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 AB0F12AEE1; Sat, 6 Jun 2026 00:36:36 +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=1780706197; cv=none; b=dQZuTMOXuCRvLMDermwcUk4t9mafX/A0cOmBJ8xLJxF+AYf+CDADKgBZWeys6+7r8F//6ZlDFnpYFtBIua6sF9ZZg9SThFTqKjpAFxyrOCOj+0CnD8E/MGXWhMxAmL2YRyj93a0m0Cadypgp/mXgaG/mSje1peiuvV3rHmPrDrw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780706197; c=relaxed/simple; bh=xPJpsk4fCWhHFLotY9Z+aG2/WSNeKHLmHOP0NM+HU2A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JFWNZTePXhFTzJ7NnuodbxRMqjIf+oCmaxBsOTS1wP6q/4keSTOdCH9B4L6c2gKSa8zr55Pr7hLUAWlUuevWk0qat2Vf/l4QkELpC5xD/RKUzzcbNMDlNJgK3s976JIg984NQ2oqnPJThGvfd0j2TR8QOPtFYniW8oEqJQtr06s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fw/vLaTX; 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="Fw/vLaTX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16C481F00893; Sat, 6 Jun 2026 00:36:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780706196; bh=if7f2i827CYYs4L2MWjOunPYSfsBUmgkGAdZ7VFnG54=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Fw/vLaTXL6yirNSzNZu4/QAtzAszDN+U36IQdoYEJdWbuAk6oju9WLGXzn9xi1DvV sedxmaFJCY7H4ijFitBnuhKd4PYgEsKAwWwuOAWB/cVZ1T9tr0gbefFIDE6qZ6X28J PfH5zCrVAQte3BUWNF58USZTO9D8Z/qtLNORH61oX6wXpcTd6PgroQj2Vz38GAVqWf hoen9t5E9ArWsx21uZevAez1HHKtHY9uQFKSP9j77izBeZZ0t6YOEU/jSrFSCPHzNK JopifGHCD99GzXSM0UHfQ+asewWGBkQzzLvXqwb4VSZC9JA1hvxaiggSXWpnZmbjFh nRbrhGpiyUg9g== From: SeongJae Park To: Sailesh Nandanavanam Cc: SeongJae Park , shuah@kernel.org, damon@lists.linux.dev, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] selftests/damon: add regression test for damos_walk() vs kdamond exit race Date: Fri, 5 Jun 2026 17:36:27 -0700 Message-ID: <20260606003627.88973-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, 5 Jun 2026 12:44:50 +0530 Sailesh Nandanavanam wrote: > Hi SeongJae, > > Apologies for the delayed response. No worry! [...] > I agree that a KUnit test is the right approach since it runs inside the > kernel and can directly set walk_control_obsolete to simulate the race > condition reliably without timing dependencies. > > I will drop the userspace selftest approach and write a KUnit test for > damos_walk() functionality including walk_control_obsolete. I will verify > it fails on a kernel with commit 33c3f6c2b48c ("mm/damon/core: fix > damos_walk() vs kdamond_fn() exit race") reverted and passes with the fix > present before sending v3. > > Regarding other feedback: > - Will use correct commit description format with subject in brackets > - Will remove the Fixes: tag > - Will add blank line before _damon_sysfs import > - Will add changelog and link previous versions > - Will share revision plan and wait at least one day > before sending new version Sounds good. Please consider using in-line reply [1] from the next time, though! > > Please give me some time to study mm/damon/tests/core-kunit.h and implement > this properly. No rush, take your time. [1] https://subspace.kernel.org/etiquette.html#do-not-top-post-when-replying Thanks, SJ [...]