From: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
I honestly have no idea if this is sane.
This all came up in the context of increasing COMMAND_LINE_SIZE in the
RISC-V port. In theory that's a UABI break, as COMMAND_LINE_SIZE is the
maximum length of /proc/cmdline and userspace could staticly rely on
that to be correct.
Usually I wouldn't mess around with changing this sort of thing, but
PowerPC increased it with a5980d064fe2 ("powerpc: Bump COMMAND_LINE_SIZE
to 2048"). There are also a handful of examples of COMMAND_LINE_SIZE
increasing, but they're from before the UAPI split so I'm not quite sure
what that means: e5a6a1c90948 ("powerpc: derive COMMAND_LINE_SIZE from
asm-generic"), 684d2fd48e71 ("[S390] kernel: Append scpdata to kernel
boot command line"), 22242681cff5 ("MIPS: Extend COMMAND_LINE_SIZE"),
and 2b74b85693c7 ("sh: Derive COMMAND_LINE_SIZE from
asm-generic/setup.h.").
It seems to me like COMMAND_LINE_SIZE really just shouldn't have been
part of the UABI to begin with, and userspace should be able to handle
/proc/cmdline of whatever length it turns out to be. I don't see any
references to COMMAND_LINE_SIZE anywhere but Linux via a quick Google
search, but that's not really enough to consider it unused on my end.
I couldn't think of a better way to ask about this then just sending the
patch.
Signed-off-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
---
include/{uapi => }/asm-generic/setup.h | 0
1 file changed, 0 insertions(+), 0 deletions(-)
rename include/{uapi => }/asm-generic/setup.h (100%)
diff --git a/include/uapi/asm-generic/setup.h b/include/asm-generic/setup.h
similarity index 100%
rename from include/uapi/asm-generic/setup.h
rename to include/asm-generic/setup.h
--
2.31.1.498.g6c1eba8ee3d-goog
