqlock){-...}-{2:2}, at:
  vfio_intx_handler+0x21/0xd0 [vfio_pci_core] but this lock took another,
  HARDIRQ-unsafe lock in the past: (fs_reclaim){+.+.}-{0:0}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:

  Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
			       local_irq_disable();
			       lock(&vdev->irqlock);
			       lock(fs_reclaim);
  
    lock(&vdev->irqlock);

  *** DEADLOCK ***

Have pcim_enable_device()'s release function, pcim_disable_device(), set
pci_dev.is_managed to false so that subsequent drivers using the same
struct pci_dev do not implicitly run into managed code.

Link: https://lore.kernel.org/r/20240905072556.11375-2-pstanner@redhat.com
Fixes: 25216afc9db5 ("PCI: Add managed pcim_intx()")
Reported-by: Alex Williamson 
Closes: https://lore.kernel.org/all/20240903094431.63551744.alex.williamson@redhat.com/
Suggested-by: Alex Williamson 
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Tested-by: Alex Williamson 
Reviewed-by: Damien Le Moal

PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

2024-08-09T20:08:35+00:00

pcim_iomap_regions() is a complicated function that uses a bit mask to
determine the BARs the user wishes to request and ioremap. Almost all users
only ever set a single bit in that mask, making that mechanism
questionable.

pcim_iomap_region() is now available as a more simple replacement.

Make pcim_iomap_region() a public function.

Mark pcim_iomap_regions() as deprecated.

Link: https://lore.kernel.org/r/20240807083018.8734-2-pstanner@redhat.com
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas

PCI: Make pcim_request_region() a public function

2024-08-09T20:08:18+00:00

pcim_request_region() is the managed counterpart of pci_request_region().
It is currently only used internally for PCI.

It can be useful for a number of drivers and exporting it is a step towards
deprecating more complicated functions.

Make pcim_request_region() a public function.

Link: https://lore.kernel.org/r/20240729093625.17561-4-pstanner@redhat.com
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Tested-by: Hans de Goede 
Reviewed-by: Hans de Goede 
Acked-by: Hans de Goede