From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f174.google.com (mail-qk1-f174.google.com [209.85.222.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8418079C0 for ; Wed, 30 Aug 2023 20:36:24 +0000 (UTC) Received: by mail-qk1-f174.google.com with SMTP id af79cd13be357-76ef8b91a4bso5813585a.2 for ; Wed, 30 Aug 2023 13:36:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1693427783; x=1694032583; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=Z9olKQHKl7i+BW/Fox3jX2swhAkTGXKGKjmjdi6zQOQ=; b=HTUcoTLVMJKPopZPx5brkas77UDvQYIjC7naYepzkdyyLzaJgfCC4cC5JwAlVN0zw1 5odTw/6Hh+io9S7cO6rfMvYLDEIO31IiUr2Ztxc0c4RXaRW/AQxyvJt7L8RhEjF+70Q5 CpGWsPg7PSJD4GIAbJjZLxoJza2f1yWwsk2G5rXvuB0C6AuXl1N4ZTOo0aE/BzZe1ry/ DeU82ThH2Wp8XHdQvgsrZKiwnykZkwQ6JyF/yK2A3WmiYJekHvF6whUxF6TON22sjDS0 aYFBHQUZvzQ/x5K83sbvTba63wgYXeHxAC8YZ2ftW2bpIroxOrkiRrsDr016wMs08bUZ TOHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693427783; x=1694032583; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=Z9olKQHKl7i+BW/Fox3jX2swhAkTGXKGKjmjdi6zQOQ=; b=N3t8KpPeCdpl3ovEziJExMS2TzfDmuLgcHzaFAV3ThfvU2TXE02ul7SwXdkR5YGCqS s8fccVVBxjo+k3OTRDsYH+qhBa6+plgk+JfOoYzEzRMVAkYGoUcwBESohasLRs2DE7gF qMzC0iQ4s4WnifNsTMBPanKFWwDMIw44LnRhaQ/Rr50HIWqkpI3iw9T9/o2g6P9ilDD3 Cao/QCnG3BUc+S3ami6yNJzVcwmvMICTvusRupocjH53YkQO8sD45KKTFBEw/Gg4is1+ 8jC+oLEDGCG7R6ptRBh2/NxkRE3GpKPJDJR+5orKk0/ivWuT9v8S2dVKsJs60CC9t5Jo AMsg== X-Gm-Message-State: AOJu0YzNKgXs173U8UkDF4HQwAjyiz1F5gxk9NBWOM60Rf+pNUUNXdAF XoebsEKuuzyIowr11w5DVQFgwA== X-Google-Smtp-Source: AGHT+IGF4MU0rD+iQwT0aCopRevdjBpeHCOTE0yYV5wWvsuXnz48NfHVfNaBhCyzBhEFTczQi1j9zA== X-Received: by 2002:a05:620a:3727:b0:768:1572:e9af with SMTP id de39-20020a05620a372700b007681572e9afmr1073374qkb.8.1693427783197; Wed, 30 Aug 2023 13:36:23 -0700 (PDT) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id pj37-20020a05620a1da500b0076da620166bsm3998312qkn.103.2023.08.30.13.36.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Aug 2023 13:36:22 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1qbRvI-000DB0-Qb; Wed, 30 Aug 2023 17:36:20 -0300 Date: Wed, 30 Aug 2023 17:36:20 -0300 From: Jason Gunthorpe To: Vasant Hegde Cc: Tina Zhang , Kevin Tian , Lu Baolu , Michael Shavit , iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 4/5] iommu: Support mm PASID 1:n with sva domains Message-ID: References: <20230827084401.819852-1-tina.zhang@intel.com> <20230827084401.819852-5-tina.zhang@intel.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Aug 28, 2023 at 02:02:52PM +0530, Vasant Hegde wrote: > I am not sure whether I understood the flow completely. Just wondering why you > are not freeing pasid in iommu_sva_unbind_device(). > I mean once iommu_mm->sva_domains becomes free shouldn't we free the > iommu_mm->pasid? No, for Intel use cases that PASID permanently becomes part of the ENQCMD MSR and cannot be revoked once it has been set > Also in this function (mm_pasid_drop()), should we check/free sva domains? No, the driver must support a SVA domain with an empty mm_struct, eg by hooking release. Jason