[Qemu-devel] update-linux-headers.sh fails on clean kernel dir

[Sam Bobroff]

Hi QEMU developers,

If I run scripts/update-linux-headers.sh from a clean checkout of QEMU
and point it at a clean checkout of a recent linux kernel (4.10-rc1 or
later), it fails:

$ scripts/update-linux-headers.sh ~/tmp/linux/

...

scripts/Makefile.headersinst:62: *** Missing generated UAPI file 
./arch/arm/include/generated/uapi/asm/unistd-common.h.  Stop.

This seems to be because the script passes the arch to the kernel
makefile using "SRCARCH" rather than "ARCH".

(SRCARCH seems to be intended as an internal value, and setting it does
not propagate the setting to ARCH. Because ARCH is left empty, the
prerequisites that should generate unistd-common.h fail. If ARCH is set,
SRCARCH is set automatically and everything works.)

Changing the script to use "ARCH" seems to fixe the problem.

(Note: when testing this be careful: unistd-common.h is not removed by
"make clean" in the kernel directory.)

Does this seem correct?

Should I send a patch even though it's a very small change?

Cheers,
Sam.