On Wed, 22 Oct 2025, Geert Uytterhoeven wrote: > On Tue, 21 Oct 2025 at 13:54, Ilpo Järvinen > wrote: > > On Tue, 21 Oct 2025, Geert Uytterhoeven wrote: > > > On Mon, 20 Oct 2025 at 18:20, Ilpo Järvinen > > > wrote: > > > > On Mon, 20 Oct 2025, Geert Uytterhoeven wrote: > > > > > On Fri, 10 Oct 2025 at 16:42, Ilpo Järvinen > > > > > wrote: > > > > > > 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() > > > > > > > > > > Thanks for your series! > > > > > > > > > > I have applied this on top of commit 06b77d5647a4d6a7 ("PCI: > > > > > Mark resources IORESOURCE_UNSET when outside bridge windows"), and > > > > > gave it a a try on Koelsch (R-Car M2-W). > > > > > > > > So the pci_bus_add_resource() patch to rcar_pci_probe() was not included? > > > > No coalescing would be attempted without that change. > > > > > > Sorry, I didn't realize you wanted that (and anything else) to be > > > included, too. Please tell me the exact base I should use for testing, > > > and I will give it another run. > > > > I'm sorry, it's indeed a bit confusing as some of these patches never > > have been in Linus' tree. > > > > So I'm interested on what's the result with these changes/series together: > > > > [PATCH 1/2] PCI: Setup bridge resources earlier > > [PATCH 2/2] PCI: Resources outside their window must set IORESOURCE_UNSET > > [PATCH 1/1] PCI: rcar-gen2: Add BAR0 into host bridge resources > > [PATCH 1/3] PCI: Refactor host bridge window coalescing loop to use prev > > [PATCH 2/3] PCI: Do not coalesce host bridge resource structs in place > > [PATCH 3/3] resource, kunit: add test case for resource_coalesce() > > > > You might also want to change that pci_dbg() in the IORESOURCE_UNSET patch > > to pci_info() (as otherwise dyndbg is necessary to make it visible). > > Thanks, all done: > > $ git cherry -v --abbrev=1 v6.18-rc2^ > + 211ddde0 Linux 6.18-rc2 > + 3fdaf2 PCI: Setup bridge resources earlier > + 5be02e5 PCI: Resources outside their window must set IORESOURCE_UNSET > + adf6f11 PCI: rcar-gen2: Add BAR0 into host bridge resources > + eecb500 PCI: Refactor host bridge window coalescing loop to use prev > + 60470b3 PCI: Do not coalesce host bridge resource structs in place > + afe3ec resource, kunit: add test case for resource_coalesce() > + 487c98 Use dev_info() in drivers/pci/probe.c:__pci_read_base() > IORESOURCE_UNSET path > > Compared to v6.18-rc2, dmesg changed (for the first PCI/USB instance) > like: > > pci-rcar-gen2 ee090000.pci: host bridge /soc/pci@ee090000 ranges: > pci-rcar-gen2 ee090000.pci: MEM 0x00ee080000..0x00ee08ffff > -> 0x00ee080000 > pci-rcar-gen2 ee090000.pci: PCI: revision 11 > pci-rcar-gen2 ee090000.pci: PCI host bridge to bus 0000:00 > pci_bus 0000:00: root bus resource [bus 00] > pci_bus 0000:00: root bus resource [mem 0xee080000-0xee08ffff] > +pci_bus 0000:00: root bus resource [mem 0xee090000-0xee090bff] > pci 0000:00:00.0: [1033:0000] type 00 class 0x060000 conventional > PCI endpoint > pci 0000:00:00.0: BAR 0 [mem 0xee090800-0xee090bff] > -pci 0000:00:00.0: BAR 1 [mem 0x40000000-0x7fffffff pref] > +pci 0000:00:00.0: BAR 1 [mem 0x40000000-0x7fffffff pref]: no > initial claim (no window) > +pci 0000:00:00.0: BAR 1 [mem size 0x40000000 pref] > pci 0000:00:01.0: [1033:0035] type 00 class 0x0c0310 conventional > PCI endpoint > -pci 0000:00:01.0: BAR 0 [mem 0x00000000-0x00000fff] > +pci 0000:00:01.0: BAR 0 [mem 0x00000000-0x00000fff]: no initial > claim (no window) > +pci 0000:00:01.0: BAR 0 [mem size 0x00001000] > pci 0000:00:01.0: supports D1 D2 > pci 0000:00:01.0: PME# supported from D0 D1 D2 D3hot > pci 0000:00:02.0: [1033:00e0] type 00 class 0x0c0320 conventional > PCI endpoint > -pci 0000:00:02.0: BAR 0 [mem 0x00000000-0x000000ff] > +pci 0000:00:02.0: BAR 0 [mem 0x00000000-0x000000ff]: no initial > claim (no window) > +pci 0000:00:02.0: BAR 0 [mem size 0x00000100] > pci 0000:00:02.0: supports D1 D2 > pci 0000:00:02.0: PME# supported from D0 D1 D2 D3hot > PCI: bus0: Fast back to back transfers disabled > pci 0000:00:01.0: BAR 0 [mem 0xee080000-0xee080fff]: assigned > pci 0000:00:02.0: BAR 0 [mem 0xee081000-0xee0810ff]: assigned > pci_bus 0000:00: resource 4 [mem 0xee080000-0xee08ffff] > +pci_bus 0000:00: resource 5 [mem 0xee090000-0xee090bff] > pci 0000:00:01.0: enabling device (0140 -> 0142) > pci 0000:00:02.0: enabling device (0140 -> 0142) > > > The expected result is that those usb resources are properly parented and > > the ee080000-ee08ffff and ee090000-ee090bff are not coalesced together (as > > that would destroy information). So something along the lines of: > > > > ee080000-ee08ffff : pci@ee090000 > > ee080000-ee080fff : 0000:00:01.0 > > ee080000-ee080fff : ohci_hcd > > ee081000-ee0810ff : 0000:00:02.0 > > ee081000-ee0810ff : ehci_hcd > > ee090000-ee090bff : ee090000.pci pci@ee090000 > > Compared to v6.18-rc2, the output of "lspci -v" or "cat /proc/iomem" > did not change. Hence for the two PCI/USB instances: > > ee080000-ee08ffff : pci@ee090000 > ee080000-ee080fff : 0000:00:01.0 > ee080000-ee080fff : ohci_hcd > ee081000-ee0810ff : 0000:00:02.0 > ee081000-ee0810ff : ehci_hcd > ee090000-ee090bff : ee090000.pci pci@ee090000 > ee0c0000-ee0cffff : pci@ee0d0000 > ee0c0000-ee0c0fff : 0001:01:01.0 > ee0c0000-ee0c0fff : ohci_hcd > ee0c1000-ee0c10ff : 0001:01:02.0 > ee0c1000-ee0c10ff : ehci_hcd > ee0d0000-ee0d0bff : ee0d0000.pci pci@ee0d0000 Looks it works now when it comes to what PCI: Resources outside their window must set IORESOURCE_UNSET tried to achieve. Thanks a lot for all the testing! -- i.