From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 53E103FBB6D for ; Wed, 10 Jun 2026 15:19:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781104746; cv=none; b=k9Z959zFpDRPyG5oTSIs72i4Ir7cEhZ6t7XXIjximophhRefAAQPa3QNLJcxPgP/YQZaW3m6YcfQWV7CqqKJ6e5UecVJ+A2HJuIFJZKmvccEKZ12bLfhxYfo89KzqnH/0HtAS076h89HREDWmWmSFTSAWERh9BlUH/xZ2tDH/3c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781104746; c=relaxed/simple; bh=W26xzmE+jrRyJeg4sgHUoiNG1TPKjNOWHbVy/H0Zo3Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bv4SrYkuLSfmZ9bNRs5wSn4EHwKT05ikFVOLUI4vCdCI4RpNdddm73svy+OdxQSqfbsqrFajmMIn/mxSayXNkwtJWJj5ota5sW23kN7kuQDEU3VczLz4cwIbwIig48KUvw5XcknlcOHNUN3vWcG+ZV2XEdJCgYAGMO3O/RvrA6E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--praan.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=gDqR0h5T; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--praan.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="gDqR0h5T" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2bfdd99f6b7so98295915ad.0 for ; Wed, 10 Jun 2026 08:19:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781104743; x=1781709543; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=eqTJwQH8YsAF6LO/DgujemeBJs4CWAElVi/rnkffuXw=; b=gDqR0h5TorA42u8xiUG/9P0ak940+YeUImN5hBFzeqf3InpBnnrExXV80RjAdGBpcE 3xJY8YxuATi4cNYhM+FC3DwuCgq46XfL3rzxwudUyHztNzIf8cilc//K9sxpaJj0qbHM PALRkLdoGiwtPAT/g5xVXTOUARkADrfDOHuCsYlVCANKa/k9tdZpYy63uBX17LMPW4E5 vJ2SZI+5wVgoZiKTvOb2HF3IoK2HBenB8mdxtQSzb1n5O9c8ohvno6rU6bq8qcpf+cJg dNLgJuUqUko68emGDnZXEHUD0o76tJt283ttwvdwD27vv2chdJRhaTBJKbSVTgMXys01 Oowg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781104743; x=1781709543; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=eqTJwQH8YsAF6LO/DgujemeBJs4CWAElVi/rnkffuXw=; b=T42LcaP+sX8TLECg6VFt1Oaonv6zdGpje+P6o47KW/raAJcVd0VBvgyUUhCprGhRDR gk87ersCjBuPI1WYnG6rP6nSxO4SiG2JBAucUXj7UrWAOyl+UEQJhCA07F6ILSYO4ek1 h8/4B0kYqXRleUoW3ksmUmhPkNsRvLhiu0f0MJou/nUGNONx+2yD8CTLjWJeer9fkG9B KhylkiYbvelgdXSP4xYEdOlYL/zet3Bus5xjdeuGDQYRdkxsaI4YboVe0oG0m+FZxpZ9 HGV4RI0iZowOjRuxsavHEMbibQPFeb+5tnetX5injsOuz03AFILkUX6pPShQSNT/Uncd VBcw== X-Forwarded-Encrypted: i=1; AFNElJ9+Pc6qErxXzNGWwJvR+0xnw1Eru7g9x+C20dHBRVIL7jMR4CzDyFWQ5QFyn+fqBfwRB3G3yELcAroRIHo=@vger.kernel.org X-Gm-Message-State: AOJu0YxOuX8D3Qqr21mfdigRY+kTY5UEKGvSB84TmeZohL30Nau390iQ DSuoK51QcBrrxQdBKLLU+OBUdrlHjei0fOBPpWTAdccO27nIEXKX967+P64SN+E+NgLo8w7m572 fBQ== X-Received: from plby21.prod.google.com ([2002:a17:902:ed55:b0:2c1:9d1:eeb0]) (user=praan job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:291:b0:2c0:c940:dc32 with SMTP id d9443c01a7336-2c1e821dde8mr301857195ad.16.1781104742341; Wed, 10 Jun 2026 08:19:02 -0700 (PDT) Date: Wed, 10 Jun 2026 15:18:51 +0000 In-Reply-To: <20260610151853.3608948-1-praan@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260610151853.3608948-1-praan@google.com> X-Mailer: git-send-email 2.54.0.1099.g489fc7bff1-goog Message-ID: <20260610151853.3608948-4-praan@google.com> Subject: [RFC PATCH 3/5] vfio/pci: Block mmap & dmabuf export for ZONE_DEVICE-registered BARs From: Pranjal Shrivastava To: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Bjorn Helgaas , Logan Gunthorpe , Alex Williamson , Jason Gunthorpe , Kevin Tian , Pranjal Shrivastava , Ankit Agrawal , Matt Evans , Vivek Kasireddy , Leon Romanovsky , Shivaji Kant , Samiullah Khawaja Content-Type: text/plain; charset="UTF-8" Update vfio_pci_core_mmap() & vfio_pci_core_feature_dma_buf() to enforce mutual exclusivity with ZONE_DEVICE P2P registration. If a BAR has been registered for native P2P (via VFIO_DEVICE_FEATURE_P2P_REGISTER), subsequent requests to mmap the BAR or export it as a DMABUF are rejected with -EBUSY. Signed-off-by: Pranjal Shrivastava --- drivers/vfio/pci/vfio_pci_core.c | 7 +++++++ drivers/vfio/pci/vfio_pci_dmabuf.c | 6 ++++++ 2 files changed, 13 insertions(+) diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index 1e922e3aaeb3..9cf494b765e7 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -1828,6 +1828,13 @@ int vfio_pci_core_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma if (!vdev->bar_mmap_supported[index]) return -EINVAL; + if (vdev->p2p_registered_bars & (1 << index)) { + pci_warn(vdev->pdev, + "BAR %d registered for P2P. Use sysfs to allocate\n", + index); + return -EBUSY; + } + phys_len = PAGE_ALIGN(pci_resource_len(pdev, index)); req_len = vma->vm_end - vma->vm_start; pgoff = vma->vm_pgoff & diff --git a/drivers/vfio/pci/vfio_pci_dmabuf.c b/drivers/vfio/pci/vfio_pci_dmabuf.c index c16f460c01d6..6635a8681291 100644 --- a/drivers/vfio/pci/vfio_pci_dmabuf.c +++ b/drivers/vfio/pci/vfio_pci_dmabuf.c @@ -251,6 +251,12 @@ int vfio_pci_core_feature_dma_buf(struct vfio_pci_core_device *vdev, u32 flags, IS_ERR(vfio_pci_core_get_iomap(vdev, get_dma_buf.region_index))) return -ENODEV; + if (vdev->p2p_registered_bars & (1 << get_dma_buf.region_index)) { + pci_warn(vdev->pdev, "BAR %d registered for native P2P. Use sysfs for allocation.\n", + get_dma_buf.region_index); + return -EBUSY; + } + dma_ranges = memdup_array_user(&arg->dma_ranges, get_dma_buf.nr_ranges, sizeof(*dma_ranges)); if (IS_ERR(dma_ranges)) -- 2.54.0.1099.g489fc7bff1-goog