You can build a user-space test program for the raid6 library code,
like this:
$ cd lib/raid6/test
$ make
The command in $(shell ...) function is evaluated by /bin/sh by default.
(or, you can specify the shell by passing SHELL=<shell> from command line)
Currently '>&/dev/null' is used to sink both stdout and stderr. Because
this code is bash-ism, it only works when /bin/sh is a symbolic link to
bash (this is the case on RHEL etc.)
This does not work on Ubuntu where /bin/sh is a symbolic link to dash.
I see lots of
/bin/sh: 1: Syntax error: Bad fd number
and
warning "your version of binutils lacks ... support"
Replace it with portable '>/dev/null 2>&1'.
Fixes: 4f8c55c5ad ("lib/raid6: build proper files on corresponding arch")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
06bd48b6cd