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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F302BEE0219 for ; Wed, 11 Sep 2024 08:26:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:Cc:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=s5+iwZVnde4LK1kAdLszfIVUOBu8rR4Q+jBuk1OQXjQ=; b=QxO3d3N7mtj5udc8JY4DX4QjZd Z2/3quGZmdXKC0Ccwzi3tAj+fjGYsIxec5TRBGwGnrI0caT8MvWwS/qwXBFFCX7Ig1Q7txcRVAO95 kRG1MUIFfjIE3iwg/83aXhtl4PQJJpkwuQEPL4pjI7oHi5bHBa7BILP0jcML6J2l7eIiOwX5emFxW Z94HjPYCkQMkYCBhY0eBREE7v8PEM0SJlKrl1IpUZQJaKJJd6sNXbtyAH3K6KD6osdDgD6hyhyLck 5jRUYq9UiN1lA6+ubNz7BXpoAw0N8MmjJSIfHIpc7xdK8vNIxxbxO5t/SYLawg5mfI/P469aIoKOr VdRa9FHg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1soIgU-00000008dwQ-1xoi; Wed, 11 Sep 2024 08:26:42 +0000 Received: from mgamail.intel.com ([192.198.163.14]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1soIZE-00000008bgl-1Hn7 for linux-arm-kernel@lists.infradead.org; Wed, 11 Sep 2024 08:19:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726042752; x=1757578752; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=C/M/OlJkOy173Oq31V96XkHyPvV/Jp4PU2/AH6EcOCg=; b=lBnpahuufyOhnE0I2nPcWzIuTJtsaeMmV57krKKYDpesF5LfYB/g3O/I YwfxKLZ5ROBnibRy0qUlBE7r+YTIAn1l3BrvUhBsx48X1KMHLacfHpRC7 khzQKLpvWG49vr/3K1JBkrqMdcr1H2MuG/knexpDk5ZzDqfabfGs0+1Pf kHTs0+mmgEEG/506KH75WTKPxaJ8rSkhK8vJMk/Q4/WKIGKr614PQkiDF EVtZEiyhbj5SZdDMve+ykrMn7+f94vNJ6+s48P1QWfIlNigjDS/yZu09v HkXw+RlXCXx2zuE2PL1tKQ0h/IMP0IyIs2LR1dP5SFjj/514zpsKRgHrN g==; X-CSE-ConnectionGUID: bMxkuCR3QgqH0XDvvdyXjA== X-CSE-MsgGUID: ZQY+RWW/R5SrSg79tOxMGg== X-IronPort-AV: E=McAfee;i="6700,10204,11191"; a="25023336" X-IronPort-AV: E=Sophos;i="6.10,219,1719903600"; d="scan'208";a="25023336" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa108.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Sep 2024 01:19:11 -0700 X-CSE-ConnectionGUID: aICFU60vTDaH4pMBepREEQ== X-CSE-MsgGUID: OEGGNQiHQVWbJL021rouaA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,219,1719903600"; d="scan'208";a="72275297" Received: from blu2-mobl.ccr.corp.intel.com (HELO [10.124.240.228]) ([10.124.240.228]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Sep 2024 01:19:07 -0700 Message-ID: <46158923-046b-44e3-a67f-0964c53dd0b5@linux.intel.com> Date: Wed, 11 Sep 2024 16:19:04 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: baolu.lu@linux.intel.com, Jason Gunthorpe , "will@kernel.org" , "joro@8bytes.org" , "suravee.suthikulpanit@amd.com" , "robin.murphy@arm.com" , "dwmw2@infradead.org" , "shuah@kernel.org" , "linux-kernel@vger.kernel.org" , "iommu@lists.linux.dev" , "linux-arm-kernel@lists.infradead.org" , "linux-kselftest@vger.kernel.org" , "eric.auger@redhat.com" , "jean-philippe@linaro.org" , "mdf@kernel.org" , "mshavit@google.com" , "shameerali.kolothum.thodi@huawei.com" , "smostafa@google.com" , "Liu, Yi L" Subject: Re: [PATCH v2 17/19] iommu/arm-smmu-v3: Add arm_smmu_viommu_cache_invalidate To: "Tian, Kevin" , Nicolin Chen References: <4b61aba3bc6c1cce628d9db44d5b18ea567a8be1.1724776335.git.nicolinc@nvidia.com> <20240905162039.GT1358970@nvidia.com> <20240905182148.GA1358970@nvidia.com> Content-Language: en-US From: Baolu Lu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240911_011912_389159_ACCD87D7 X-CRM114-Status: GOOD ( 10.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2024/9/11 16:17, Tian, Kevin wrote: >> If a VMID for an S2 hwpt is valid on physical IOMMU A but has already >> been allocated for another purpose on physical IOMMU B, how can it be >> shared across both IOMMUs? Or the VMID is allocated globally? >> > I'm not sure that's a problem. The point is that each vIOMMU object > will get a VMID from the SMMU which it's associated to (assume > one vIOMMU cannot span multiple SMMU). Whether that VMID > is globally allocated or per-SMMU is the policy in the SMMU driver. > > It's the driver's responsibility to ensure not using a conflicting VMID > when creating an vIOMMU instance. Make sense. Thanks, baolu