Hi Miguel, On 6/6/23 19:52, Miguel Luis wrote: > Hello Eric, Marc, > >> On 6 Jun 2023, at 09:33, Eric Auger <eauger@xxxxxxxxxx> wrote: >> >> Hi Marc, >> >> On 5/17/23 16:12, Marc Zyngier wrote: >>> On Wed, 17 May 2023 09:59:45 +0100, >>> Eric Auger <eauger@xxxxxxxxxx> wrote: >>>> >>>> Hi Marc, >>>> Hi Marc, >>>> On 5/16/23 22:28, Marc Zyngier wrote: >>>>> On Tue, 16 May 2023 17:53:14 +0100, >>>>> Eric Auger <eauger@xxxxxxxxxx> wrote: >>>>>> >>>>>> Hi Marc, >>>>>> >>>>>> On 5/15/23 19:30, Marc Zyngier wrote: >>>>>>> This is the 4th drop of NV support on arm64 for this year. >>>>>>> >>>>>>> For the previous episodes, see [1]. >>>>>>> >>>>>>> What's changed: >>>>>>> >>>>>>> - New framework to track system register traps that are reinjected in >>>>>>> guest EL2. It is expected to replace the discrete handling we have >>>>>>> enjoyed so far, which didn't scale at all. This has already fixed a >>>>>>> number of bugs that were hidden (a bunch of traps were never >>>>>>> forwarded...). Still a work in progress, but this is going in the >>>>>>> right direction. >>>>>>> >>>>>>> - Allow the L1 hypervisor to have a S2 that has an input larger than >>>>>>> the L0 IPA space. This fixes a number of subtle issues, depending on >>>>>>> how the initial guest was created. >>>>>>> >>>>>>> - Consequently, the patch series has gone longer again. Boo. But >>>>>>> hopefully some of it is easier to review... >>>>>>> >>>>>>> [1] https://lore.kernel.org/r/20230405154008.3552854-1-maz@xxxxxxxxxx >>>>>> >>>>>> I have started testing this and when booting my fedora guest I get >>>>>> >>>>>> [ 151.796544] kvm [7617]: Unsupported guest sys_reg access at: >>>>>> 23f425fd0 [80000209] >>>>>> [ 151.796544] { Op0( 3), Op1( 3), CRn(14), CRm( 3), Op2( 1), func_write }, >>>>>> >>>>>> as soon as the host has kvm-arm.mode=nested >>>>>> >>>>>> This seems to be triggered very early by EDK2 >>>>>> (ArmPkg/Drivers/TimerDxe/TimerDxe.c). >>>>>> >>>>>> If I am not wrong this CNTV_CTL_EL0. Do you have any idea? >>>>> >>>>> So here's my current analysis: >>>>> >>>>> I assume you are running EDK2 as the L1 guest in a nested >>>>> configuration. I also assume that you are not running on an Apple >>>>> CPU. If these assumptions are correct, then EDK2 runs at vEL2, and is >>>>> in nVHE mode. >>>>> >>>>> Finally, I'm going to assume that your implementation has FEAT_ECV and >>>>> FEAT_NV2, because I can't see how it could fail otherwise. >>>> all the above is correct. >>>>> >>>>> In these precise conditions, KVM sets the CNTHCTL_EL2.EL1TVT bit so >>>>> that we can trap the EL0 virtual timer and faithfully emulate it (it >>>>> is otherwise written to memory, which isn't very helpful). >>>> >>>> indeed >>>>> >>>>> As it turns out, we don't handle these traps. I didn't spot it because >>>>> my test machines are all Apple boxes that don't have a nVHE mode, so >>>>> nothing on the nVHE path is getting *ANY* coverage. Hint: having >>>>> access to such a machine would help (shipping address on request!). >>>>> Otherwise, I'll eventually kill the nVHE support altogether. >>>>> >>>>> I have written the following patch, which compiles, but that I cannot >>>>> test with my current setup. Could you please give it a go? >>>> >>>> with the patch below, my guest boots nicely. You did it great on the 1st >>>> shot!!! So this fixes my issue. I will continue testing the v10. >>> >>> Thanks a lot for reporting the issue and testing my hacks. I'll >>> eventually fold it into the rest of the series. >>> >>> By the way, what are you using as your VMM? I'd really like to >>> reproduce your setup. >> Sorry I missed your reply. I am using libvirt + qemu (feat Miguel's RFC) >> and fedora L1 guest. >> > > Following this subject, I’ve forward ported Alexandru’s KUT patches > ( and I encourage others to do it also =) ) which expose an EL2 test that Do you have a branch available with Alexandru's rebased kut series? Thanks Eric > does three checks: > > - whether VHE is supported and enabled > - disable VHE > - re-enable VHE > > I’m running qemu with virtualization=on as well to run this test and it is passing although > problems seem to happen when running with virtualization=off, which I’m still looking into it. > > Thanks > Miguel > >> Thanks to your fix, this boots fine. But at the moment it does not >> reboot and hangs in edk2 I think. Unfortunately this time I have no >> trace on host :-( While looking at your series I will add some traces. >> >> Eric >>> >>> Cheers, >>> >>> M. > >
