Re: 4.13.0-rc4 sparc64: can't allocate MSI-X affinity masks for 2 vectors

[Bjorn Helgaas]

On Wed, Aug 16, 2017 at 09:39:08PM +0300, Meelis Roos wrote:
> > > > I noticed that in 4.13.0-rc4 there is a new error in dmesg on my sparc64 
> > > > t5120 server: can't allocate MSI-X affinity masks.
> > > > 
> > > > [   30.274284] qla2xxx [0000:00:00.0]-0005: : QLogic Fibre Channel HBA Driver: 10.00.00.00-k.
> > > > [   30.274648] qla2xxx [0000:10:00.0]-001d: : Found an ISP2432 irq 21 iobase 0x000000c100d00000.
> > > > [   30.275447] qla2xxx 0000:10:00.0: can't allocate MSI-X affinity masks for 2 vectors
> > > > [   30.816882] scsi host1: qla2xxx
> > > > [   30.877294] qla2xxx: probe of 0000:10:00.0 failed with error -22
> > > > [   30.877578] qla2xxx [0000:10:00.1]-001d: : Found an ISP2432 irq 22 iobase 0x000000c100d04000.
> > > > [   30.878387] qla2xxx 0000:10:00.1: can't allocate MSI-X affinity masks for 2 vectors
> > > > [   31.367083] scsi host1: qla2xxx
> > > > [   31.427500] qla2xxx: probe of 0000:10:00.1 failed with error -22
> > > > 
> > > > I do not know if the driver works since nothing is attached to the FC 
> > > > HBA at the moment, but from the error messages it looks like the driver 
> > > > fails to load.
> > > > 
> > > > I booted 4.12 and 4.11 - the red error is not there but the failure 
> > > > seems to be the same error -22:
> > 
> > 4.10.0 works, 4.11.0 errors out with EINVAL and 4.13-rc4 errorr sout 
> > with more verbose MSI messages. So something between 4.10 and 4.11 has 
> > broken it.
> 
> I can not reproduice the older kernels that misbehave. I checked out 
> earlier kernels and recompiled them (old config lost, nothing changed 
> AFAIK), everything works up to 4.12 inclusive.
> 
> > Also, 4.13-rc4 is broken on another sun4v here (T1000). So it seems to 
> > be sun4v interrupt related.
> 
> This still holds - 4.13-rc4 has MSI trouble on at least 2 of my sun4v 
> machines.

IIUC, that means v4.12 works and v4.13-rc4 does not, so this is a
regression we introduced this cycle.

If nobody steps up with a theory, bisecting might be the easiest path
forward.