On 12/8/21 1:12 PM, Mark Brown wrote:
On Wed, Dec 08, 2021 at 11:59:18AM -0700, Shuah Khan wrote:
On 12/8/21 11:39 AM, Mark Brown wrote:
On Wed, Dec 08, 2021 at 10:42:35AM -0700, Shuah Khan wrote:
+ snd_ctl_elem_value_alloca(&val);
This is idiomatic for alsa-lib code.
This is kernel code that is going into kernel sources. Why follow
alsa-lib convention?
Well, the kernel doesn't generally use alloca() as a pattern given the
relatively small stack sizes we have and doesn't define helpers like
these for it... it's a toss up here between the conventions for use of
the library we're using and the conventions of the kernel.
+ ksft_print_header();
Add a check for root and skil the test.
There is no need for this test to run as root in most configurations,
it is common to provide direct access to the sound cards to some or all
users - for example with desktop distros the entire userspace audio
subsystem normally runs as the logged in user by default. alsa-lib's
On my system, I don't see any output if run as root. Are there some tests
that work as non-root?
All of them work as non-root if the user they're running as has access
to a card, if they do or not is system dependent - there may not be any
cards at all in a given system to find. Running as root will punch
through most permission problems but it's not a requirement and a system
could use a security module like SELinux to restrict what root can do.
The sound devices are usually in /dev/snd, though userspace can place
them where it wants - if run as a user that can access the relevant
devices for the mixer interface (usually /dev/snd/controlC* though again
userspace can rename them) then the tests will run on those devices.
Sounds good to me.
Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
thanks,
-- Shuah
