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 6B7CC17E4; Sun, 16 Feb 2025 19:06:39 +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=1739732799; cv=none; b=r/UVHvm/f7oAx0I6g/Q/L6oOw9TJHh1BPBIwWwFFb+Pj5DNvuEpX0AfHkCJtguBK5DuKAN/Bpu2YbQQF/s8Kd99nC2wczG1pRv7nOkxxCik3Jv6Nh/9fOidPBg/O06hpXtngfewvy8xoTL8t72O/VEa645qFO66eoqeubUZnAHs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739732799; c=relaxed/simple; bh=O7NSxWzoeuFuIw1UPCPgZKMMHrar2/KGCtVfAJv3L4k=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=jgj8tG4vjPVh2iD1HiIKgg9wrprMQcOCr9KOlFXKw71INwMmS9fAfMvwkk1IHzAq4tPKHTCmksIvZzK2ZsJNdlD0OcRjpNOtg9bJvENHm2tK3sM5edXKKJH+sLlKXQ1hQ2toi6eJJIf60W/K0HsC4vFBygnYoFMDTs09+TSe7oQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Jd84Zb3U; 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="Jd84Zb3U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3D7DC4CEDD; Sun, 16 Feb 2025 19:06:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739732798; bh=O7NSxWzoeuFuIw1UPCPgZKMMHrar2/KGCtVfAJv3L4k=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Jd84Zb3UF85llvUO8w/ChFisdlVk2JJiY4XicELTLblzQ0oTaMnn6JaMT7FkaaYAM BGikJ/njek2u+/qQ5XFs4YixT/ZpzZKjcH8FW2KUGM67M42DXTDQ3aJ4FDzzdjatRP xB00eyFHBfFBR7rljQRNrTj0SQRNQctdwzDT+P7IVLjbRnbgEEfh3FEfWplAD1wCdU JWVnKgIvm3xmMgMYmaGV3s2FbbS6aYYDj3RcDITQw6IXB1CW3tkHsVnuTVj4QuQYSm QmYX3FwZ00QjDODkWtBxvKHX2SjaqVefQFuS9aT8VTkbJLqMeQghiFObEBZC+q7rgv QHEwEZSIYurRw== Received: from sofa.misterjones.org ([185.219.108.64] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1tjjyO-004cDp-Cp; Sun, 16 Feb 2025 19:06:36 +0000 Date: Sun, 16 Feb 2025 19:06:36 +0000 Message-ID: <87pljh1zgj.wl-maz@kernel.org> From: Marc Zyngier To: luoyonggang@gmail.com Cc: Oliver Upton , Sebastian Ott , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Shameer Kolothum , Cornelia Huck , Eric Auger , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/4] KVM: arm64: Allow userspace to change MIDR_EL1 In-Reply-To: References: <20250211143910.16775-1-sebott@redhat.com> <20250211143910.16775-2-sebott@redhat.com> <87v7tb17os.wl-maz@kernel.org> <86jz9psqwd.wl-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.4 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: luoyonggang@gmail.com, oliver.upton@linux.dev, sebott@redhat.com, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, shameerali.kolothum.thodi@huawei.com, cohuck@redhat.com, eric.auger@redhat.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Sun, 16 Feb 2025 18:55:23 +0000, "=E7=BD=97=E5=8B=87=E5=88=9A(Yonggang Luo)" wrote: >=20 > On Mon, Feb 17, 2025 at 2:09=E2=80=AFAM Marc Zyngier wro= te: > > > > On Sat, 15 Feb 2025 19:04:20 +0000, > > "=E7=BD=97=E5=8B=87=E5=88=9A(Yonggang Luo)" wro= te: > > > > > > According to this, the MIDR EL1 is updated properly, but the MIDR for > > > aarch32 is not updated, and I don't know how to hook the update for > > > MIDR for aarch32 > > > > It is the same thing. The AArch32 view is configured the same way as > > the AArch64 view, and there is nothing to do at all (that's what > > VPIDR_EL2 is all about). > > > > With Oliver's change, I'm correctly getting a different MIDR using a > > hacked up kvmtool, see below. I suspect you're not running with the > > correct patch applied. > > > The applied patch is V2, with writing vpidr_el2 disabled, Is that the cau= se? > The branch is here > https://github.com/lygstate/linux/tree/main > I am not applying your patch Well, there is no magic. If you don't write to VPIDR_EL2, not much will happen. You need to apply Oliver's change instead of the first patch in this series. M. --=20 Without deviation from the norm, progress is not possible.