| Message ID | 20241009190019.3222687-21-maz@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: arm64: Add EL2 support to FEAT_S1PIE/S1POE | expand |
On Wed, Oct 09, 2024 at 08:00:03PM +0100, Marc Zyngier wrote: > S1PIE implicitly disables hierarchical permissions, as specified in > R_JHSVW, by making TCR_ELx.HPDn RES1. > > Add a predicate for S1PIE being enabled for a given translation regime, > and emulate this behaviour by forcing the hpd field to true if S1PIE > is enabled for that translation regime. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > arch/arm64/kvm/at.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c > index adcfce3f67f03..f5bd750288ff5 100644 > --- a/arch/arm64/kvm/at.c > +++ b/arch/arm64/kvm/at.c > @@ -93,6 +93,23 @@ static enum trans_regime compute_translation_regime(struct kvm_vcpu *vcpu, u32 o > } > } > > +static bool s1pie_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime) > +{ > + if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR3_EL1, S1PIE, IMP)) > + return false; > + > + switch (regime) { > + case TR_EL2: > + case TR_EL20: > + return vcpu_read_sys_reg(vcpu, TCR2_EL2) & TCR2_EL2_PIE; > + case TR_EL10: > + return (__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En) && > + (__vcpu_sys_reg(vcpu, TCR2_EL1) & TCR2_EL1x_PIE); > + default: > + BUG(); BUILD_BUG()? > + } > +} > + > static int setup_s1_walk(struct kvm_vcpu *vcpu, u32 op, struct s1_walk_info *wi, > struct s1_walk_result *wr, u64 va) > { > @@ -186,6 +203,8 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, u32 op, struct s1_walk_info *wi, > (va55 ? > FIELD_GET(TCR_HPD1, tcr) : > FIELD_GET(TCR_HPD0, tcr))); > + /* R_JHSVW */ > + wi->hpd |= s1pie_enabled(vcpu, wi->regime); > > /* Someone was silly enough to encode TG0/TG1 differently */ > if (va55) { > -- > 2.39.2 >
On Thu, 10 Oct 2024 08:33:13 +0100, Oliver Upton <oliver.upton@linux.dev> wrote: > > On Wed, Oct 09, 2024 at 08:00:03PM +0100, Marc Zyngier wrote: > > S1PIE implicitly disables hierarchical permissions, as specified in > > R_JHSVW, by making TCR_ELx.HPDn RES1. > > > > Add a predicate for S1PIE being enabled for a given translation regime, > > and emulate this behaviour by forcing the hpd field to true if S1PIE > > is enabled for that translation regime. > > > > Signed-off-by: Marc Zyngier <maz@kernel.org> > > --- > > arch/arm64/kvm/at.c | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c > > index adcfce3f67f03..f5bd750288ff5 100644 > > --- a/arch/arm64/kvm/at.c > > +++ b/arch/arm64/kvm/at.c > > @@ -93,6 +93,23 @@ static enum trans_regime compute_translation_regime(struct kvm_vcpu *vcpu, u32 o > > } > > } > > > > +static bool s1pie_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime) > > +{ > > + if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR3_EL1, S1PIE, IMP)) > > + return false; > > + > > + switch (regime) { > > + case TR_EL2: > > + case TR_EL20: > > + return vcpu_read_sys_reg(vcpu, TCR2_EL2) & TCR2_EL2_PIE; > > + case TR_EL10: > > + return (__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En) && > > + (__vcpu_sys_reg(vcpu, TCR2_EL1) & TCR2_EL1x_PIE); > > + default: > > + BUG(); > > BUILD_BUG()? Doesn't work. regime is fished out of the walk_info structure, meaning that it is pretty opaque to the compiler, which in turn needs to emit code for all cases. Thanks, M.
diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c index adcfce3f67f03..f5bd750288ff5 100644 --- a/arch/arm64/kvm/at.c +++ b/arch/arm64/kvm/at.c @@ -93,6 +93,23 @@ static enum trans_regime compute_translation_regime(struct kvm_vcpu *vcpu, u32 o } } +static bool s1pie_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime) +{ + if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR3_EL1, S1PIE, IMP)) + return false; + + switch (regime) { + case TR_EL2: + case TR_EL20: + return vcpu_read_sys_reg(vcpu, TCR2_EL2) & TCR2_EL2_PIE; + case TR_EL10: + return (__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En) && + (__vcpu_sys_reg(vcpu, TCR2_EL1) & TCR2_EL1x_PIE); + default: + BUG(); + } +} + static int setup_s1_walk(struct kvm_vcpu *vcpu, u32 op, struct s1_walk_info *wi, struct s1_walk_result *wr, u64 va) { @@ -186,6 +203,8 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, u32 op, struct s1_walk_info *wi, (va55 ? FIELD_GET(TCR_HPD1, tcr) : FIELD_GET(TCR_HPD0, tcr))); + /* R_JHSVW */ + wi->hpd |= s1pie_enabled(vcpu, wi->regime); /* Someone was silly enough to encode TG0/TG1 differently */ if (va55) {
S1PIE implicitly disables hierarchical permissions, as specified in R_JHSVW, by making TCR_ELx.HPDn RES1. Add a predicate for S1PIE being enabled for a given translation regime, and emulate this behaviour by forcing the hpd field to true if S1PIE is enabled for that translation regime. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/at.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)