KVM: arm64: nv: Fix RESx behaviour of disabled FGTs with negative polarity

The Fine Grained Trap extension is pretty messy as it doesn't
consistently use the same polarity for all trap bits. A bunch
of them, added later in the life of the architecture, have a
*negative* priority.

So if these bits are disabled, they must be RES1 and not RES0.
But that's not what the code implements, making the traps for
these negative trap bits being always on instead of disabled.

Fix the relevant bits, and stick a brown paper bag on my head
for the rest of the day...

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240614125858.78361-1-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index bae8536cbf003e9b949db4df115f0a7815e55554..0acb602734826a092769e41de08b21dedc1a3d06 100644 (file)
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -328,21 +328,21 @@ int kvm_init_nv_sysregs(struct kvm *kvm)
                         HFGxTR_EL2_ERXPFGF_EL1 | HFGxTR_EL2_ERXPFGCTL_EL1 |
                         HFGxTR_EL2_ERXPFGCDN_EL1 | HFGxTR_EL2_ERXADDR_EL1);
        if (!kvm_has_feat(kvm, ID_AA64ISAR1_EL1, LS64, LS64_ACCDATA))
-               res0 |= HFGxTR_EL2_nACCDATA_EL1;
+               res1 |= HFGxTR_EL2_nACCDATA_EL1;
        if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, GCS, IMP))
-               res0 |= (HFGxTR_EL2_nGCS_EL0 | HFGxTR_EL2_nGCS_EL1);
+               res1 |= (HFGxTR_EL2_nGCS_EL0 | HFGxTR_EL2_nGCS_EL1);
        if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, SME, IMP))
-               res0 |= (HFGxTR_EL2_nSMPRI_EL1 | HFGxTR_EL2_nTPIDR2_EL0);
+               res1 |= (HFGxTR_EL2_nSMPRI_EL1 | HFGxTR_EL2_nTPIDR2_EL0);
        if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, THE, IMP))
-               res0 |= HFGxTR_EL2_nRCWMASK_EL1;
+               res1 |= HFGxTR_EL2_nRCWMASK_EL1;
        if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, S1PIE, IMP))
-               res0 |= (HFGxTR_EL2_nPIRE0_EL1 | HFGxTR_EL2_nPIR_EL1);
+               res1 |= (HFGxTR_EL2_nPIRE0_EL1 | HFGxTR_EL2_nPIR_EL1);
        if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, S1POE, IMP))
-               res0 |= (HFGxTR_EL2_nPOR_EL0 | HFGxTR_EL2_nPOR_EL1);
+               res1 |= (HFGxTR_EL2_nPOR_EL0 | HFGxTR_EL2_nPOR_EL1);
        if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, S2POE, IMP))
-               res0 |= HFGxTR_EL2_nS2POR_EL1;
+               res1 |= HFGxTR_EL2_nS2POR_EL1;
        if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, AIE, IMP))
-               res0 |= (HFGxTR_EL2_nMAIR2_EL1 | HFGxTR_EL2_nAMAIR2_EL1);
+               res1 |= (HFGxTR_EL2_nMAIR2_EL1 | HFGxTR_EL2_nAMAIR2_EL1);
        set_sysreg_masks(kvm, HFGRTR_EL2, res0 | __HFGRTR_EL2_RES0, res1);
        set_sysreg_masks(kvm, HFGWTR_EL2, res0 | __HFGWTR_EL2_RES0, res1);
 
@@ -378,10 +378,10 @@ int kvm_init_nv_sysregs(struct kvm *kvm)
                         HDFGRTR_EL2_TRBPTR_EL1 | HDFGRTR_EL2_TRBSR_EL1 |
                         HDFGRTR_EL2_TRBTRG_EL1);
        if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, BRBE, IMP))
-               res0 |= (HDFGRTR_EL2_nBRBIDR | HDFGRTR_EL2_nBRBCTL |
+               res1 |= (HDFGRTR_EL2_nBRBIDR | HDFGRTR_EL2_nBRBCTL |
                         HDFGRTR_EL2_nBRBDATA);
        if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, PMSVer, V1P2))
-               res0 |= HDFGRTR_EL2_nPMSNEVFR_EL1;
+               res1 |= HDFGRTR_EL2_nPMSNEVFR_EL1;
        set_sysreg_masks(kvm, HDFGRTR_EL2, res0 | HDFGRTR_EL2_RES0, res1);
 
        /* Reuse the bits from the read-side and add the write-specific stuff */
@@ -417,9 +417,9 @@ int kvm_init_nv_sysregs(struct kvm *kvm)
                res0 |= (HFGITR_EL2_CFPRCTX | HFGITR_EL2_DVPRCTX |
                         HFGITR_EL2_CPPRCTX);
        if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, BRBE, IMP))
-               res0 |= (HFGITR_EL2_nBRBINJ | HFGITR_EL2_nBRBIALL);
+               res1 |= (HFGITR_EL2_nBRBINJ | HFGITR_EL2_nBRBIALL);
        if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, GCS, IMP))
-               res0 |= (HFGITR_EL2_nGCSPUSHM_EL1 | HFGITR_EL2_nGCSSTR_EL1 |
+               res1 |= (HFGITR_EL2_nGCSPUSHM_EL1 | HFGITR_EL2_nGCSSTR_EL1 |
                         HFGITR_EL2_nGCSEPP);
        if (!kvm_has_feat(kvm, ID_AA64ISAR1_EL1, SPECRES, COSP_RCTX))
                res0 |= HFGITR_EL2_COSPRCTX;