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 586531DE4C9; Tue, 29 Jul 2025 15:47:05 +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=1753804025; cv=none; b=fgIyPyT/AW4jGFjahWjk5gLuLHJRKrneiRe59z41TFZ4Xt8+leKcqSty43aRt/v66IbstKx0LAvzgvPRyt8SoGNKAnSqtrCRFAmB25XgMpHN5cjRNtwYCELAblZ8ci06TZh1pOr4r/ikaRgOcJ6aO+O1UqAljdZb7OC+4jPDLLY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753804025; c=relaxed/simple; bh=asf759iARhCsqlW3LV9P1RiiwlEqeEAcEfX9/r8vZSU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jpnO2j+UP0vwQePE3ponFiOYJSv2idj8zO/cdt9NXPJ9KrkSR1RlMg7LsY05gKBGtJF91Zyv6wTz35sQgY3vtI/UXxb99ncc6aRTqs0xsK1q/Hk/AAMNhZIlTzusbtoyFX+jQ2N+MtkxM91SMD5xDJKCxP4vF2X38fsdbuU2hW0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=i2DgZaQS; 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="i2DgZaQS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CECC5C4CEEF; Tue, 29 Jul 2025 15:47:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753804024; bh=asf759iARhCsqlW3LV9P1RiiwlEqeEAcEfX9/r8vZSU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=i2DgZaQS6K3Vd6+mPAu9iGvuNRMCHZcr9QOs7zi3mtZ/f8s1gvwO0vy1CDZDba40p FDUoNHvYXjZNzwchfQuacmVUX75jrVU6vkEndnGuv0bhr8/y55eJXEdvkQQdFqJYcJ e7G98H90edHlHhCzx4/acrH+yRp2NHhVcvCPxvhiXrVpIUuW4KX4C28NUUs8lpcmtD 6WdKnq44DhRYOSKpjc0oQ7WPoc82VNIt/gP1mZNF3nVhDBnnLFxCegG/VbSeHuh9wd OUFr+mMfae87IM6Tf4X2Tv55W2L+++e7QbSYDrS3BRP6iuYnHBhrJdMrB1avRrO9IZ hiIGOLFkTQmHQ== Date: Tue, 29 Jul 2025 16:46:58 +0100 From: Will Deacon To: perlarsen@google.com Cc: Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Sudeep Holla , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, ahomescu@google.com, armellel@google.com, arve@android.com, ayrton@google.com, qperret@google.com, sebastianene@google.com, qwandor@google.com Subject: Re: [PATCH v8 5/7] KVM: arm64: Mask response to FFA_FEATURE call Message-ID: References: <20250719-virtio-msg-ffa-v8-0-03e8e8dbe856@google.com> <20250719-virtio-msg-ffa-v8-5-03e8e8dbe856@google.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20250719-virtio-msg-ffa-v8-5-03e8e8dbe856@google.com> On Sat, Jul 19, 2025 at 02:11:27AM +0000, Per Larsen via B4 Relay wrote: > From: Per Larsen > > The minimum size and alignment boundary for FFA_RXTX_MAP is returned in > bit[1:0]. Mask off any other bits in w2 when reading the minimum buffer > size in hyp_ffa_post_init. > > Signed-off-by: Per Larsen > --- > arch/arm64/kvm/hyp/nvhe/ffa.c | 2 +- > include/linux/arm_ffa.h | 1 + > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c > index 5a173ea481940236356e2bc4248d094a858a0923..2cbecc9af5d27a9e7c8497001cf9b0987c72bdb4 100644 > --- a/arch/arm64/kvm/hyp/nvhe/ffa.c > +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c > @@ -733,7 +733,7 @@ static int hyp_ffa_post_init(void) > if (res.a0 != FFA_SUCCESS) > return -EOPNOTSUPP; > > - switch (res.a2) { > + switch (res.a2 & FFA_FEAT_RXTX_MIN_SZ_MASK) { > case FFA_FEAT_RXTX_MIN_SZ_4K: > min_rxtx_sz = SZ_4K; > break; > diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h > index e1634897e159cdc208931938649eb0fb04d5a070..cd7ee4df9045dceca1c4e0dca2d533b770b1b056 100644 > --- a/include/linux/arm_ffa.h > +++ b/include/linux/arm_ffa.h > @@ -128,6 +128,7 @@ > #define FFA_FEAT_RXTX_MIN_SZ_4K 0 > #define FFA_FEAT_RXTX_MIN_SZ_64K 1 > #define FFA_FEAT_RXTX_MIN_SZ_16K 2 > +#define FFA_FEAT_RXTX_MIN_SZ_MASK GENMASK(1, 0) Acked-by: Will Deacon Will