On 5/28/21 3:09 PM, Randy Dunlap wrote: > On 5/27/21 3:32 PM, Rob Herring wrote: >> Reserved memory regions can be used for more than just DMA regions, so >> only enabling on DMA_DECLARE_COHERENT (via HAS_DMA) or DMA_CMA is wrong. >> This effectively doesn't matter except for the few cases arches select >> NO_DMA. >> >> At least, these users of RESERVEDMEM_OF_DECLARE depend on reserved memory >> support: >> >> arch/riscv/mm/init.c:RESERVEDMEM_OF_DECLARE(elfcorehdr, "linux,elfcorehdr", elfcore_hdr_setup); >> drivers/memory/tegra/tegra210-emc-table.c:RESERVEDMEM_OF_DECLARE(tegra210_emc_table, "nvidia,tegra210-emc-table", >> drivers/soc/fsl/qbman/bman_ccsr.c:RESERVEDMEM_OF_DECLARE(bman_fbpr, "fsl,bman-fbpr", bman_fbpr); >> drivers/soc/fsl/qbman/qman_ccsr.c:RESERVEDMEM_OF_DECLARE(qman_fqd, "fsl,qman-fqd", qman_fqd); >> drivers/soc/fsl/qbman/qman_ccsr.c:RESERVEDMEM_OF_DECLARE(qman_pfdr, "fsl,qman-pfdr", qman_pfdr); >> >> Let's simplify things and enable OF_RESERVED_MEM when OF_EARLY_FLATTREE is >> enabled. >> >> Cc: Christoph Hellwig <hch@xxxxxx> >> Signed-off-by: Rob Herring <robh@xxxxxxxxxx> > > Hi Rob, > > I'm OK with this patch, but with or without this patch, > compiling kernel/dma/coherent.c without HAS_IOMEM (!) > has build errors: > > s390-linux-ld: kernel/dma/coherent.o: in function `dma_init_coherent_memory': > coherent.c:(.text+0x5ae): undefined reference to `memremap' > s390-linux-ld: coherent.c:(.text+0x7a4): undefined reference to `memunmap' > s390-linux-ld: kernel/dma/coherent.o: in function `dma_declare_coherent_memory': > coherent.c:(.text+0xd84): undefined reference to `memunmap' > > > along with a slew of other build errors (arch/s390/, CONFIG_PCI is not set, > CONFIG_HAS_IOMEM is not set): > > s390-linux-ld: drivers/irqchip/irq-al-fic.o: in function `al_fic_init_dt': > irq-al-fic.c:(.init.text+0x6a0): undefined reference to `iounmap' > s390-linux-ld: drivers/char/xillybus/xillybus_of.o: in function `xilly_drv_probe': > xillybus_of.c:(.text+0x2c8): undefined reference to `devm_platform_ioremap_resource' > s390-linux-ld: drivers/pcmcia/cistpl.o: in function `set_cis_map': > cistpl.c:(.text+0x87a): undefined reference to `ioremap' > s390-linux-ld: cistpl.c:(.text+0x99a): undefined reference to `iounmap' > s390-linux-ld: cistpl.c:(.text+0xa34): undefined reference to `iounmap' > s390-linux-ld: cistpl.c:(.text+0xaa6): undefined reference to `ioremap' > s390-linux-ld: drivers/pcmcia/cistpl.o: in function `release_cis_mem': > cistpl.c:(.text+0x2976): undefined reference to `iounmap' > s390-linux-ld: drivers/of/address.o: in function `of_iomap': > address.c:(.text+0x1f02): undefined reference to `ioremap' > s390-linux-ld: drivers/of/address.o: in function `of_io_request_and_map': > address.c:(.text+0x2030): undefined reference to `ioremap' > Oops, sorry. I should have said that this is also with my experimental path that I thought you suggested earlier this week (although I could have misunderstood you): --- linux-next-20210526.orig/drivers/of/Kconfig +++ linux-next-20210526/drivers/of/Kconfig @@ -64,7 +64,7 @@ config OF_DYNAMIC config OF_ADDRESS def_bool y - depends on !SPARC && (HAS_IOMEM || UML) + depends on !SPARC config OF_IRQ def_bool y [rebuild] OK, even without this small patch, the result is about the same (just a few different function names): s390-linux-ld: kernel/dma/coherent.o: in function `dma_init_coherent_memory': coherent.c:(.text+0x5ae): undefined reference to `memremap' s390-linux-ld: coherent.c:(.text+0x7a4): undefined reference to `memunmap' s390-linux-ld: kernel/dma/coherent.o: in function `dma_declare_coherent_memory': coherent.c:(.text+0xd84): undefined reference to `memunmap' s390-linux-ld: drivers/irqchip/irq-al-fic.o: in function `al_fic_init_dt': irq-al-fic.c:(.init.text+0x64): undefined reference to `of_iomap' s390-linux-ld: irq-al-fic.c:(.init.text+0x6a0): undefined reference to `iounmap' s390-linux-ld: drivers/char/xillybus/xillybus_of.o: in function `xilly_drv_probe': xillybus_of.c:(.text+0x2c8): undefined reference to `devm_platform_ioremap_resource' s390-linux-ld: drivers/pcmcia/cistpl.o: in function `set_cis_map': cistpl.c:(.text+0x87a): undefined reference to `ioremap' s390-linux-ld: cistpl.c:(.text+0x99a): undefined reference to `iounmap' s390-linux-ld: cistpl.c:(.text+0xa34): undefined reference to `iounmap' s390-linux-ld: cistpl.c:(.text+0xaa6): undefined reference to `ioremap' s390-linux-ld: drivers/pcmcia/cistpl.o: in function `release_cis_mem': cistpl.c:(.text+0x2976): undefined reference to `iounmap' >> --- >> This is needed to prevent build break on UML with this patch: >> >> https://lore.kernel.org/lkml/20210527193841.1284169-1-robh@xxxxxxxxxx/ >> >> drivers/of/Kconfig | 4 +--- >> 1 file changed, 1 insertion(+), 3 deletions(-) >> >> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig >> index 18450437d5d5..3dfeae8912df 100644 >> --- a/drivers/of/Kconfig >> +++ b/drivers/of/Kconfig >> @@ -75,9 +75,7 @@ config OF_NET >> def_bool y >> >> config OF_RESERVED_MEM >> - bool >> - depends on OF_EARLY_FLATTREE >> - default y if DMA_DECLARE_COHERENT || DMA_CMA >> + def_bool OF_EARLY_FLATTREE >> >> config OF_RESOLVE >> bool >> > > -- ~Randy
