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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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d911202e3f
I think that it's better to detect DMA misuse at build time rather than calling BUG_ON. Architectures that can't do DMA need to define CONFIG_NO_DMA. Thanks to Sam Ravnborg for explaining how CONFIG_NO_DMA and CONFIG_HAS_DMA work: http://marc.info/?l=linux-kernel&m=128359913825550&w=2 HAS_DMA is defined like this: config HAS_DMA boolean depends on !NO_DMA default y So to set HAS_DMA to true an arch should do: 1) Do not define NO_DMA 2) Define NO_DMA abd set it to 'n' Must archs - including um - used principle 1). In the um case we want to say that we do NOT have any DMA. This can be done in two ways. a) define NO_DMA and set it to 'y' b) redefine HAS_DMA and set it to 'n'. The patch you provided used principle b) where other archs use principle a). So I suggest you should use principle a) for um too. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Jeff Dike <jdike@addtoit.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| kernel | ||
| os-Linux | ||
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| sys-i386 | ||
| sys-ia64 | ||
| sys-ppc | ||
| sys-x86_64 | ||
| .gitignore | ||
| defconfig | ||
| Kconfig.char | ||
| Kconfig.common | ||
| Kconfig.debug | ||
| Kconfig.net | ||
| Kconfig.rest | ||
| Kconfig.um | ||
| Kconfig.x86 | ||
| Makefile | ||
| Makefile-i386 | ||
| Makefile-ia64 | ||
| Makefile-os-Linux | ||
| Makefile-ppc | ||
| Makefile-skas | ||
| Makefile-x86_64 | ||