[PATCH 0/3] PCI & resource: Make coalescing host bridge windows safer

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

Hi,

Here's a series for Geert to test if this fixes the improper coalescing
of resources as was experienced with the pci_add_resource() change (I
know the breaking change was pulled before 6.18 main PR but I'd want to
retry it later once the known issues have been addressed). The expected
result is there'll be two adjacent host bridge resources in the
resource tree as the different name should disallow coalescing them
together, and therefore BAR0 has a window into which it belongs to.

Generic info for the series:

PCI host bridge windows were coalesced in place into one of the structs
on the resources list. The host bridge window coalescing code does not
know who holds references and still needs the struct resource it's
coalescing from/to so it is safer to perform coalescing into entirely
a new struct resource instead and leave the old resource addresses as
they were.

The checks when coalescing is allowed are also made stricter so that
only resources that have identical the metadata can be coalesced.

As a bonus, there's also a bit of framework to easily create kunit
tests for resource tree functions (beyond just resource_coalesce()).

Ilpo Järvinen (3):
  PCI: Refactor host bridge window coalescing loop to use prev
  PCI: Do not coalesce host bridge resource structs in place
  resource, kunit: add test case for resource_coalesce()

 drivers/pci/probe.c          |  26 +++----
 include/linux/ioport.h       |   5 ++
 include/linux/resource_ext.h |   3 +
 kernel/resource.c            | 139 ++++++++++++++++++++++++++++++++++-
 kernel/resource_kunit.c      | 121 ++++++++++++++++++++++++++++++
 5 files changed, 279 insertions(+), 15 deletions(-)


base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
-- 
2.39.5