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Ilpo Järvinen 91c4c89db4 PCI: Prevent resource tree corruption when BAR resize fails
pbus_reassign_bridge_resources() saves bridge windows into the saved
list before attempting to adjust resource assignments to perform a BAR
resize operation. If resource adjustments cannot be completed fully,
rollback is attempted by restoring the resource from the saved list.

The rollback, however, does not check whether the resources it restores were
assigned by the partial resize attempt. If restore changes addresses of the
resource, it can result in corrupting the resource tree.

An example of a corrupted resource tree with overlapping addresses:

  6200000000000-6203fbfffffff : pciex@620c3c0000000
    6200000000000-6203fbff0ffff : PCI Bus 0030:01
      6200020000000-62000207fffff : 0030:01:00.0
      6200000000000-6203fbff0ffff : PCI Bus 0030:02

A resource that are assigned into the resource tree must remain
unchanged. Thus, release such a resource before attempting to restore
and claim it back.

For simplicity, always do the release and claim back for the resource
even in the cases where it is restored to the same address range.

Note: this fix may "break" some cases where devices "worked" because
the resource tree corruption allowed address space double counting to
fit more resource than what can now be assigned without double
counting. The upcoming changes to BAR resizing should address those
scenarios (to the extent possible).

Fixes: 8bb705e3e7 ("PCI: Add pci_resize_resource() for resizing BARs")
Reported-by: Simon Richter <Simon.Richter@hogyros.de>
Link: https://lore.kernel.org/linux-pci/67840a16-99b4-4d8c-9b5c-4721ab0970a2@hogyros.de/
Reported-by: Alex Bennée <alex.bennee@linaro.org>
Link: https://lore.kernel.org/linux-pci/874irqop6b.fsf@draig.linaro.org/
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Alex Bennée <alex.bennee@linaro.org> # AVA, AMD GPU
Link: https://patch.msgid.link/20251113162628.5946-2-ilpo.jarvinen@linux.intel.com
2025-11-14 12:31:55 -06:00
arch Kbuild fixes for 6.18 #1 2025-10-11 15:47:12 -07:00
block block-6.18-20251009 2025-10-10 10:37:13 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto This push contains the following changes: 2025-10-10 08:56:16 -07:00
Documentation RTC for 6.18 2025-10-11 11:56:47 -07:00
drivers PCI: Prevent resource tree corruption when BAR resize fails 2025-11-14 12:31:55 -06:00
fs - Avoid -Wflex-array-member-not-at-end warnings 2025-10-10 14:06:02 -07:00
include Revert "i2c: boardinfo: Annotate code used in init phase only" 2025-10-11 23:57:33 +02:00
init printk changes for 6.18 2025-10-04 11:13:11 -07:00
io_uring io_uring/zcrx: increment fallback loop src offset 2025-10-08 07:26:14 -06:00
ipc namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
kernel tracing fixes for v6.18: 2025-10-11 16:06:04 -07:00
lib lib/test_kho: use kho_preserve_vmalloc instead of storing addresses in fdt 2025-10-07 13:48:56 -07:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm slab hotfix for 6.18-rc1 2025-10-11 10:40:24 -07:00
net bpf-fixes 2025-10-11 10:31:38 -07:00
rust 7 hotfixes. All 7 are cc:stable and all 7 are for MM. 2025-10-11 10:14:55 -07:00
samples Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
scripts Kbuild fixes for 6.18 #1 2025-10-11 15:47:12 -07:00
security integrity-v6.18 2025-10-05 10:48:33 -07:00
sound sound fixes for 6.18-rc1 2025-10-10 09:55:19 -07:00
tools - Remove a bunch of asm implementing condition flags testing in KVM's 2025-10-11 11:19:16 -07:00
usr gen_init_cpio: Ignore fsync() returning EINVAL on pipes 2025-10-07 09:53:05 -07:00
virt hyperv-next for v6.18 2025-10-07 08:40:15 -07:00
.clang-format memblock: drop for_each_free_mem_pfn_range_in_zone_from() 2025-09-14 08:49:03 +03:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore compile_commands.json globally 2025-08-12 15:53:55 -07:00
.mailmap MAINTAINERS, .mailmap: update Umang's email address 2025-10-07 13:48:55 -07:00
.pylintrc tools: docs: parse-headers.py: move it from sphinx dir 2025-08-29 15:54:42 -06:00
.rustfmt.toml
COPYING
CREDITS USB/Thunderbolt changes for 6.18-rc1 2025-10-04 16:07:08 -07:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Just one series here - Mike Rappoport has taught KEXEC handover to 2025-10-11 10:27:52 -07:00
Makefile Linux 6.18-rc1 2025-10-12 13:42:36 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.