A kernel regression appeared in v4.20-rc4 regarding a specific form of DMA for PCI (PCIe?) devices. It has been, or will be, patched in v5.31 upstream I believe; I presented the bisect to iommu@linuxfoundation,org, and after their great assistance used the resulting patch against v5.2 successfully and corrected the issues with my Fedora system. I am not sure of plans to bring it back to v5.x, but ask that you do, especially during this Fedora v5.2 test week. I have included the header so you can retrieve it from the canonical source. I have more info if needed. Thank You. Reviewed-by: Robin Murphy <robin.murphy> > Fixes: 55897af63091("dma-direct: merge swiotlb_dma_ops into the dma_direct code") > Signed-off-by: Fugang Duan <fugang.duan> > --- > kernel/dma/direct.c | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) > > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index b90e1ae..0e87f86 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -242,12 +242,14 @@ void dma_direct_sync_sg_for_device(struct device *dev, > int i; > for_each_sg(sgl, sg, nents, i) { > - if (unlikely(is_swiotlb_buffer(sg_phys(sg)))) <further content deleted>
The header isn't helpful here since I don't actually know where to track down the canonical source from just that snippet. It has the fixes tag so it would get picked up automatically eventually. Please provide a pointer to the full patch so we can make sure that gets included sooner.
Sorry; I left out some info - here is how to find it... I went to iommu, select this month, typed in Fugang (the author at NXP). https://lists.linuxfoundation.org/pipermail/iommu/2019-July/037428.html Here is the commit as of two days ago, combined w/other fixes... https://github.com/torvalds/linux/commit/ac60602a6d8f6830dee89f4b87ee005f62eb7171 commit ac60602a6d8f6830dee89f4b87ee005f62eb7171
FEDORA-2019-3dbfaeac73 has been submitted as an update to Fedora 29. https://bodhi.fedoraproject.org/updates/FEDORA-2019-3dbfaeac73
kernel-5.1.20-200.fc29, kernel-headers-5.1.20-200.fc29 has been pushed to the Fedora 29 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-3dbfaeac73
kernel-5.1.20-300.fc30, kernel-headers-5.1.20-300.fc30 has been pushed to the Fedora 30 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-167e7fc29a
kernel-5.1.20-300.fc30, kernel-headers-5.1.20-300.fc30 has been pushed to the Fedora 30 stable repository. If problems still persist, please make note of it in this bug report.
kernel-5.1.20-200.fc29, kernel-headers-5.1.20-200.fc29 has been pushed to the Fedora 29 stable repository. If problems still persist, please make note of it in this bug report.