From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05BDEEB64DC for ; Sun, 25 Jun 2023 22:15:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229447AbjFYWPX (ORCPT ); Sun, 25 Jun 2023 18:15:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229481AbjFYWPX (ORCPT ); Sun, 25 Jun 2023 18:15:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5BD5B1A5; Sun, 25 Jun 2023 15:15:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E425A60C36; Sun, 25 Jun 2023 22:15:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FB72C433C8; Sun, 25 Jun 2023 22:15:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687731321; bh=zFVqf7YtgUM3F6YoG2jfwFRTpf8aCuPZPnbOJyql7oI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bQWu/HyKwTHQmtgf357NogYhBahDyKX/1Jq6bAgM+m5Zo0iIokkBH1XRXky1qGyTg uhh/B3cij7HKHv6wOBpA1EIG7B7lJOwbtcF9DL+wB1dGlsyY0Y4KH2k3FMhDsD0Zdp Pn8HmbNqw7tdCXJwlcpp8V93ig8iSQeuR+sLgGmvggdJin3HEI7nGX87enlMtneFYB y/G6dMiGUgR+ur1R/E3W2GNtynrPGKnRxw2vgUCI3Wd2hQEH4nr9MThyP3fkw7MTL3 JSDxPlPcZr0FbpqthgqTPF0Scgq6omh6MWCAAVAQHMXae1H0A3BM9QG37PlVjR9k8p KNqe3j4L3WizQ== Date: Sun, 25 Jun 2023 23:15:14 +0100 From: Conor Dooley To: Song Shuai Cc: paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, robh+dt@kernel.org, frowand.list@gmail.com, ajones@ventanamicro.com, alexghiti@rivosinc.com, mpe@ellerman.id.au, arnd@arndb.de, rppt@kernel.org, samuel@sholland.org, panqinglin2020@iscas.ac.cn, conor.dooley@microchip.com, anup@brainfault.org, xianting.tian@linux.alibaba.com, anshuman.khandual@arm.com, heiko@sntech.de, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH V1 1/3] Revert "RISC-V: mark hibernation as nonportable" Message-ID: <20230625-obstinate-grimy-b765a1d3d741@spud> References: <20230625140931.1266216-1-songshuaishuai@tinylab.org> <20230625140931.1266216-2-songshuaishuai@tinylab.org> <20230625-multiple-diaper-1db88a75314e@spud> <20281f01-2cc9-892e-beea-eb2bb91e3ca5@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="6ZfynoZLMeCQs+ZJ" Content-Disposition: inline In-Reply-To: <20281f01-2cc9-892e-beea-eb2bb91e3ca5@gmail.com> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org --6ZfynoZLMeCQs+ZJ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hey, On Sun, Jun 25, 2023 at 11:09:21PM +0800, Song Shuai wrote: > Sorry for the delayed reply, It wasn't really delayed at all actually, you replied within an hour or so, AFAICT. > My tinylab email went something wrong, I'll use gmail in this thread. >=20 > =E5=9C=A8 2023/6/25 22:18, Conor Dooley =E5=86=99=E9=81=93: > > On Sun, Jun 25, 2023 at 10:09:29PM +0800, Song Shuai wrote: > > > This reverts commit ed309ce522185583b163bd0c74f0d9f299fe1826. > > >=20 > > > With the commit 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the > > > linear mapping") reverted, the MIN_MEMBLOCK_ADDR points the kernel > > > load address which was placed at a PMD boundary. > >=20 > > > And firmware always > > > correctly mark resident memory, or memory protected with PMP as > > > per the devicetree specification and/or the UEFI specification. > >=20 > > But this is not true? The versions of OpenSBI that you mention in your > > cover letter do not do this. > > Please explain. > >=20 >=20 > At this time, OpenSbi [v0.8,v1.3) and edk2(RiscVVirt) indeed don't obey t= he > DT/UEFI spec. This statement is excerpted from "Reserved memory for resid= ent > firmware" part from the upcoming riscv/boot.rst. It isn't accurate for no= w. > How about deleting this one? It is incorrect, so it will need to be removed, yes. Unfortunately writing a doc does not fix the existing implementations :( > Actually with 3335068f8721 reverted, the change of MIN_MEMBLOCK_ADDR can > avoid the mapping of firmware memory, I will make it clear in the next > version. To be honest, I'd like to see this revert as the final commit in a series that deals with the problem by actually reserving the regions, rather than a set of reverts that go back to how we were. I was hoping that someone who cares about hibernation support would be interested in working on that - *cough* starfive *cough*, although maybe they just fixed their OpenSBI and moved on. If there were no volunteers, my intention was to add a firmware erratum that would probe the SBI implementation & version IDs, and add a firmware erratum that'd parse the DT for the offending regions and reserve them. Cheers, Conor. > > > So those regions will not be mapped in the linear mapping and they > > > can be safely saved/restored by hibernation. > > >=20 > > > Signed-off-by: Song Shuai > > > --- > > > arch/riscv/Kconfig | 5 +---- > > > 1 file changed, 1 insertion(+), 4 deletions(-) > > >=20 > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > index 5966ad97c30c..17b5fc7f54d4 100644 > > > --- a/arch/riscv/Kconfig > > > +++ b/arch/riscv/Kconfig > > > @@ -800,11 +800,8 @@ menu "Power management options" > > > source "kernel/power/Kconfig" > > > -# Hibernation is only possible on systems where the SBI implementati= on has > > > -# marked its reserved memory as not accessible from, or does not run > > > -# from the same memory as, Linux > > > config ARCH_HIBERNATION_POSSIBLE > > > - def_bool NONPORTABLE > > > + def_bool y > > > config ARCH_HIBERNATION_HEADER > > > def_bool HIBERNATION > > > --=20 > > > 2.20.1 > --6ZfynoZLMeCQs+ZJ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZJi8cgAKCRB4tDGHoIJi 0gQGAP4zFRf+mJ/qW1QVdbXhgxrDoXAjwnQiAGH8Qr85iJdixAEAoUq/DIivnRJ8 mJWf9t+LoW93pFfGCZD7UXny7Skemgg= =Ztmn -----END PGP SIGNATURE----- --6ZfynoZLMeCQs+ZJ--