On Tue, 21 Nov 2023 16:49:52 +0000, Miguel Luis <miguel.luis@xxxxxxxxxx> wrote: > > Hi Marc, > > > On 20 Nov 2023, at 12:09, Marc Zyngier <maz@xxxxxxxxxx> wrote: > > > > This is the 5th drop of NV support on arm64 for this year, and most > > probably the last one for this side of Christmas. > > > > For the previous episodes, see [1]. > > > > What's changed: > > > > - Drop support for the original FEAT_NV. No existing hardware supports > > it without FEAT_NV2, and the architecture is deprecating the former > > entirely. This results in fewer patches, and a slightly simpler > > model overall. > > > > - Reorganise the series to make it a bit more logical now that FEAT_NV > > is gone. > > > > - Apply the NV idreg restrictions on VM first run rather than on each > > access. > > > > - Make the nested vgic shadow CPU interface a per-CPU structure rather > > than per-vcpu. > > > > - Fix the EL0 timer fastpath > > > > - Work around the architecture deficiencies when trapping WFI from a > > L2 guest. > > > > - Fix sampling of nested vgic state (MISR, ELRSR, EISR) > > > > - Drop the patches that have already been merged (NV trap forwarding, > > per-MMU VTCR) > > > > - Rebased on top of 6.7-rc2 + the FEAT_E2H0 support [2]. > > > > The branch containing these patches (and more) is at [3]. As for the > > previous rounds, my intention is to take a prefix of this series into > > 6.8, provided that it gets enough reviewing. > > > > [1] https://lore.kernel.org/r/20230515173103.1017669-1-maz@xxxxxxxxxx > > [2] https://lore.kernel.org/r/20231120123721.851738-1-maz@xxxxxxxxxx > > [3] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=kvm-arm64/nv-6.8-nv2-only > > > > While I was testing this with kvmtool for 5.16 I noted the following on dmesg: > > [ 803.014258] kvm [19040]: Unsupported guest sys_reg access at: 8129fa50 [600003c9] > { Op0( 3), Op1( 5), CRn( 1), CRm( 0), Op2( 2), func_read }, > > This is CPACR_EL12. CPACR_EL12 is redirected to VNCR[0x100]. It really shouldn't trap... > Still need yet to debug. Can you disassemble the guest around the offending PC? > As for QEMU, it is having issues enabling _EL2 feature although EL2 > is supported by checking KVM_CAP_ARM_EL2; need yet to debug this. The capability number changes at each release. Make sure you resync your includes. M. -- Without deviation from the norm, progress is not possible.
