From: Jakub Kicinski Date: Wed, 4 Mar 2026 15:16:46 +0000 (-0800) Subject: docs: netdev: refine netdevsim testing guidance X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8e235bc43326f47adfd77d926c7d6ad39077569a;p=thirdparty%2Fkernel%2Flinux.git docs: netdev: refine netdevsim testing guidance The library to create tests for both NIC HW and netdevsim has existed for almost a year. netdevsim-only tests we get increasingly feel like a waste, we should try to write tests that work both on netdevsim and real HW. Refine the guidance accordingly. Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260304151647.2770466-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/Documentation/process/maintainer-netdev.rst b/Documentation/process/maintainer-netdev.rst index 6bce4507d5d31..3aa13bc2405d5 100644 --- a/Documentation/process/maintainer-netdev.rst +++ b/Documentation/process/maintainer-netdev.rst @@ -479,8 +479,14 @@ netdevsim ``netdevsim`` is a test driver which can be used to exercise driver configuration APIs without requiring capable hardware. -Mock-ups and tests based on ``netdevsim`` are strongly encouraged when -adding new APIs, but ``netdevsim`` in itself is **not** considered +Mock-ups and tests based on ``netdevsim`` are encouraged when +adding new APIs with complex logic in the stack. The tests should +be written so that they can run both against ``netdevsim`` and a real +device (see ``tools/testing/selftests/drivers/net/README.rst``). +``netdevsim``-only tests should focus on testing corner cases +and failure paths in the core which are hard to exercise with a real driver. + +``netdevsim`` in itself is **not** considered a use case/user. You must also implement the new APIs in a real driver. We give no guarantees that ``netdevsim`` won't change in the future