From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f195.google.com (mail-qk1-f195.google.com [209.85.222.195]) (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 D97292DC79B for ; Mon, 19 Jan 2026 19:54:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768852489; cv=none; b=PVhRLT0Aq9MhlAvT4AIUtyYHHivrTZyv4G/yMbiDuC74JXPf0Qrm6akMIxq5y1zjg+ZaYWEC0nbDInzMi54M89ZhNRxuQVGM//NXbESFAYR4DfDh+yxItfbO7yatB+g+Mh6iB2zNHmWnMsHbieeh6xNOdldlHLGADULHZYCEsSA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768852489; c=relaxed/simple; bh=EgdbrvHnoBh/zDpp9ewcIGQxrvWxBBXiNgVYU0RjdCs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pv+xdsIxg9TrZCTR6SXjKmjFaCva0l3MvNXPoRtjHBVYzfwi6yuXOJF8WyIPylccsXV154IXvqUGVdMKkgpN7KQtDkDqczjzsTbXYFrK7FwP6z7eYPN5QWXs8wFnbBJM2vfiSJcY6b6RVydO+tDwebRHSMqAB7EuGTwRksU/PcM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca; spf=pass smtp.mailfrom=ziepe.ca; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b=Jql7siU7; arc=none smtp.client-ip=209.85.222.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="Jql7siU7" Received: by mail-qk1-f195.google.com with SMTP id af79cd13be357-8c52c1d2a7bso624125385a.0 for ; Mon, 19 Jan 2026 11:54:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1768852487; x=1769457287; darn=lists.linux.dev; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=zwZ9o3ha19w1BUlcGeJzNZvsy/mlKSz+FRMjn04+Z/c=; b=Jql7siU7T8SrrFxwgL7D9N+WTkMzGGs+iG6gvPay9LI2pvvaVfqW06kcfcSkbbR3jD bO4XMm/OaAiLfdx8fhwxKmjL/W0UOkLIGm/Cmw+P5/WbB3hm9O5yY7Ibq7Y59uOIJD53 aD9Wz/Wjye6+HL13ZBT4FTDzf3RIkLZq7gbPBenA1Uqlw/6978nu2sbVUemD7iw3QTXD SWoGV+tmqh8Ps5OZ5Xdoq/h5l6pOlpeAAgwStPrQs7AUoA7Hv9wFWw0w25LdcRALjOSM EElVIdIZzJ9S3FQfxF+RBNbNmtCM0nh6UOZytVabwsXnRI1ESVghlUy0WkeoUWtgt4qT SsHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768852487; x=1769457287; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=zwZ9o3ha19w1BUlcGeJzNZvsy/mlKSz+FRMjn04+Z/c=; b=qC/EqPQvr5Zi54MFWSHgS0RKNR55QT504UcPHApl0C4wTdwZ4sEIDmVMtbLVTqHNWs 6V6Zzg9Izsaa5pGEJ0iQG+QRI+fev604fk4ejcqiV8km9VG4GOBZujWU7AfPkixgq3ZO 1fZBgH0shyQfE6C9GQ9b/iPio2gxMoWPiZP+DCysCBnRSl+KlDVVzW7SW9GDDf0iLvfS hwjOPm6+5KMKgCGg3wR5DFFFPWEW5CuxTTyhkJPKLnd/HN7mqz9PQsY7xLgGioPq45EX us7gQNoe84yIWiQ16Lk/YSQUPlMOSV9NfcbE4LQxlUXmtorOCjlst/t++k/WVfOlrINB Ks3Q== X-Forwarded-Encrypted: i=1; AJvYcCWu7urwNvH+CiDNfGMjU0qwvrICq1VvFTSbBEAIwiHjmgUPCwsQNckp9j57IXHl+NiyCNeiog==@lists.linux.dev X-Gm-Message-State: AOJu0Yyxx+cVmCLgGC3S2WCeU0jd3bW+qI1EwGV0/hg6XNdOsaYTnYE4 O7hpKrTslHDe97Xa0Am6f7+Yb61NdB7VUBbwe0NgmKUnNX67X0Gz4+4bnH1RTbSPAsw= X-Gm-Gg: AY/fxX4FmVx44A0UDZ62wwCPcvc9hn5n8Pt9hAW+oS/7TK/4BV6UDu/w+G+NgmEEyA8 b6UkdwlmdTj5WZkgSfrOkKPZaBw2Z5cOdi4lJidQg50w2Y0N5tJabT38JbGtejPLMVWY1lHXx0i aaGC+3tEnsry1+GJeVrzRLuMvotVxb3RuNpb4BgNxlmUa1vmSb0IrDkxC2f07rTGsIGfnKlqTay 1FrrwLmtgEFXjOqWWxG8JJHY2H4rSZgSAwCwBnn/IKint/l85mWoeLM+adIU68CT0QOZCERrBbK DaRA+tvpfB7li3suPwhE4Jbf3XiQZT3cT3NtyfiF76zOZYGCXKa9eFWKVAHjLb3BciMnx7uWLnN igFCYQvcZh2BumyAiwvMDeNMpi3hmAk78UGCJFTGyk4pWfAKmsErBvp9FN2uUER4v0tWwdLtjmY UsCNZksIsthFU1v0gqFxpA6bgICOOBeMQrbw8JG1PHjeIWEn4fmFflhMPkEMeihxaBp6U= X-Received: by 2002:a05:620a:4606:b0:8a3:a42e:6e14 with SMTP id af79cd13be357-8c589b9706emr2117693085a.10.1768852486747; Mon, 19 Jan 2026 11:54:46 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-142-162-112-119.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.112.119]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8942e6ad75asm86947906d6.31.2026.01.19.11.54.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Jan 2026 11:54:44 -0800 (PST) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1vhvKm-00000005JRT-0mKA; Mon, 19 Jan 2026 15:54:44 -0400 Date: Mon, 19 Jan 2026 15:54:44 -0400 From: Jason Gunthorpe To: Leon Romanovsky Cc: Sumit Semwal , Christian =?utf-8?B?S8O2bmln?= , Alex Deucher , David Airlie , Simona Vetter , Gerd Hoffmann , Dmitry Osipenko , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Lucas De Marchi , Thomas =?utf-8?Q?Hellstr=C3=B6m?= , Rodrigo Vivi , Kevin Tian , Joerg Roedel , Will Deacon , Robin Murphy , Alex Williamson , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, virtualization@lists.linux.dev, intel-xe@lists.freedesktop.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, kvm@vger.kernel.org Subject: Re: [PATCH v2 3/4] iommufd: Require DMABUF revoke semantics Message-ID: <20260119195444.GL961572@ziepe.ca> References: <20260118-dmabuf-revoke-v2-0-a03bb27c0875@nvidia.com> <20260118-dmabuf-revoke-v2-3-a03bb27c0875@nvidia.com> <20260119165951.GI961572@ziepe.ca> <20260119182300.GO13201@unreal> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260119182300.GO13201@unreal> On Mon, Jan 19, 2026 at 08:23:00PM +0200, Leon Romanovsky wrote: > On Mon, Jan 19, 2026 at 12:59:51PM -0400, Jason Gunthorpe wrote: > > On Sun, Jan 18, 2026 at 02:08:47PM +0200, Leon Romanovsky wrote: > > > From: Leon Romanovsky > > > > > > IOMMUFD does not support page fault handling, and after a call to > > > .invalidate_mappings() all mappings become invalid. Ensure that > > > the IOMMUFD DMABUF importer is bound to a revoke‑aware DMABUF exporter > > > (for example, VFIO). > > > > > > Signed-off-by: Leon Romanovsky > > > --- > > > drivers/iommu/iommufd/pages.c | 9 ++++++++- > > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/iommu/iommufd/pages.c b/drivers/iommu/iommufd/pages.c > > > index 76f900fa1687..a5eb2bc4ef48 100644 > > > --- a/drivers/iommu/iommufd/pages.c > > > +++ b/drivers/iommu/iommufd/pages.c > > > @@ -1501,16 +1501,22 @@ static int iopt_map_dmabuf(struct iommufd_ctx *ictx, struct iopt_pages *pages, > > > mutex_unlock(&pages->mutex); > > > } > > > > > > - rc = sym_vfio_pci_dma_buf_iommufd_map(attach, &pages->dmabuf.phys); > > > + rc = dma_buf_pin(attach); > > > if (rc) > > > goto err_detach; > > > > > > + rc = sym_vfio_pci_dma_buf_iommufd_map(attach, &pages->dmabuf.phys); > > > + if (rc) > > > + goto err_unpin; > > > + > > > dma_resv_unlock(dmabuf->resv); > > > > > > /* On success iopt_release_pages() will detach and put the dmabuf. */ > > > pages->dmabuf.attach = attach; > > > return 0; > > > > Don't we need an explicit unpin after unmapping? > > Yes, but this patch is going to be dropped in v3 because of this > suggestion. > https://lore.kernel.org/all/a397ff1e-615f-4873-98a9-940f9c16f85c@amd.com That's not right, that suggestion is about changing VFIO. iommufd must still act as a pinning importer! Jason