On Thu, 16 Apr 2020 11:37:21 +0200 Cornelia Huck <cohuck@xxxxxxxxxx> wrote: > On Wed, 15 Apr 2020 13:10:10 -0400 > Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote: > > > On 4/14/20 8:58 AM, Cornelia Huck wrote: > > > On Tue, 7 Apr 2020 15:20:03 -0400 > > > Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote: > > > >> + > > >> + if (ap_drv->in_use) > > >> + if (ap_drv->in_use(newapm, ap_perms.aqm)) > > > Can we log the offending apm somewhere, preferably with additional info > > > that allows the admin to figure out why an error was returned? > > > > One of the things on my TODO list is to add logging to the vfio_ap > > module which will track all significant activity within the device > > driver. I plan to do that with a patch or set of patches specifically > > put together for that purpose. Having said that, the best place to > > log this would be in the in_use callback in the vfio_ap device driver > > (see next patch) where the APQNs that are in use can be identified. > > For now, I will log a message to the dmesg log indicating which > > APQNs are in use by the matrix mdev. > > Sounds reasonable. My main issue was what an admin was supposed to do > until logging was in place :) Logging may not be the right answer here. Imagine somebody wants to build a nice web-tool for managing this stuff at scale -- e.g. something HMC. I don't think the solution is to let this tool parse the kernel messages and try to relate that to its own transactions. But I do agree, having a way to report why "won't do" to the end user is important for usability. Regards, Halil > > > > > > > > >> + rc = -EADDRINUSE; > > >> + > > >> + module_put(drv->owner); > > >> + > > >> + return rc; > > >> +} >