Re: [PATCH v2 2/4] osdep: Make qemu_madvise() return ENOSYS on unsupported OSes

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 31/5/24 09:53, David Hildenbrand wrote:
> On 31.05.24 09:28, Michal Privoznik wrote:
>> Not every OS is capable of madvise() or posix_madvise() even. In
>> that case, errno should be set to ENOSYS as it reflects the cause
>> better. This also mimic what madvise()/posix_madvise() would
>> return if kernel lacks corresponding syscall (e.g. due to
>> configuration).
> 
> Yes and no. According to the man page
> 
> " EINVAL advice is not a valid."
> 
> if a particular MADV_* call is not implemented, we would get EINVAL, 
> which is really unfortunate ... to detect what is actually supported :(

Maybe skip "This also mimic what madvise()/posix_madvise()
would return if kernel lacks corresponding syscall (e.g. due
to configuration)." for clarity?

> For the patch here ENOSYS makes sense:
> 
> Reviewed-by: David Hildenbrand <david@redhat.com>
>