On 13-08-11 08:40 PM, Guenter Roeck wrote: > On 08/11/2013 03:04 PM, Russell King - ARM Linux wrote: >> On Sun, Aug 11, 2013 at 08:54:43AM -0700, Guenter Roeck wrote: >>> Hi, >>> >>> trying to boot arm versatile images with qemu results in the following error >>> if I try to boot with a disk image. >>> >>> sym0: <895a> rev 0x0 at pci 0000:00:0d.0 irq 92 >>> sym0: SCSI BUS has been reset. >>> scsi0 : sym-2.2.3 >>> [...] >>> scsi 0:0:0:0: ABORT operation started >>> scsi 0:0:0:0: ABORT operation timed-out. >>> [...] >>> >>> Yocto's 3.8 kernel images work, upstream kernels 3.8 and later fail >>> (I did not check if/how earlier kernels are affected). >>> >>> Tracking this down shows that the problem is known and has been fixed with >>> commit 351d1339 (arm: add dummy swizzle for versatile with qemu) in the >>> Yocto 3.8 kernel at git://git.yoctoproject.org/linux-yocto-3.8. >>> >>> Would it be possible to submit this patch for inclusion into affected >>> upstream kernels ? >> >> It could be that it's qemu's PCI routing is wrong - it's not the first >> time that qemu has got something wrong. >> >> Unfortunately, the PCI routing is totally undocumented, and as I understand >> it, there's very few backplanes out there now that finding out their real >> routing is virtually impossible. I'm loathed to change it unless someone >> can point to a definitive source of information on this. >> > > Maybe Paul can comment, as he wrote the patch.
If I recall correctly, I'd showed the patch to Russell at the time (via IRC, I believe) and he'd told me essentially the same thing as the above paragraph, which is why I didn't put it in the patch system, and why the commit log of the yocto patch (http://goo.gl/riEZXY) reads as it does (i.e. it is unclear what the real swizzle is). If docs appear that help clarify where the real issue is, then great. Paul. -- > > If it helps, I tried with qemu 1.4.0 from Ubuntu 13.4, qemu 1.4.0 from Poky > 1.4.0-1, > and qemu 1.5.2 from the qemu repository. > > Copying qemu-devel to increase the audience. > > Guenter >
