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charset="UTF-8" Content-Transfer-Encoding: quoted-printable Date: Thu, 23 Apr 2026 21:04:25 +0200 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-GUID: 4AgvFRtSjGI8rQmNSXteRbPifdrTHJvy X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDIzMDE4MyBTYWx0ZWRfX1X8fbM12GOpD 231eTKlsu9csx89VGXcVyZSOyOXky8tfWW0PiGJQsg66EmcNa2SCImyvzheV33ga61yusfKH/L7 yHcpLqgM+QXTRRpXGemIe/Jcjkl6sFbdBJ4HxMQ2B/BfuwkucBTMEEGjZSCyEij4GnADFaTFL5p ux+8bl5vro3aLwGnnxkVGqvBsmtBmvi4Ip+MLBAB2hydKYJf6H93l8QrlznDifk9wM3WwfWko37 vJrv1LjY51xxEda52zK6a+in6QOHJP1e1sCY/GT+DF1usgoluBEtYUa7UQrW7C6SKCmqNLY67wk EpJK6ekgjBHt6Ew4dpZdH2JzVssaSE82+GWxLWXTNltDzqA18wMWSRxot0Tq18d0C5YTRPM0o/M Oon7wovhqx3ub1+emyL6JhDunBu8LMfVldqbS/IKhEUZxubLLLJrQwDg2vFVkStMPhXCY3QFzza 4J1Uw8Uau1Q0pQ2TsoQ== X-Authority-Analysis: v=2.4 cv=a6kAM0SF c=1 sm=1 tr=0 ts=69ea6d79 cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=VwQbUJbxAAAA:8 a=VabnemYjAAAA:8 a=VnNF1IyMAAAA:8 a=teCjjoZnVze8JZkblVgA:9 a=QEXdDO2ut3YA:10 a=gKebqoRLp9LExxC7YDUY:22 X-Proofpoint-ORIG-GUID: LPm2vYsAhkVaGLjFsbCFuV1L7ANeR68m X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-23_03,2026-04-21_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 spamscore=0 adultscore=0 bulkscore=0 lowpriorityscore=0 impostorscore=0 clxscore=1015 phishscore=0 priorityscore=1501 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604200000 definitions=main-2604230183 On Thu, 2026-04-23 at 10:30 -0700, Matt Evans wrote: > Extend the checks in pcim_p2pdma_init() and pcim_p2pdma_provider() to > exclude functions that have pdev->non_mappable_bars set. >=20 > Consumers such as VFIO were previously able to map these for access by > the CPU or P2P. Update the comment on non_mappable_bars to show it > refers to any access, not just userspace CPU access. >=20 > Fixes: 372d6d1b8ae3c ("PCI/P2PDMA: Refactor to separate core P2P function= ality from memory allocation") > Signed-off-by: Matt Evans > --- >=20 > This arises from Alex Williamson's suggestion to test > non_mappable_bars when getting the provider, with discussion here: >=20 > https://lore.kernel.org/kvm/20260415181623.1021090-1-mattev@meta.com/ >=20 > The goal was to prevent a hole where VFIO could export DMABUFs for > BARs marked non-mappable, and to fix for all users of the provider > rather than just VFIO. Alex observed that non_mappable_bars should be > taken to mean BARs weren't usable by the CPU _or_ peers and, > considering that, its comment about userspace access wasn't quite > right. >=20 > =3D=3D Changes =3D=3D >=20 > v2: > - Also test non_mappable_bars in pcim_p2pdma_init(), as > otherwise pci_p2pdma_add_resource() will WARN_ON > pcim_p2pdma_provider() failing. >=20 > Niklas and Logan, I didn't re-add your R-B from v1 as (splitting > hairs...) the code's changed. >=20 Makes sense, now feel free to re-add ;) Reviewed-by: Niklas Schnelle =20 Thanks, Niklas