Re: [PATCH net-next] docs: netdev: refine netdevsim testing guidance
From: Simon Horman <horms@kernel.org>
Date: 2026-03-06 14:39:08
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linux-doc, workflows
On Wed, Mar 04, 2026 at 07:16:46AM -0800, Jakub Kicinski wrote:
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. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- CC: corbet@lwn.net CC: skhan@linuxfoundation.org CC: workflows@vger.kernel.org CC: linux-doc@vger.kernel.org
Reviewed-by: Simon Horman <horms@kernel.org>
quoted hunk ↗ jump to hunk
--- Documentation/process/maintainer-netdev.rst | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)diff --git a/Documentation/process/maintainer-netdev.rst b/Documentation/process/maintainer-netdev.rst index 6bce4507d5d3..3aa13bc2405d 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.
I don't know if it's desirable, but the line wrapping could also be updated.
We give no guarantees that ``netdevsim`` won't change in the future -- 2.53.0