James Bottomley @ 2020-10-13 08:24 MST: > On Tue, 2020-10-13 at 08:15 -0700, Jerry Snitselaar wrote: >> Jarkko Sakkinen @ 2020-10-12 18:17 MST: >> >> > On Thu, Oct 01, 2020 at 11:09:20AM -0700, James Bottomley wrote: >> > > The current state of the TIS TPM is that interrupts have been >> > > globally disabled by various changes. The problems we got >> > > reported the last time they were enabled was interrupt >> > > storms. With my own TIS TPM, I've found that this is caused >> > > because my TPM doesn't do legacy cycles, The TIS spec (chapter >> > > 6.1 "Locality Usage Per Register") requires any TIS TPM without >> > > legacy cycles not to act on any write to an interrupt register >> > > unless the locality is enabled. This means if an interrupt fires >> > > after we relinquish the locality, the TPM_EOI in the interrupt >> > > routine is ineffective meaning the same interrupt triggers over >> > > and over again. This problem also means we can have trouble >> > > setting up interrupts on TIS TPMs because the current init >> > > code does the setup before the locality is claimed for the first >> > > time. >> > > >> > > James >> > >> > You should consider expanding the audience. > > Well, most people interested in testing this sort of thing are already > on the integrity list. > >> > Jerry, once you have some bandwidth (no rush, does not land before >> > rc2), it would be great that if you could try this. I'm emphasizing >> > this just because of the intersection. I think it would also make >> > senset to get tested-by from Nayna. >> >> I will run some tests on some other systems I have access to. As >> noted in the other email I did a quick test with a t490s with an >> older bios that exhibits the problem originally reported when >> Stefan's patch enabled interrupts. > > Well, it means there's still some other problem. I was hoping that > because the rainbow pass system originally exhibited the same symptoms > (interrupt storm) fixing it would also fix the t490 and the ineffective > EOI bug looked like a great candidate for being the root cause. > Adding Hans to the list. IIUC in the t490s case the problem lies with the hardware itself. Hans, is that correct? > How amenable are you to debugging this? I originally figured out the > problem with the rainbow pass by putting ratelimited printks in the > interrupt routine and most of the TIS transmission ones, but it's > somewhat labour intensive doing it this way. > > James
