On Tue, 12 Jul 2016 20:29:13 -0500 David <david...@gmail.com> wrote: > the command "dmesg | grep -i dma" Give no results. Is there anything > else i should check Alex? > > If the solution to this is to submit a bug report, who should i send > it too? I believe the AACRAID driver is built into the Linux kernel.
How about sending the full, uncut, unfiltered dmesg out first? Have you tried adding iommu=pt as a boot option? Thanks, Alex > On Tue, Jul 12, 2016 at 9:51 AM, Alex Williamson > <alex.william...@redhat.com> wrote: > > On Sun, 10 Jul 2016 13:17:41 -0500 > > David <david...@gmail.com> wrote: > > > >> I have run into a strange problem, while setting up my Fedora 24 box for > >> KVM, i noticed that my raid array stopped showing as an available drive. > >> After a lot of troubleshooting and reinstalling linux to this PC 2 more > >> times, i have narrowed it down to one setting in my GRUB config. > >> intel_iommu=on > >> > >> Just taking that one setting out and rebuilding my grub2-efi.cfg will make > >> the array readable again. When IOMMU is on, the system can see that there > >> is a raid card and array, but it lists the partition table as unknown. It > >> also will not successfully create a new GPT partition table on the array. > >> With IOMMU off, it can read the partition table and partition fine, read > >> and write data, and everything works fine. > >> > >> My raid is 4 1TB disks in Raid 10e, GPT partition formatted NTFS. > >> > >> $ lspci -v -s 03:0e.0 > >> 03:0e.0 RAID bus controller: Adaptec AAC-RAID > >> Subsystem: Adaptec 3805 > >> Flags: bus master, stepping, 66MHz, medium devsel, latency 32, IRQ 57 > >> Memory at fa600000 (64-bit, non-prefetchable) [size=2M] > >> Expansion ROM at fa800000 [disabled] [size=256K] > >> Capabilities: <access denied> > >> Kernel driver in use: aacraid > >> Kernel modules: aacraid > > > > > > No DMAR faults in dmesg? There's a fair chance this is one of those > > devices that does DMA with the wrong requester ID and therefore > > enabling the IOMMU prevents it from working. We have a mechanism in > > the kernel to handle such DMA aliasing if you can verify the issue. > > Thanks, > > > > Alex > > > _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
