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{ "id": 2195945, "url": "http://patchwork.ozlabs.org/api/covers/2195945/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260212-vfio_pci_ism-v1-0-333262ade074@linux.ibm.com/", "project": { "id": 28, "url": "http://patchwork.ozlabs.org/api/projects/28/?format=api", "name": "Linux PCI development", "link_name": "linux-pci", "list_id": "linux-pci.vger.kernel.org", "list_email": "linux-pci@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null, "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260212-vfio_pci_ism-v1-0-333262ade074@linux.ibm.com>", "list_archive_url": null, "date": "2026-02-12T14:02:14", "name": "[0/3] vfio/pci: Introduce vfio_pci driver for ISM devices", "submitter": { "id": 91782, "url": "http://patchwork.ozlabs.org/api/people/91782/?format=api", "name": "Julian Ruess", "email": "julianr@linux.ibm.com" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260212-vfio_pci_ism-v1-0-333262ade074@linux.ibm.com/mbox/", "series": [ { "id": 491980, "url": "http://patchwork.ozlabs.org/api/series/491980/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=491980", "date": "2026-02-12T14:02:17", "name": "vfio/pci: Introduce vfio_pci driver for ISM devices", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/491980/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2195945/comments/", "headers": { "Return-Path": "\n <linux-pci+bounces-47207-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-pci@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256\n header.s=pp1 header.b=CCUQ5n2l;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c0a:e001:db::12fc:5321; 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d=ibm.com; h=cc\n\t:content-transfer-encoding:content-type:date:from:message-id\n\t:mime-version:subject:to; s=pp1; bh=z9KnT6kiiqTL9pUGcsbZCQDdcvpr\n\ttBVFKD35eynel1Y=; b=CCUQ5n2lSuPid4QHdwiNNQX7Nx5SblJhqPJxnqjUefTN\n\tlewfuQEhY1pxpGnvqzUBXhFGZfehZ4xWzV+xjt1Boq6BMSM9QU76tQkdU9/dANQ7\n\thSqe/FHTcNcOYt9hy5onwUYGgHKrPuPPdNaFBMzJTQNvXKkRlZUSFaHs6xySaRCl\n\tQXx6bMdKFmsBtJCibtU7r7SmvM2Ns4BlhZrdPe5+Rdjn2t93dy43JkaxzBt6vWNb\n\t1rqe2Evaq5TeOlmH7XULF40ID5uPkKDzQNDTaCw1yZzJKJtJc3S9QpD/r9iIKnkd\n\t0tJeLeyLddCFHfUS/zB+MjaPKrRThI5VvP1vzpXXVQ==", "From": "Julian Ruess <julianr@linux.ibm.com>", "Subject": "[PATCH 0/3] vfio/pci: Introduce vfio_pci driver for ISM devices", "Date": "Thu, 12 Feb 2026 15:02:14 +0100", "Message-Id": "<20260212-vfio_pci_ism-v1-0-333262ade074@linux.ibm.com>", "Precedence": "bulk", "X-Mailing-List": "linux-pci@vger.kernel.org", "List-Id": "<linux-pci.vger.kernel.org>", "List-Subscribe": "<mailto:linux-pci+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-pci+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "Content-Type": "text/plain; charset=\"utf-8\"", "Content-Transfer-Encoding": "8bit", "X-B4-Tracking": "v=1; b=H4sIAGbdjWkC/33QTWrDMBAF4KsEreugGUkjKaveo5Sg30ZQ28FuT\n Urw3StnU9c1Xb4H8/GYOxvTUNLIToc7G9JUxtJ3NcDTgYWL695SU2LNDDkqjqibKZf+fA3lXMa\n 24SEETFIjSs3qyXVIudwe3MtrzZcyfvTD10OfcGkXiDiA+g1N2PAmkBOZFKkI4vm9dJ+3Y/HtM\n fQtW7BJrAG7AUQFIESA6BLXPO4BcgWg2AByWeBNFtqhRW/2ALUGtgtUBXQmq52QXjrYA+gHQE4\n bgCoQo9VCcktJ2z1A/wfoCkjyRsbsyELaA8wKANgApgJKSe6C9Wj+PnGe529gKQI7MgIAAA==", "X-Change-ID": "20250227-vfio_pci_ism-0ccc2e472247", "To": "schnelle@linux.ibm.com, wintera@linux.ibm.com, ts@linux.ibm.com,\n oberpar@linux.ibm.com, gbayer@linux.ibm.com,\n Alex Williamson <alex@shazbot.org>, Jason Gunthorpe <jgg@ziepe.ca>,\n Yishai Hadas <yishaih@nvidia.com>,\n Shameer Kolothum <skolothumtho@nvidia.com>,\n Kevin Tian <kevin.tian@intel.com>", "Cc": "mjrosato@linux.ibm.com, alifm@linux.ibm.com, raspl@linux.ibm.com,\n hca@linux.ibm.com, agordeev@linux.ibm.com, gor@linux.ibm.com,\n julianr@linux.ibm.com, kvm@vger.kernel.org,\n linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org,\n linux-pci@vger.kernel.org", "X-Mailer": "b4 0.14.2", "X-TM-AS-GCONF": "00", "X-Authority-Analysis": "v=2.4 cv=KZnfcAYD c=1 sm=1 tr=0 ts=698ddd7c cx=c_pps\n a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17\n a=IkcTkHD0fZMA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22\n a=Mpw57Om8IfrbqaoTuvik:22 a=GgsMoib0sEa3-_RKJdDe:22 a=VnNF1IyMAAAA:8\n a=buv0j8F9Xdj7ltUxVnMA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10", "X-Proofpoint-Spam-Details-Enc": "AW1haW4tMjYwMjEyMDEwNCBTYWx0ZWRfXzPCKsCWULGJ3\n EKlB9jnIEOFwXVSQFRRSR0ycYcB8HBsXIxba515f6hzOsJ3H27dZpVyCp3FT36NcdKe3Wy1NNH/\n hL96aqAVEKtSfoAxFg+Lt+YeWJqYNIY7PBNMI1KP7TGT943oPtPlYXljgwTpCPimVnXTxUcydN5\n FbAeGwDU44+RzQmxt4/TwD0uLfXLVQDn9D67o6cAGJoZFJCxUFpi1qIaUxqpKIiewKdvvVoZWfG\n uv+5FTt8ewY3Qq7ONQ1bNYR62Ov1/3WHFnLRmub5Vcam7EuDDLnUjcOwD+eXcUZKCEGGskOpKyt\n LAlbgBUleN2cOsxiFR//ibcjQxd8DUymXpGP7I/VkhaeJBbC3r+K1JSnGHpxkPLuHHigZbCeEfC\n N22fxoLRthluRsoADETKXODSG015Rp89q10ZWDDVUDymsR8RaveakpgmRTwdv7ua1kw6+0qpAuN\n xjzSDeJE0+KVHB8w4gA==", "X-Proofpoint-ORIG-GUID": "E6uP3_QtvQIhaO-aBG1j4w1DthdtX17k", "X-Proofpoint-GUID": "E6uP3_QtvQIhaO-aBG1j4w1DthdtX17k", "X-Proofpoint-Virus-Version": "vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-02-12_04,2026-02-12_02,2025-10-01_01", "X-Proofpoint-Spam-Details": "rule=outbound_notspam policy=outbound score=0\n spamscore=0 impostorscore=0 bulkscore=0 priorityscore=1501 adultscore=0\n clxscore=1015 suspectscore=0 phishscore=0 malwarescore=0 lowpriorityscore=0\n classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0\n reason=mlx scancount=1 engine=8.22.0-2601150000 definitions=main-2602120104" }, "content": "Hi all,\n\nThis series adds a vfio_pci variant driver for the s390-specific\nInternal Shared Memory (ISM) devices used for inter-VM communication\nincluding SMC-D.\n\nThis is a prerequisite for an in-development open-source user space\ndriver stack that will allow to use ISM devices to provide remote\nconsole and block device functionality. This stack will be part of\ns390-tools.\n\nThis driver would also allow QEMU to mediate access to an ISM device,\nenabling a form of PCI pass‑through even for guests whose hardware\ncannot directly execute PCI accesses, such as nested guests.\n\nOn s390, kernel primitives such as ioread() and iowrite() are switched\nover from function handle based PCI load/stores instructions to PCI\nmemory-I/O (MIO) loads/stores when these are available and not\nexplicitly disabled. Since these instructions cannot be used with ISM\ndevices, ensure that classic function handle-based PCI instructions are\nused instead.\n\nThe driver is still required even when MIO instructions are disabled, as\nthe ISM device relies on the PCI store‑block (PCISTB) instruction to\nperform write operations.\n\nThank you,\nJulian\n\nSigned-off-by: Julian Ruess <julianr@linux.ibm.com>\n---\nJulian Ruess (3):\n vfio/pci: Set VFIO_PCI_OFFSET_SHIFT to 48\n vfio/ism: Implement vfio_pci driver for ISM devices\n MAINTAINERS: add VFIO ISM PCI DRIVER section\n\n MAINTAINERS | 6 +\n drivers/vfio/pci/Kconfig | 2 +\n drivers/vfio/pci/Makefile | 2 +\n drivers/vfio/pci/ism/Kconfig | 11 ++\n drivers/vfio/pci/ism/Makefile | 3 +\n drivers/vfio/pci/ism/main.c | 227 +++++++++++++++++++++++++++++++++++++\n drivers/vfio/pci/vfio_pci_config.c | 1 +\n drivers/vfio/pci/vfio_pci_core.c | 4 +-\n include/linux/vfio_pci_core.h | 2 +-\n 9 files changed, 255 insertions(+), 3 deletions(-)\n---\nbase-commit: 05f7e89ab9731565d8a62e3b5d1ec206485eeb0b\nchange-id: 20250227-vfio_pci_ism-0ccc2e472247\n\nBest regards," }