On Wed, Mar 14, 2018 at 01:13:14PM +0100, Thierry Reding wrote: > On Wed, Mar 14, 2018 at 01:06:11PM +0100, Arnd Bergmann wrote: > > On Wed, Mar 14, 2018 at 12:45 PM, Thierry Reding > > <thierry.reding@xxxxxxxxx> wrote: > > > On Tue, Mar 13, 2018 at 12:52:05PM +0100, Arnd Bergmann wrote: > > >> Building the tegra PCIe host driver without MSI results in a link > > >> failure: > > >> > > >> drivers/pci/host/pci-tegra.o:(.data+0x70): undefined reference to `pci_msi_unmask_irq' > > >> drivers/pci/host/pci-tegra.o:(.data+0x74): undefined reference to `pci_msi_mask_irq' > > >> > > >> This adds the same dependency that everyone else uses. > > >> > > >> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> > > >> --- > > >> drivers/pci/host/Kconfig | 1 + > > >> 1 file changed, 1 insertion(+) > > > > > > I'm slightly concerned about the dependency. Not that I doubt its > > > correctness, but because it could mean that PCI_TEGRA is not visible in > > > the default configuration. The only reason why it is currently visible > > > is because PCI_MSI is selected by some symbols that also happen to be > > > enabled. However, what if at some point those symbols are disabled or > > > removed? > > > > > > Some architectures make sure that PCI_MSI is enabled by selecting it, > > > but that's risky, isn't it, because PCI_MSI is user-visible and could > > > therefore easily lead to conflicts. > > > > > > Enabling PCI_MSI in the arm64 defconfig would solve the issue and is > > > good enough for me. I've got a couple of changes to that defconfig in > > > the Tegra tree for v4.17-rc1, I can add a patch to enable PCI_MSI. > > > > > > Unless there are any objections. > > > > I looked at it again and found that this on ARM64, PCI_MSI is always > > selected indirectly by ARM_GIC&&PCI, so there is no problem. > > > > The build failure must have been on 32-bit ARM. > > Okay, I had assumed that ARM_GIC_V2M (which selects PCI_MSI) was user- > visible and hence could be disabled. But it's not, and always enabled on > ARM64. On 32-bit we already explicitly enable PCI_MSI via the default > configurations. > > I withdraw my concerns. I see that Lorenzo already applied the patch, so > just for the record: Apologies - it fixed an issue and it seemed harmless hence I applied it straight away, I should have waited for an ACK. > Acked-by: Thierry Reding <treding@xxxxxxxxxx> Updated - it is important to keep records, that's what tags are for. Thanks, Lorenzo
