Re: [PATCH v3 1/1] selftests: vm: add process_mrelease tests

[Christian Brauner <brauner@kernel.org>]

On Wed, May 18, 2022 at 01:43:16PM -0700, Suren Baghdasaryan wrote:
> Introduce process_mrelease syscall sanity tests which include tests
> which expect to fail:
> - process_mrelease with invalid pidfd and flags inputs
> - process_mrelease on a live process with no pending signals
> and valid process_mrelease usage which is expected to succeed.
> Because process_mrelease has to be used against a process with a pending
> SIGKILL, it's possible that the process exits before process_mrelease
> gets called. In such cases we retry the test with a victim that allocates
> twice more memory up to 1GB. This would require the victim process to
> spend more time during exit and process_mrelease has a better chance of
> catching the process before it exits and succeeding.
> 
> On success the test reports the amount of memory the child had to
> allocate for reaping to succeed. Sample output:
> 
> $ mrelease_test
> Success reaping a child with 1MB of memory allocations
> 
> On failure the test reports the failure. Sample outputs:
> 
> $ mrelease_test
> All process_mrelease attempts failed!
> 
> $ mrelease_test
> process_mrelease: Invalid argument
> 
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> ---

Thanks your adding selftests, Suren!
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>