linux-stable.git/include/linux/pci.h, branch v5.4.301 Linux kernel stable tree PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable ports 2025-08-28T14:21:33+00:00 Lukas Wunner lukas@wunner.de 2025-07-13T14:31:01+00:00 607b3426547701efcc4f3d39ce05137497601909 commit 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a upstream. pci_bridge_d3_possible() is called from both pcie_portdrv_probe() and pcie_portdrv_remove() to determine whether runtime power management shall be enabled (on probe) or disabled (on remove) on a PCIe port. The underlying assumption is that pci_bridge_d3_possible() always returns the same value, else a runtime PM reference imbalance would occur. That assumption is not given if the PCIe port is inaccessible on remove due to hot-unplug: pci_bridge_d3_possible() calls pciehp_is_native(), which accesses Config Space to determine whether the port is Hot-Plug Capable. An inaccessible port returns "all ones", which is converted to "all zeroes" by pcie_capability_read_dword(). Hence the port no longer seems Hot-Plug Capable on remove even though it was on probe. The resulting runtime PM ref imbalance causes warning messages such as: pcieport 0000:02:04.0: Runtime PM usage count underflow! Avoid the Config Space access (and thus the runtime PM ref imbalance) by caching the Hot-Plug Capable bit in struct pci_dev. The struct already contains an "is_hotplug_bridge" flag, which however is not only set on Hot-Plug Capable PCIe ports, but also Conventional PCI Hot-Plug bridges and ACPI slots. The flag identifies bridges which are allocated additional MMIO and bus number resources to allow for hierarchy expansion. The kernel is somewhat sloppily using "is_hotplug_bridge" in a number of places to identify Hot-Plug Capable PCIe ports, even though the flag encompasses other devices. Subsequent commits replace these occurrences with the new flag to clearly delineate Hot-Plug Capable PCIe ports from other kinds of hotplug bridges. Document the existing "is_hotplug_bridge" and the new "is_pciehp" flag and document the (non-obvious) requirement that pci_bridge_d3_possible() always returns the same value across the entire lifetime of a bridge, including its hot-removal. Fixes: 5352a44a561d ("PCI: pciehp: Make pciehp_is_native() stricter") Reported-by: Laurent Bigonville <bigon@bigon.be> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220216 Reported-by: Mario Limonciello <mario.limonciello@amd.com> Closes: https://lore.kernel.org/r/20250609020223.269407-3-superm1@kernel.org/ Link: https://lore.kernel.org/all/20250620025535.3425049-3-superm1@kernel.org/T/#u Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Cc: stable@vger.kernel.org # v4.18+ Link: https://patch.msgid.link/fe5dcc3b2e62ee1df7905d746bde161eb1b3291c.1752390101.git.lukas@wunner.de [ Adjust surrounding documentation changes ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a upstream.

pci_bridge_d3_possible() is called from both pcie_portdrv_probe() and
pcie_portdrv_remove() to determine whether runtime power management shall
be enabled (on probe) or disabled (on remove) on a PCIe port.

The underlying assumption is that pci_bridge_d3_possible() always returns
the same value, else a runtime PM reference imbalance would occur.  That
assumption is not given if the PCIe port is inaccessible on remove due to
hot-unplug:  pci_bridge_d3_possible() calls pciehp_is_native(), which
accesses Config Space to determine whether the port is Hot-Plug Capable.
An inaccessible port returns "all ones", which is converted to "all
zeroes" by pcie_capability_read_dword().  Hence the port no longer seems
Hot-Plug Capable on remove even though it was on probe.

The resulting runtime PM ref imbalance causes warning messages such as:

  pcieport 0000:02:04.0: Runtime PM usage count underflow!

Avoid the Config Space access (and thus the runtime PM ref imbalance) by
caching the Hot-Plug Capable bit in struct pci_dev.

The struct already contains an "is_hotplug_bridge" flag, which however is
not only set on Hot-Plug Capable PCIe ports, but also Conventional PCI
Hot-Plug bridges and ACPI slots.  The flag identifies bridges which are
allocated additional MMIO and bus number resources to allow for hierarchy
expansion.

The kernel is somewhat sloppily using "is_hotplug_bridge" in a number of
places to identify Hot-Plug Capable PCIe ports, even though the flag
encompasses other devices.  Subsequent commits replace these occurrences
with the new flag to clearly delineate Hot-Plug Capable PCIe ports from
other kinds of hotplug bridges.

Document the existing "is_hotplug_bridge" and the new "is_pciehp" flag
and document the (non-obvious) requirement that pci_bridge_d3_possible()
always returns the same value across the entire lifetime of a bridge,
including its hot-removal.

Fixes: 5352a44a561d ("PCI: pciehp: Make pciehp_is_native() stricter")
Reported-by: Laurent Bigonville <bigon@bigon.be>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220216
Reported-by: Mario Limonciello <mario.limonciello@amd.com>
Closes: https://lore.kernel.org/r/20250609020223.269407-3-superm1@kernel.org/
Link: https://lore.kernel.org/all/20250620025535.3425049-3-superm1@kernel.org/T/#u
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Cc: stable@vger.kernel.org # v4.18+
Link: https://patch.msgid.link/fe5dcc3b2e62ee1df7905d746bde161eb1b3291c.1752390101.git.lukas@wunner.de
[ Adjust surrounding documentation changes ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PCI: Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX 2025-05-02T05:39:25+00:00 Bjorn Helgaas bhelgaas@google.com 2023-11-22T06:03:51+00:00 f4a9f4dd994613efb9e50f8978c9c882010dc645 [ Upstream commit 58ff9c5acb4aef58e118bbf39736cc4d6c11a3d3 ] Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX to be more explicit about the type of IRQ being referenced as well as to match the PCI specifications terms. Redefine PCI_IRQ_LEGACY as an alias to PCI_IRQ_INTX to avoid the need for doing the renaming tree-wide. New drivers and new code should now prefer using PCI_IRQ_INTX instead of PCI_IRQ_LEGACY. Link: https://lore.kernel.org/r/20231122060406.14695-2-dlemoal@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Stable-dep-of: 919d14603dab ("misc: pci_endpoint_test: Fix displaying 'irq_type' after 'request_irq' error") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 58ff9c5acb4aef58e118bbf39736cc4d6c11a3d3 ]

Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX to be more explicit about the type
of IRQ being referenced as well as to match the PCI specifications
terms. Redefine PCI_IRQ_LEGACY as an alias to PCI_IRQ_INTX to avoid the
need for doing the renaming tree-wide. New drivers and new code should
now prefer using PCI_IRQ_INTX instead of PCI_IRQ_LEGACY.

Link: https://lore.kernel.org/r/20231122060406.14695-2-dlemoal@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Stable-dep-of: 919d14603dab ("misc: pci_endpoint_test: Fix displaying 'irq_type' after 'request_irq' error")
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: Add PCI_ERROR_RESPONSE and related definitions 2024-07-05T07:08:25+00:00 Naveen Naidu naveennaidu479@gmail.com 2021-11-18T14:03:11+00:00 91870a211a80eab73900c5a7c53869018d2f19dd [ Upstream commit 57bdeef4716689d9b0e3571034d65cf420f6efcd ] A config or MMIO read from a PCI device that doesn't exist or doesn't respond causes a PCI error. There's no real data to return to satisfy the CPU read, so most hardware fabricates ~0 data. Add a PCI_ERROR_RESPONSE definition for that and use it where appropriate to make these checks consistent and easier to find. Also add helper definitions PCI_SET_ERROR_RESPONSE() and PCI_POSSIBLE_ERROR() to make the code more readable. Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/55563bf4dfc5d3fdc96695373c659d099bf175b1.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Pali Rohár <pali@kernel.org> Stable-dep-of: c625dabbf1c4 ("x86/amd_nb: Check for invalid SMN reads") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 57bdeef4716689d9b0e3571034d65cf420f6efcd ]

A config or MMIO read from a PCI device that doesn't exist or doesn't
respond causes a PCI error. There's no real data to return to satisfy the
CPU read, so most hardware fabricates ~0 data.

Add a PCI_ERROR_RESPONSE definition for that and use it where appropriate
to make these checks consistent and easier to find.

Also add helper definitions PCI_SET_ERROR_RESPONSE() and
PCI_POSSIBLE_ERROR() to make the code more readable.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/55563bf4dfc5d3fdc96695373c659d099bf175b1.1637243717.git.naveennaidu479@gmail.com
Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pali Rohár <pali@kernel.org>
Stable-dep-of: c625dabbf1c4 ("x86/amd_nb: Check for invalid SMN reads")
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: Add pci_clear_master() stub for non-CONFIG_PCI 2023-07-27T06:37:16+00:00 Sui Jingfeng suijingfeng@loongson.cn 2023-05-31T10:27:44+00:00 1768e362f20fb6e1439bc0845946936937ce1240 [ Upstream commit 2aa5ac633259843f656eb6ecff4cf01e8e810c5e ] Add a pci_clear_master() stub when CONFIG_PCI is not set so drivers that support both PCI and platform devices don't need #ifdefs or extra Kconfig symbols for the PCI parts. [bhelgaas: commit log] Fixes: 6a479079c072 ("PCI: Add pci_clear_master() as opposite of pci_set_master()") Link: https://lore.kernel.org/r/20230531102744.2354313-1-suijingfeng@loongson.cn Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2aa5ac633259843f656eb6ecff4cf01e8e810c5e ]

Add a pci_clear_master() stub when CONFIG_PCI is not set so drivers that
support both PCI and platform devices don't need #ifdefs or extra Kconfig
symbols for the PCI parts.

[bhelgaas: commit log]
Fixes: 6a479079c072 ("PCI: Add pci_clear_master() as opposite of pci_set_master()")
Link: https://lore.kernel.org/r/20230531102744.2354313-1-suijingfeng@loongson.cn
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: Reduce warnings on possible RW1C corruption 2022-04-15T12:18:15+00:00 Mark Tomlinson mark.tomlinson@alliedtelesis.co.nz 2020-08-06T04:14:55+00:00 10705a4305579518da06662c045a90a4bcdd15f7 [ Upstream commit 92c45b63ce22c8898aa41806e8d6692bcd577510 ] For hardware that only supports 32-bit writes to PCI there is the possibility of clearing RW1C (write-one-to-clear) bits. A rate-limited messages was introduced by fb2659230120, but rate-limiting is not the best choice here. Some devices may not show the warnings they should if another device has just produced a bunch of warnings. Also, the number of messages can be a nuisance on devices which are otherwise working fine. Change the ratelimit to a single warning per bus. This ensures no bus is 'starved' of emitting a warning and also that there isn't a continuous stream of warnings. It would be preferable to have a warning per device, but the pci_dev structure is not available here, and a lookup from devfn would be far too slow. Suggested-by: Bjorn Helgaas <helgaas@kernel.org> Fixes: fb2659230120 ("PCI: Warn on possible RW1C corruption for sub-32 bit config writes") Link: https://lore.kernel.org/r/20200806041455.11070-1-mark.tomlinson@alliedtelesis.co.nz Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 92c45b63ce22c8898aa41806e8d6692bcd577510 ]

For hardware that only supports 32-bit writes to PCI there is the
possibility of clearing RW1C (write-one-to-clear) bits. A rate-limited
messages was introduced by fb2659230120, but rate-limiting is not the best
choice here. Some devices may not show the warnings they should if another
device has just produced a bunch of warnings. Also, the number of messages
can be a nuisance on devices which are otherwise working fine.

Change the ratelimit to a single warning per bus. This ensures no bus is
'starved' of emitting a warning and also that there isn't a continuous
stream of warnings. It would be preferable to have a warning per device,
but the pci_dev structure is not available here, and a lookup from devfn
would be far too slow.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Fixes: fb2659230120 ("PCI: Warn on possible RW1C corruption for sub-32 bit config writes")
Link: https://lore.kernel.org/r/20200806041455.11070-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI/MSI: Deal with devices lying about their MSI mask capability 2021-11-21T12:38:50+00:00 Marc Zyngier maz@kernel.org 2021-11-04T18:01:29+00:00 db1390b60e89ef6c5eb99b229365bb5a00a5b608 commit 2226667a145db2e1f314d7f57fd644fe69863ab9 upstream. It appears that some devices are lying about their mask capability, pretending that they don't have it, while they actually do. The net result is that now that we don't enable MSIs on such endpoint. Add a new per-device flag to deal with this. Further patches will make use of it, sadly. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20211104180130.3825416-2-maz@kernel.org Cc: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 2226667a145db2e1f314d7f57fd644fe69863ab9 upstream.

It appears that some devices are lying about their mask capability,
pretending that they don't have it, while they actually do.
The net result is that now that we don't enable MSIs on such
endpoint.

Add a new per-device flag to deal with this. Further patches will
make use of it, sadly.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20211104180130.3825416-2-maz@kernel.org
Cc: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PCI: Sync __pci_register_driver() stub for CONFIG_PCI=n 2021-09-22T10:26:45+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2021-08-13T15:36:19+00:00 14e0fdc43ddfb052580e3ebb6e4806f0cf087fc0 [ Upstream commit 817f9916a6e96ae43acdd4e75459ef4f92d96eb1 ] The CONFIG_PCI=y case got a new parameter long time ago. Sync the stub as well. [bhelgaas: add parameter names] Fixes: 725522b5453d ("PCI: add the sysfs driver name to all modules") Link: https://lore.kernel.org/r/20210813153619.89574-1-andriy.shevchenko@linux.intel.com Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 817f9916a6e96ae43acdd4e75459ef4f92d96eb1 ]

The CONFIG_PCI=y case got a new parameter long time ago.  Sync the stub as
well.

[bhelgaas: add parameter names]
Fixes: 725522b5453d ("PCI: add the sysfs driver name to all modules")
Link: https://lore.kernel.org/r/20210813153619.89574-1-andriy.shevchenko@linux.intel.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI/IOV: Mark VFs as not implementing PCI_COMMAND_MEMORY 2020-10-29T08:57:54+00:00 Matthew Rosato mjrosato@linux.ibm.com 2020-09-10T14:59:55+00:00 42f16b3add6c3dde6751e5f8f7c2fab6bcc73250 [ Upstream commit 12856e7acde4702b7c3238c15fcba86ff6aa507f ] For VFs, the Memory Space Enable bit in the Command Register is hard-wired to 0. Add a new bit to signify devices where the Command Register Memory Space Enable bit does not control the device's response to MMIO accesses. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 12856e7acde4702b7c3238c15fcba86ff6aa507f ]

For VFs, the Memory Space Enable bit in the Command Register is
hard-wired to 0.

Add a new bit to signify devices where the Command Register Memory
Space Enable bit does not control the device's response to MMIO
accesses.

Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory")
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: Use ioremap(), not phys_to_virt() for platform ROM 2020-10-01T11:17:51+00:00 Mikel Rychliski mikel@mikelr.com 2020-03-19T02:16:23+00:00 535943c46dfcf32018d94da0b8c9ba470a9a8e71 [ Upstream commit 72e0ef0e5f067fd991f702f0b2635d911d0cf208 ] On some EFI systems, the video BIOS is provided by the EFI firmware. The boot stub code stores the physical address of the ROM image in pdev->rom. Currently we attempt to access this pointer using phys_to_virt(), which doesn't work with CONFIG_HIGHMEM. On these systems, attempting to load the radeon module on a x86_32 kernel can result in the following: BUG: unable to handle page fault for address: 3e8ed03c #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page *pde = 00000000 Oops: 0000 [#1] PREEMPT SMP CPU: 0 PID: 317 Comm: systemd-udevd Not tainted 5.6.0-rc3-next-20200228 #2 Hardware name: Apple Computer, Inc. MacPro1,1/Mac-F4208DC8, BIOS MP11.88Z.005C.B08.0707021221 07/02/07 EIP: radeon_get_bios+0x5ed/0xe50 [radeon] Code: 00 00 84 c0 0f 85 12 fd ff ff c7 87 64 01 00 00 00 00 00 00 8b 47 08 8b 55 b0 e8 1e 83 e1 d6 85 c0 74 1a 8b 55 c0 85 d2 74 13 <80> 38 55 75 0e 80 78 01 aa 0f 84 a4 03 00 00 8d 74 26 00 68 dc 06 EAX: 3e8ed03c EBX: 00000000 ECX: 3e8ed03c EDX: 00010000 ESI: 00040000 EDI: eec04000 EBP: eef3fc60 ESP: eef3fbe0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010206 CR0: 80050033 CR2: 3e8ed03c CR3: 2ec77000 CR4: 000006d0 Call Trace: r520_init+0x26/0x240 [radeon] radeon_device_init+0x533/0xa50 [radeon] radeon_driver_load_kms+0x80/0x220 [radeon] drm_dev_register+0xa7/0x180 [drm] radeon_pci_probe+0x10f/0x1a0 [radeon] pci_device_probe+0xd4/0x140 Fix the issue by updating all drivers which can access a platform provided ROM. Instead of calling the helper function pci_platform_rom() which uses phys_to_virt(), call ioremap() directly on the pdev->rom. radeon_read_platform_bios() previously directly accessed an __iomem pointer. Avoid this by calling memcpy_fromio() instead of kmemdup(). pci_platform_rom() now has no remaining callers, so remove it. Link: https://lore.kernel.org/r/20200319021623.5426-1-mikel@mikelr.com Signed-off-by: Mikel Rychliski <mikel@mikelr.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 72e0ef0e5f067fd991f702f0b2635d911d0cf208 ]

On some EFI systems, the video BIOS is provided by the EFI firmware.  The
boot stub code stores the physical address of the ROM image in pdev->rom.
Currently we attempt to access this pointer using phys_to_virt(), which
doesn't work with CONFIG_HIGHMEM.

On these systems, attempting to load the radeon module on a x86_32 kernel
can result in the following:

  BUG: unable to handle page fault for address: 3e8ed03c
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  *pde = 00000000
  Oops: 0000 [#1] PREEMPT SMP
  CPU: 0 PID: 317 Comm: systemd-udevd Not tainted 5.6.0-rc3-next-20200228 #2
  Hardware name: Apple Computer, Inc. MacPro1,1/Mac-F4208DC8, BIOS     MP11.88Z.005C.B08.0707021221 07/02/07
  EIP: radeon_get_bios+0x5ed/0xe50 [radeon]
  Code: 00 00 84 c0 0f 85 12 fd ff ff c7 87 64 01 00 00 00 00 00 00 8b 47 08 8b 55 b0 e8 1e 83 e1 d6 85 c0 74 1a 8b 55 c0 85 d2 74 13 <80> 38 55 75 0e 80 78 01 aa 0f 84 a4 03 00 00 8d 74 26 00 68 dc 06
  EAX: 3e8ed03c EBX: 00000000 ECX: 3e8ed03c EDX: 00010000
  ESI: 00040000 EDI: eec04000 EBP: eef3fc60 ESP: eef3fbe0
  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010206
  CR0: 80050033 CR2: 3e8ed03c CR3: 2ec77000 CR4: 000006d0
  Call Trace:
   r520_init+0x26/0x240 [radeon]
   radeon_device_init+0x533/0xa50 [radeon]
   radeon_driver_load_kms+0x80/0x220 [radeon]
   drm_dev_register+0xa7/0x180 [drm]
   radeon_pci_probe+0x10f/0x1a0 [radeon]
   pci_device_probe+0xd4/0x140

Fix the issue by updating all drivers which can access a platform provided
ROM. Instead of calling the helper function pci_platform_rom() which uses
phys_to_virt(), call ioremap() directly on the pdev->rom.

radeon_read_platform_bios() previously directly accessed an __iomem
pointer. Avoid this by calling memcpy_fromio() instead of kmemdup().

pci_platform_rom() now has no remaining callers, so remove it.

Link: https://lore.kernel.org/r/20200319021623.5426-1-mikel@mikelr.com
Signed-off-by: Mikel Rychliski <mikel@mikelr.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: Add nr_devfns parameter to pci_add_dma_alias() 2020-02-24T07:36:37+00:00 James Sewart jamessewart@arista.com 2019-12-10T22:07:30+00:00 27a35f09367f0fe6e8d6a525be2447d7a66b90ca [ Upstream commit 09298542cd891b43778db1f65aa3613aa5a562eb ] Add a "nr_devfns" parameter to pci_add_dma_alias() so it can be used to create DMA aliases for a range of devfns. [bhelgaas: incorporate nr_devfns fix from James, update quirk_pex_vca_alias() and setup_aliases()] Signed-off-by: James Sewart <jamessewart@arista.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 09298542cd891b43778db1f65aa3613aa5a562eb ]

Add a "nr_devfns" parameter to pci_add_dma_alias() so it can be used to
create DMA aliases for a range of devfns.

[bhelgaas: incorporate nr_devfns fix from James, update
quirk_pex_vca_alias() and setup_aliases()]
Signed-off-by: James Sewart <jamessewart@arista.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>