From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 52FBE270553; Tue, 14 Oct 2025 21:30:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760477401; cv=none; b=BjIeUphUU0fQ8+A6nYz8Im5Vsk+D3lmeEF5AvVjTlBEQcprD5cGj+G5SUEmaupPBcSI1Ed9QukxSKG3g+lEJ0TbMdBW2Sze+9M9+DPDFEGTZgPtLCNDKgGPCqRq3fv4HOLf/TjuzHL/9S8S4UlhO5jMDRjCGmVBTIifefYBRpCM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760477401; c=relaxed/simple; bh=sz0RIab+uJDmAtx+yofP3RZAaWLPnwR8PIrrUTZ0djo=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=IO8zV+lTTidzW/dSnnvJ7GSILytkFPOxnW0ZUk1cTFc1yZqgZuBZ8/wuKeBQh46uEd6rkVppMLqG3Dn/ZBCFZO9Fh0kDohpcPU+WVzzr5BmztsFtvj0e1H98ugCdeatXBX+rvwm2bTikaKh6sxw3DhcN3UEYoT7wI5mzCEyKE9U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=zn8vuI9M; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="zn8vuI9M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EBDEC4CEE7; Tue, 14 Oct 2025 21:29:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1760477400; bh=sz0RIab+uJDmAtx+yofP3RZAaWLPnwR8PIrrUTZ0djo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=zn8vuI9MGoprYrCJqaLNdOcaMkWNA39uHSdnWX7pIlJsyEOgxQ9Jbu/CMR/HdS8QJ v6T2xsObYK/nuDBNmbUCj6PzyKt5Oye0QVOqWaU+eEe7jPALPSF0VeeEzVsPFhD8Gm JLyEF4e5x0eoYTFiLL69Ldcx8dpcDCZf+xFZeKSo= Date: Tue, 14 Oct 2025 14:29:57 -0700 From: Andrew Morton To: Itamar-Dalal Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, david@redhat.com, lorenzo.stoakes@oracle.com, riel@surriel.com, Liam.Howlett@oracle.com, vbabka@suse.cz, harry.yoo@oracle.com, jannh@google.com, rppt@kernel.org, surenb@google.com, mhocko@suse.com, shuah@kernel.org Subject: Re: [PATCH] Add a new test 'migrate.cow_after_fork' that verifies correct RMAP handling of Copy-On-Write pages after fork(). Before a write, parent and child share the same PFN; after a write, the =?UTF-8?B?Y2hp?= =?UTF-8?B?bGTigJlz?= PFN differs, confirming proper COW duplication. Message-Id: <20251014142957.4253f2fc62e9e49bfc4433ab@linux-foundation.org> In-Reply-To: <20251014194944.20341-1-dalalitamar@gmail.com> References: <20251014194944.20341-1-dalalitamar@gmail.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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=UTF-8 Content-Transfer-Encoding: 8bit On Tue, 14 Oct 2025 22:49:44 +0300 Itamar-Dalal wrote: > Subject: [PATCH] Add a new test 'migrate.cow_after_fork' that verifies correct RMAP handling of Copy-On-Write pages after fork(). Before a write, parent and child share the same PFN; after a write, the child’s PFN differs, confirming proper COW duplication. > Date: Tue, 14 Oct 2025 22:49:44 +0300 > X-Mailer: git-send-email 2.34.1 > > Signed-off-by: Itamar-Dalal > --- > tools/testing/selftests/mm/rmap.c | 45 ++++++++++++++++++++++++++++++- > 1 file changed, 44 insertions(+), 1 deletion(-) OK, somehow your changelog was pasted into the email Subject, so please resend. Please prefix the Subject: with something which tells readers what part of the kernel is affected. eg, : : Subject: selfstests/mm/rmap: verify correct RMAP handling of COW pages after fork() : Then enter the details in the changelog body, eg: : : Before a write, parent and child share the same PFN. After a write, the : child’s PFN differs. Check this to confirm proper COW duplication. :