On Thu, Oct 6, 2016 at 8:30 PM, A223 A223 <andj2...@gmail.com> wrote: > On Thu, Oct 6, 2016 at 9:46 AM, Alex Williamson > <alex.william...@redhat.com> wrote: >> On Wed, 5 Oct 2016 20:30:34 -0700 >> A223 A223 <andj2...@gmail.com> wrote: >> >>> On Wed, Oct 5, 2016 at 9:33 AM, Alex Williamson >>> <alex.william...@redhat.com> wrote: >>> > On Wed, 5 Oct 2016 02:13:21 -0700 >>> > A223 A223 <andj2...@gmail.com> wrote: >>> >> How can I go about tracking down the root cause of this error? >>> > >>> > This often means that the device resources are in use by another, >>> > non-pci driver. Look in /proc/iomem and /proc/ioport to see if any >>> > drivers are claiming sub-regions on the device. You can also turn on >>> > tracing and look for the event vfio_region_mmap_fault, which might give >>> > us more information (see docs/tracing.txt). Also, please provide 'sudo >>> > lspci -vvvs 5:00.0' so we can see the device resources. Thanks, >>> >>> The simpletrace output wouldn't parse for me using the python script >>> (I'll paste the trace at the end of this email), so I used the ftrace >>> backend instead ( >>> https://drive.google.com/open?id=0Bwjufq6oAZMfMVpUYTUxODR0NW8 ). It's >>> quite large and I'm not sure what I'm looking for, so I didn't look at >>> it very carefully. >> >> That's not the right trace, that's like kvm trace or something. Try: >> >> # ./configure --enable-trace-backends=log >> >> # echo vfio_region_mmap_fault > events.txt >> >> Then add to your qemu commandline "-trace events=events.txt". You >> should get maybe a couple extra log lines per boot, not gobs of output. > > Ah, got it. Here are the relevant log lines then: > > 10203@1475810801.243686:vfio_region_mmap_fault Region 0000:05:00.0 BAR > 2 mmaps[0], [20000000000 - 1ffffffffff], fault: -22 > qemu-system-x86_64: -device > vfio-pci,host=05:00.0,bus=root.1,addr=00.5: Failed to mmap > 0000:05:00.0 BAR 2. Performance may be slow
I took a look at everything again and noted this in the lspci output for the Fresco Logic USB controller: Vector table: BAR=2 offset=00000000 PBA: BAR=4 offset=00000000 Is it normal for both the Vector table and PBA to have a 0 offset? Thanks, Andrew