[+cc sparc folks, PCI enumeration via OF likely broken] On Tue, Feb 17, 2026 at 11:15:26PM +0530, Nilay Shroff wrote: > Recent changes [1] replaced the use of no_64bit_msi with msi_addr_mask. > As a result, msi_addr_mask is now expected to be initialized to > DMA_BIT_MASK(64) when a pci_dev is set up. However, this initialization > was missed on powerpc due to differences in the device initialization > path compared to other architectures. Due to this, now pci device probe > method fails on powerpc system.
s/pci/PCI/ to match below. > On powerpc systems, struct pci_dev instances are created from device > tree nodes via of_create_pci_dev(). Because msi_addr_mask was not > initialized there, it remained zero. Later, during MSI setup, > msi_verify_entries() validates the programmed MSI address against > pdev->msi_addr_mask. Since the mask was not set correctly, the > validation fails, causing PCI driver probe failures for devices on > powerpc systems. > > Initialize pdev->msi_addr_mask to DMA_BIT_MASK(64) in > of_create_pci_dev() so that MSI address validation succeeds and device > probe works as expected. > > [1] > https://lore.kernel.org/all/[email protected]/ > > Fixes: 386ced19e9a3 ("PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA > address mask") > Signed-off-by: Nilay Shroff <[email protected]> Looks like this and a similar sparc fix need to be in v7.0. Would be great if they could make v7.0-rc1 (Sunday), but that's pretty close. Thomas, you merged 386ced19e9a3. I'm happy to merge the powerpc and sparc fixes, given acks from you and the powerpc & sparc folks, or feel free to take them yourself. > --- > arch/powerpc/kernel/pci_of_scan.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/powerpc/kernel/pci_of_scan.c > b/arch/powerpc/kernel/pci_of_scan.c > index 756043dd06e9..26ec97ce6b40 100644 > --- a/arch/powerpc/kernel/pci_of_scan.c > +++ b/arch/powerpc/kernel/pci_of_scan.c > @@ -211,6 +211,12 @@ struct pci_dev *of_create_pci_dev(struct device_node > *node, > dev->current_state = PCI_UNKNOWN; /* unknown power state */ > dev->error_state = pci_channel_io_normal; > dev->dma_mask = 0xffffffff; It's typical to add a blank line between the code above and the comment below, as was done in 386ced19e9a3. > + /* > + * Assume 64-bit addresses for MSI initially. Will be changed to 32-bit > + * if MSI (rather than MSI-X) capability does not have > + * PCI_MSI_FLAGS_64BIT. Can also be overridden by driver. > + */ > + dev->msi_addr_mask = DMA_BIT_MASK(64); > > /* Early fixups, before probing the BARs */ > pci_fixup_device(pci_fixup_early, dev); > -- > 2.52.0 >
