From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794308597; b=BqHjYuHJiD5jqYr6D921D47QVVo0uIPv8RwrzNGEOa9J0LMqLgYLaO09O8CTYIPA5tHi pzaZ44AjS571i0hST1JoZ6R/7Fepvp73fsOJ1sdH8w0urMsUpYIsffzO94n4UdALB3pvh 0hJM4Fur3uZAW+C3XVQQaAVF/3pAsYnG++TlpYwBd3+cg7lMs0mH/Wu6IKvLiQD1jqjd1 GH8KmSdNwUKzS0BImMeT5IGzjOwMWCHTBNF+co4W3ZXzUIzDebmALxyUD/mkMPIbXBNZX /cvZa/MBRmdy9DWBpsshBOp7aYl6vyd0RtyPBSle45FTnBVR4rBrZJYy2h9lq1vEFgA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794308597; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=zJqoM5byy7t2oJnrolNTZNqtxc09Si1RLmF8E4lHkmc=; b=OMUthagpJbpQA05IhBFCf1R0ShiYdO5ccO17lKGsLiVJvlcxgTfMh7hXVek3PtTIVpBF jNukrc69y7tA7IurJy9Z02XJ2ylfByovKgUYfaFH7Q3Vyvdh8fzlK90vvrVirJHaemlrD 1Mt/sBcpm341E+ATccWzj0oGH5i/SpiPZjRdiemdhO1bTSfSDkHcWHrX8ilPl/RcbD7DV mLYPd9f9PNoGINqn+f9W96shmxftB5DCPAfqz0vIUFlP/+hA3oujvDdzoVDeI5F07EnWz snnQUpqt4y1IGttRX0MXLsUETLpVc63CwFPcFkIsbDP8JBLo0Zbxrky2nFWSde2uGag== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=YANA8zpl; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 97FEF606A31C; Tue, 10 Nov 2026 11:03:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=YANA8zpl Received: by smtp.kernel.org (Postfix) with ESMTPSA id 558691F008A1; Tue, 10 Nov 2026 11:03:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794308597; bh=zJqoM5byy7t2oJnrolNTZNqtxc09Si1RLmF8E4lHkmc=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=YANA8zplr5ixeJhh0AM8kWaDEpgWrinnTQE5LawdfgLFWTMxt5ac2dOiWa2uHAMWT ECRyCaV5UcHiP0DAo950O9Dmg0eiMieX5pblSLm5iCsk5XT3a9DATsrRof7z/6txrQ mwJ76n3z4xZHT0rB0l8oFErQFtc54rlSYNYJ5NS5nwj6xa1ameGYDGdHgXlRk/01r8 bZANPsfP8Swcja4QTEWwCPFJkEUzh7Fdsp5RiafyRFQLtUGpl5OvmRJugN4TQbo7/U Q/1lOVg0My+24NrLBHq5Z1LHUVmtllX3g3t3W6cC1YtpP7IgN0+ncBEq4UwiLL9fTs HUPvecaa/x0jA== Date: Tue, 10 Nov 2026 11:03:10 +0000 From: "Lorenzo Stoakes (ARM)" To: Seunghyun An Cc: linux-mm@kvack.org, Andrew Morton , David Hildenbrand , Vlastimil Babka , "Liam R . Howlett" , Jann Horn , Pedro Falcato , Matthew Wilcox , Jan Kara , Dave Hansen , Suren Baghdasaryan , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 0/2] mm: avoid redundant reads of the vm_refcnt cacheline in anonymous faults Message-ID: References: <20261110000002.1834454-1-san55@wisc.edu> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261110000002.1834454-1-san55@wisc.edu> Thanks for the report. You are a complete newcomer to mm, and you are sending very subtle changes to a core part of it, so I am not confident that you have the depth of understanding the kernel requires for such work. See https://docs.kernel.org/process/generated-content.html I'll therefore take over this change and treat this as a bug report. I will give you due credit for reporting the issue of course. I'd like to collaborate on the perf measurements however, so if you could re-run your test results on my series when I send it that'd be appreciated. In general it seems that the actual issue is the debug assertion, given you state only vma_has_anon_rmap() as a problem here. In general in future - while we're fine with you using LLMs, newcomers should work on small, incremental changes to mm to build up understanding first. -- Cheers, Lorenzo