On 12/01/2014 11:09 PM, Michael Ellerman wrote: > On Mon, 2014-12-01 at 09:41 -0600, Nathan Fontenot wrote: >> On 11/26/2014 09:12 PM, Benjamin Herrenschmidt wrote: >>> Hi Greg, >>> >>> So Nathan is working on a patch series to cleanup and improve our >>> "DLPAR" infrastructure which is basically our hotplug mechanism when >>> running under the PowerVM (aka pHyp) and KVM hypervisors. >> >> The cleanup to the dlpar infrastructure will move the entire operation >> of hotplugging a device to the kernel instead of doing it partially in >> userspace and partially in the kernel as is currently done. >> > ... >> >> For PowerVM systems we need this sysfs file to deliver what is >> essentially a binary blob (specifically a rtas error log) to the >> kernel. > > Those two statements don't really agree with each other. ie. "move the entire > operation .. to the kernel", but then we need a sysfs file so userspace can > deliver us a blob? > > I think what you mean is that all the actual logic will move into the kernel, > and the only thing userspace will do (on PowerVM) is write the blog to kick > off > the process. > > On PowerKVM the entire process will be handled in the kernel (after some > additional patches to hook up the rtas event to the hotplug). >
This is correct. I should have explained it better. > > As ugly as it is, we already have /proc/rtas, which includes a bunch of files, > including error_log, which is where you can *read* the RTAS error logs from. > I have no problem making this a writeable file. I think keeping all of the rtas error log communication between the kernel userspace in one place would be a good idea. > So maybe we just extend that, either a new file, or just by making error_log > writable? > > It'd be nice to drop all that rtas gunk and move to something cleaner in /sys, > but I don't think we can realistically do that any time soon anyway? > Perhaps doing this at a later time would be worthwhile. -Nathan _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
