On Mon, Mar 18, 2024 at 04:57:52PM -0500, Tom Zanussi wrote: > Hi Jerry, > > On Mon, 2024-03-18 at 13:35 -0700, Jerry Snitselaar wrote: > > On Mon, Mar 18, 2024 at 01:18:58AM -0700, Jerry Snitselaar wrote: > > > With adding the support for loading external drivers like iaa, > > > autoloading, and default configs, systems with IAA that are booted > > > in > > > legacy mode get a number of probe failing messages from the user > > > driver for the iax wqs before it probes with the iaa_crypto > > > driver. Should the name match check occur prior to checking if user > > > pasid is enabled in idxd_user_drv_probe? On a GNR system this will > > > generate over 100 log messages at boot like the following: > > > > > > [ 56.885504] user: probe of wq15.0 failed with error -95 > > > > > > Regards, > > > Jerry > > > > > > > Hi Tom, > > > > A couple more iaa questions I had: > > > > - Are you supposed to disable all iax workqueues/devices to > > reconfigure a workqueue? It seems perfectly happy to let you > > disable, reconfigure, and enable just one. I know for idxd in > > general the intent is to be able to disable, configure, and enable > > workqueues/devices as needed for different users. I'm wondering if > > that is the case for iaa as well since it talks about unloading and > > loading iaa_crypto for new configurations. > > > > In general the idea is that you set up your workqueues/devices, which > registers the iaa-crypto algorithm and makes it available as a plugin > to e.g. zswap. The register happens on the probe of the first wq, > subsequent wqs are added after that and rebalance the wq table, so > yeah, you can also reconfigure wqs in the same way. > > But you can't remove and reconfigure everything and re-register the > algorithm, see below. > > > > > - Is there a reason that iaa_crypto needs to be reloaded beyond the > > compression algorithm registration? I tried moving the unregister > > into iaa_crypto_remove with a check that the iaa_devices list is > > empty, and it seemed to work, but I wasn't sure if there some other > > reason for it being in iaa_crypto_cleanup_module instead of > > iaa_crypto_remove similar to the register call in iaa_crypto_probe. > > > > The requirement to only allow the algorithm to be unregistered on > module unload came from the crypto maintainer during review [1]. > > Specifically, this part: > > 1) Never unregister your crypto algorithms, even after the last > piece of hardware has been unplugged. The algorithms should only > be unregistered (if they have been registered through the first > successful probe call) in the module unload function. > > hth, > > Tom > > > [1] https://lore.kernel.org/lkml/ZC58JggIXgpJ1tpD@xxxxxxxxxxxxxxxxxxx/ > > Thank you for the explanation and information Tom. Regards, Jerry > > > > > Regards, > > Jerry > > >
