From e5f72cb9cea599dc9f5a9b80a33560a1d06f01cc Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Tue, 10 Feb 2026 22:20:57 +0800 Subject: [PATCH] PCI: Validate window resource type in pbus_select_window_for_type() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit After ebe091ad81e1 ("PCI: Use pbus_select_window_for_type() during IO window sizing") and ae88d0b9c57f ("PCI: Use pbus_select_window_for_type() during mem window sizing"), many bridge windows can't get resources assigned: pci 0006:05:00.0: bridge window [??? 0x00001000-0x00001fff flags 0x20080000]: can't assign; no space pci 0006:05:00.0: bridge window [??? 0x00001000-0x00001fff flags 0x20080000]: failed to assign Those commits replace find_bus_resource_of_type() with pbus_select_window_for_type(), and the latter lacks resource type validation. Add the resource type validation back to pbus_select_window_for_type() to match the original behavior. Fixes: 74afce3dfcba ("PCI: Add bridge window selection functions") Link: https://bugzilla.kernel.org/show_bug.cgi?id=221072 Signed-off-by: Kai-Heng Feng Signed-off-by: Bjorn Helgaas Reviewed-by: Ilpo Järvinen Link: https://patch.msgid.link/20260210142058.82701-1-kaihengf@nvidia.com --- drivers/pci/setup-bus.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 32aa72456a44..f30d1f7f023a 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -224,14 +224,21 @@ static struct resource *pbus_select_window_for_type(struct pci_bus *bus, switch (iores_type) { case IORESOURCE_IO: - return pci_bus_resource_n(bus, PCI_BUS_BRIDGE_IO_WINDOW); + win = pci_bus_resource_n(bus, PCI_BUS_BRIDGE_IO_WINDOW); + if (win && (win->flags & IORESOURCE_IO)) + return win; + return NULL; case IORESOURCE_MEM: mmio = pci_bus_resource_n(bus, PCI_BUS_BRIDGE_MEM_WINDOW); mmio_pref = pci_bus_resource_n(bus, PCI_BUS_BRIDGE_PREF_MEM_WINDOW); - if (!(type & IORESOURCE_PREFETCH) || - !(mmio_pref->flags & IORESOURCE_MEM)) + if (mmio && !(mmio->flags & IORESOURCE_MEM)) + mmio = NULL; + if (mmio_pref && !(mmio_pref->flags & IORESOURCE_MEM)) + mmio_pref = NULL; + + if (!(type & IORESOURCE_PREFETCH) || !mmio_pref) return mmio; if ((type & IORESOURCE_MEM_64) || -- 2.47.3