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Filename Latest commit message Latest commit date
Maciej W. Rozycki e3f7e99337 PCI: Sanitise firmware BAR assignments behind a PCI-PCI bridge
commit 0e32818397426a688f598f35d3bc762eca6d7592 upstream.

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

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

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

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

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

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

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

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

[bhelgaas: commit log, use pci_upstream_bridge()]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=16263
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203012338460.46819@angie.orcam.me.uk
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209211921250.29493@angie.orcam.me.uk
Fixes: 58c84eda07 ("PCI: fall back to original BIOS BAR addresses")
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v2.6.35+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 13:22:16 +02:00
arch UM: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK 2022-10-26 13:22:16 +02:00
block
certs
crypto
Documentation ARM: dts: fix Moxa SDIO 'compatible', remove 'sdhci' misnomer 2022-10-15 07:54:37 +02:00
drivers PCI: Sanitise firmware BAR assignments behind a PCI-PCI bridge 2022-10-26 13:22:16 +02:00
fs quota: Check next/prev free block number after reading from quota file 2022-10-26 13:22:14 +02:00
include scsi: stex: Properly zero out the passthrough command structure 2022-10-15 07:54:39 +02:00
init
ipc
kernel workqueue: don't skip lockdep work dependency in cancel_work_sync() 2022-09-28 11:04:09 +02:00
lib lib/vdso: Mark do_hres() and do_coarse() as __always_inline 2022-09-05 10:27:47 +02:00
LICENSES
mm mm: pagewalk: Fix race between unmap and page walker 2022-10-15 07:54:36 +02:00
net wifi: mac80211: fix MBSSID parsing use-after-free 2022-10-17 17:24:32 +02:00
samples
scripts Makefile.extrawarn: Move -Wcast-function-type-strict to W=1 2022-10-07 09:16:57 +02:00
security efi: Correct Macmini DMI match in uefi cert quirk 2022-10-15 07:54:39 +02:00
sound ASoC: wcd9335: fix order of Slimbus unprepare/disable 2022-10-26 13:22:14 +02:00
tools perf tools: Fixup get_current_dir_name() compilation 2022-10-15 07:54:36 +02:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS MAINTAINERS: add Chandan as xfs maintainer for 5.4.y 2022-09-28 11:03:58 +02:00
Makefile Linux 5.4.219 2022-10-17 17:24:32 +02:00
README

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