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 649921AF0CA for ; Thu, 30 Jan 2025 08:42:25 +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=1738226545; cv=none; b=B22+GlF6uoPIJ9/CK9bwGp1+HEgAudEiQbLZ9FLwVs/NjlJMLPdyQMktkqIb6M5p1uZlzwo9TjPvJm51XCMS3uEtOh9ifaKMN+USBgBPXAAFROVhR8dDM1i2910pWwE9WFuA/gd8pnEmbbCXgb95HxERZCQ+26MnsV3ykyncxHo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738226545; c=relaxed/simple; bh=Hns6xwQBsveKR1vKW31yktZyPYFYoDOUmz4ZKRbjlTo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=NBNvDWh3qfvviiN0mcMvUgBM4QwSkJU3nyKK/LDRsXVlYfGZJXKGBvr0UlC0OKBwzyAWiuB0G+zxU7k5ZSFGYXF69sf+Rb+sIy1u0MYYymwkpE6pyAaxKB2UInlKVvxUQchBl8c1wGuzw9OjuTgaRI7ZAkp3fCuRSCuneof3uT0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vMzj4MYK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vMzj4MYK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E7D8C4CED2; Thu, 30 Jan 2025 08:42:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738226544; bh=Hns6xwQBsveKR1vKW31yktZyPYFYoDOUmz4ZKRbjlTo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=vMzj4MYKtAiqJ6RLff4zJDABl7+halshmCh0EvHM/8X2HgrGzphOmm/IaTDLL2HEf p/9fD1tMNFp222OgdU2zOCRlhTlG1kDFeqYBoKW52i0oegKOaJ8nlfMprSIcYMsyW1 hwW7EUpyvJUayUv6fvRpQ1ViC3pJtLfUsXYSMuNMQyJ8gcKVZh04FkyCfRClMXX3Gk 1dIlONxzZo0i7Oe9+E5qtuou5p4mAtt/K2wF2pCxM+pe0jJT2VEL960qR8Q4l1yeew p96p4fQVsGo7jz/LkVhj4gAqLH3vvZbuA0bUSwt85euHZ8Uum/sFSH+zLERjXHR5xn 6PyU2iGEfGhdw== From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= To: Chunyan Zhang , Palmer Dabbelt , Albert Ou , Paul Walmsley , Alexandre Ghiti , Andrew Morton Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Chunyan Zhang , Alistair Popple , linux-mm@kvack.org Subject: Re: [PATCH V5 1/3] riscv: mm: Prepare for reusing PTE RSW bit(9) In-Reply-To: <20241113095833.1805746-2-zhangchunyan@iscas.ac.cn> References: <20241113095833.1805746-1-zhangchunyan@iscas.ac.cn> <20241113095833.1805746-2-zhangchunyan@iscas.ac.cn> Date: Thu, 30 Jan 2025 09:42:21 +0100 Message-ID: <87frl0snf6.fsf@all.your.base.are.belong.to.us> 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: quoted-printable Chunyan Zhang writes: > The PTE bit(9) on RISC-V is reserved for software, it is used by devmap > now which has to be disabled if we want to use bit(9) for other features, > since there's no more free PTE bit on RISC-V now. > > So to make ARCH_HAS_PTE_DEVMAP selectable, this patch uses it as > the build condition of devmap definitions. Heads-up: It seems like Alistair's series [1] that removes the devmap PTE bit will most likely land in 6.15. Bj=C3=B6rn [1] https://lore.kernel.org/linux-mm/cover.11189864684e31260d1408779fac9db8= 0122047b.1736488799.git-series.apopple@nvidia.com/