On Tue, Jun 30, 2020 at 6:07 PM Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: > > On Tue, 30 Jun 2020 00:05:52 -0700 > David Gow <davidgow@xxxxxxxxxx> wrote: > > > The Analog Devices AXI ADC driver uses the devm_ioremap_resource > > function, but does not specify a dependency on IOMEM in Kconfig. This > > causes a build failure on architectures without IOMEM, for example, UML > > (notably with make allyesconfig). > > > > Fix this by making CONFIG_ADI_AXI_ADC depend on CONFIG_IOMEM. > > > > Signed-off-by: David Gow <davidgow@xxxxxxxxxx> > Hi David, > > Could you confirm what the build error is? I thought the stubs added in > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1bcbfbfdeb > were meant to allow us to avoid having lots of depends on IOMEM lines for the > few architectures who don't support it. No worries: /usr/bin/ld: drivers/iio/adc/adi-axi-adc.o: in function `adi_axi_adc_probe': torvalds-linux/drivers/iio/adc/adi-axi-adc.c:415: undefined reference to `devm_platform_ioremap_resource' Alas, the devm_platform_ioremap_resource function isn't handled by the UML stubs: it all seems to be in drivers/base/platform.c and lib/devres.c, behind #ifdef HAS_IOMEM. In any case, improving IOMEM support for UML (at least for the KUnit test case, which is my use case) is something I'd like to do. There are only three drivers[1,2] upstream at the moment which fail to build as-is, though, so it seemed worth trying to fix them in the meantime. That being said, I tried just getting rid of the few #ifdef HAS_IOMEMs around the various devm_*_ioremap functions, and everything seems to be working... So maybe that's a false dependency given the various stubs (at least on UML). I used this (hideously hacky) patch: diff --git a/drivers/base/platform.c b/drivers/base/platform.c index c0d0a5490ac6..b6f08c88e2b6 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -61,7 +61,7 @@ struct resource *platform_get_resource(struct platform_device *dev, } EXPORT_SYMBOL_GPL(platform_get_resource); -#ifdef CONFIG_HAS_IOMEM +#if 1//def CONFIG_HAS_IOMEM /** * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a * platform device and get resource diff --git a/lib/Makefile b/lib/Makefile index b1c42c10073b..35c21af33b93 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -115,7 +115,7 @@ obj-y += math/ crypto/ obj-$(CONFIG_GENERIC_IOMAP) += iomap.o obj-$(CONFIG_GENERIC_PCI_IOMAP) += pci_iomap.o -obj-$(CONFIG_HAS_IOMEM) += iomap_copy.o devres.o +obj-y += iomap_copy.o devres.o obj-$(CONFIG_CHECK_SIGNATURE) += check_signature.o obj-$(CONFIG_DEBUG_LOCKING_API_SELFTESTS) += locking-selftest.o --- If this seems to work more broadly, I may try to clean it up and post it for broader review. Cheers, -- David
