From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 491DE382F1A for ; Mon, 1 Jun 2026 07:00:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780297219; cv=none; b=AG0j/3ElKxZ4FqWYnPUg3atlV2vQX/g6cTGyhlwbk8xDtPi+U0JX9jgdgfmXhd4Pcf10KKXbIO5SqOo9eUHzXG5pTd6Bmn/fv8TR55o8cUR3YxRciO4h5mu8POEHAj6OUdXRORoZPKCHYg6RvSeP8qaw0d6HN4dloZWts3KCjKs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780297219; c=relaxed/simple; bh=2mdTE+Vya8utvQnMUqEZomtxNtoxxF5Hr1xqWCgH5cE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eFjYBFPf005eUrisiMRdDc4EIE3bAappBRtFPDVrE7xDu99iucm62P4mYVipZq+BrN9WJW1wpz5mOx4TCdTmNLXyc1vtPNpCFUDpPt97lXOxxeoTIwz3m8mUKGCPHTjAkmBaNKjWo5sml6S2Uda+nhpGoQ6si+eJxo0fuLignIo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PhLYx2Wu; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PhLYx2Wu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A12161F00893; Mon, 1 Jun 2026 07:00:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780297212; bh=sG16cqjI7FhoaRWQp7sfIsmBPD55jpILyYPNhzH0HJM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=PhLYx2Wu8AgTfIz+jj0OOGnKXyOUYFMO3olfikldAJMNFROAGoFnSULgR+6dK0TU7 viL3jQ7WOK2r7TEvDxUsJaz7URycqhGazOzUqppWDH13wwUjO/llcMYRMbXOsRR+mf ZwtYjWfIJWhx4t1ci56omI7yOOP3g39irVqlNA+ZDkrsqdeZQmCnMHVj03vx+eVVBZ lEy/HQoSI2vKDGlObWJaPri3DRUxUTiHZaPykrpML67YpTk7622Dmvloewu9DQIfEI tKqvElZXCO+sU2Xt1dEAGvcoruBnDPNRwhJZR0r2i1t/cUhLtOHLn2pP68JB87oBFs yLl3d/zUPTkCw== Date: Mon, 1 Jun 2026 10:00:05 +0300 From: Mike Rapoport To: Samiullah Khawaja Cc: Pasha Tatashin , Pratyush Yadav , Alexander Graf , David Matlack , open list , "open list:KEXEC HANDOVER (KHO)" , "open list:KEXEC HANDOVER (KHO)" Subject: Re: [PATCH v2 0/3] kho: Add support for kunit mocking KHO restore API Message-ID: References: <20260521193202.746810-1-skhawaja@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260521193202.746810-1-skhawaja@google.com> Hi Samiullah, On Thu, May 21, 2026 at 07:31:59PM +0000, Samiullah Khawaja wrote: > To write kunit tests for preservation and restoration of liveupdate > state in various subsystems without triggering the actual kexec, the KHO > restore API needs to be mocked by the test writer. The mocking is done > to allow testing of the individual components or functions in isolation. > > The patch series adds the following to support kunit testing when using the KHO > API: > > - Add static stub hooks to mock the KHO restore API so the restore path > can be tested without triggering kexec. > - Add helper function that can be used by the test writer to check if > memory is preserved in KHO tree. > > Finally, it adds a KUnit test for the KHO API that verifies the allocation of > preserved memory, and the preservation/restoration of pages and folios. I looked at the tests for preservation and apparently they don't add coverage beyond the existing KHO selftest. How hard and/or intrusive would be adding tests for example for error paths? Do you have an example of a kunit test for another subsystem that would benefit from mocking of KHO APIs? > KHO Kunit test run: > > KTAP version 1 > 1..1 > KTAP version 1 > # Subtest: kho_test > # module: kexec_handover_test > 1..3 > ok 1 kho_test_alloc_preserve > ok 2 kho_test_preserve_pages > ok 3 kho_test_preserve_folio > # kho_test: pass:3 fail:0 skip:0 total:3 > # Totals: pass:3 fail:0 skip:0 total:3 > ok 1 kho_test > > v2: > - Move kunit header includes above linux header includes. > - Use the __kho_preserve_pages_order() to get the order of preserved > pages instead of open order calculation math. > > Samiullah Khawaja (3): > kho: Add kunit static stubs > kho: Add helper function to check if pages are preserved > kho: Add kunit test to verify preserve/restore pages and folio > > include/linux/kexec_handover.h | 5 + > kernel/liveupdate/Kconfig | 10 ++ > kernel/liveupdate/Makefile | 1 + > kernel/liveupdate/kexec_handover.c | 63 +++++++++++- > kernel/liveupdate/kexec_handover_test.c | 131 ++++++++++++++++++++++++ > 5 files changed, 209 insertions(+), 1 deletion(-) > create mode 100644 kernel/liveupdate/kexec_handover_test.c > > > base-commit: ec4084bc445027a52f600e30a976928be1ba1950 > -- > 2.54.0.746.g67dd491aae-goog > -- Sincerely yours, Mike.