| Message ID | 20220528113829.1043361-16-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM/arm64: Refactoring the vcpu flags | expand |
Hi Marc, On Sat, May 28, 2022 at 12:49 PM Marc Zyngier <maz@kernel.org> wrote: > > We really don't want PENDING_EXCEPTION and INCREMENT_PC to ever be > set at the same time, as they are mutually exclusive. Add checks > that will generate a warning should this ever happen. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > arch/arm64/include/asm/kvm_emulate.h | 1 + > arch/arm64/kvm/hyp/nvhe/sys_regs.c | 2 ++ > arch/arm64/kvm/inject_fault.c | 8 ++++++++ > 3 files changed, 11 insertions(+) > > diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h > index 46e631cd8d9e..861fa0b24a7f 100644 > --- a/arch/arm64/include/asm/kvm_emulate.h > +++ b/arch/arm64/include/asm/kvm_emulate.h > @@ -473,6 +473,7 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu, > > static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu) > { > + WARN_ON(vcpu_get_flag(vcpu, PENDING_EXCEPTION)); > vcpu_set_flag(vcpu, INCREMENT_PC); > } > > diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > index 2841a2d447a1..04973984b6db 100644 > --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c > +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > @@ -38,6 +38,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) > *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR); > *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR); > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > + > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); > > diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c > index a9a7b513f3b0..2f4b9afc16ec 100644 > --- a/arch/arm64/kvm/inject_fault.c > +++ b/arch/arm64/kvm/inject_fault.c > @@ -20,6 +20,8 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr > bool is_aarch32 = vcpu_mode_is_32bit(vcpu); > u32 esr = 0; > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > + Minor nit: While we're at it, should we just create a helper for setting PENDING_EXCEPTION, same as we have for INCREMENT_PC? That might make the code clearer and save us from the hassle of having this WARN_ON before every instance of setting PENDING_EXCEPTION? Cheers, /fuad > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); > > @@ -51,6 +53,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) > { > u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > + > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); > > @@ -71,6 +75,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) > > static void inject_undef32(struct kvm_vcpu *vcpu) > { > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > + > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > vcpu_set_flag(vcpu, EXCEPT_AA32_UND); > } > @@ -94,6 +100,8 @@ static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, u32 addr) > > far = vcpu_read_sys_reg(vcpu, FAR_EL1); > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > + > if (is_pabt) { > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > vcpu_set_flag(vcpu, EXCEPT_AA32_IABT); > -- > 2.34.1 >
On Wed, 08 Jun 2022 16:16:55 +0100, Fuad Tabba <tabba@google.com> wrote: > > Hi Marc, > > On Sat, May 28, 2022 at 12:49 PM Marc Zyngier <maz@kernel.org> wrote: > > > > We really don't want PENDING_EXCEPTION and INCREMENT_PC to ever be > > set at the same time, as they are mutually exclusive. Add checks > > that will generate a warning should this ever happen. > > > > Signed-off-by: Marc Zyngier <maz@kernel.org> > > --- > > arch/arm64/include/asm/kvm_emulate.h | 1 + > > arch/arm64/kvm/hyp/nvhe/sys_regs.c | 2 ++ > > arch/arm64/kvm/inject_fault.c | 8 ++++++++ > > 3 files changed, 11 insertions(+) > > > > diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h > > index 46e631cd8d9e..861fa0b24a7f 100644 > > --- a/arch/arm64/include/asm/kvm_emulate.h > > +++ b/arch/arm64/include/asm/kvm_emulate.h > > @@ -473,6 +473,7 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu, > > > > static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu) > > { > > + WARN_ON(vcpu_get_flag(vcpu, PENDING_EXCEPTION)); > > vcpu_set_flag(vcpu, INCREMENT_PC); > > } > > > > diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > > index 2841a2d447a1..04973984b6db 100644 > > --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c > > +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > > @@ -38,6 +38,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) > > *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR); > > *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR); > > > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > > + > > vcpu_set_flag(vcpu, PENDING_EXCEPTION); > > vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); > > > > diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c > > index a9a7b513f3b0..2f4b9afc16ec 100644 > > --- a/arch/arm64/kvm/inject_fault.c > > +++ b/arch/arm64/kvm/inject_fault.c > > @@ -20,6 +20,8 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr > > bool is_aarch32 = vcpu_mode_is_32bit(vcpu); > > u32 esr = 0; > > > > + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); > > + > > Minor nit: While we're at it, should we just create a helper for > setting PENDING_EXCEPTION, same as we have for INCREMENT_PC? That > might make the code clearer and save us from the hassle of having this > WARN_ON before every instance of setting PENDING_EXCEPTION? Good point. I ended up with this: #define kvm_pend_exception(v, e) \ do { \ WARN_ON(vcpu_get_flag((v), INCREMENT_PC)); \ vcpu_set_flag((v), PENDING_EXCEPTION); \ vcpu_set_flag((v), e); \ } while (0) It has to be a macro in order to deal with the flag expansion, but is otherwise a welcome cleanup. Thanks, M.
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 46e631cd8d9e..861fa0b24a7f 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -473,6 +473,7 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu, static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu) { + WARN_ON(vcpu_get_flag(vcpu, PENDING_EXCEPTION)); vcpu_set_flag(vcpu, INCREMENT_PC); } diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c index 2841a2d447a1..04973984b6db 100644 --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c @@ -38,6 +38,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR); *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR); + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); + vcpu_set_flag(vcpu, PENDING_EXCEPTION); vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index a9a7b513f3b0..2f4b9afc16ec 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -20,6 +20,8 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr bool is_aarch32 = vcpu_mode_is_32bit(vcpu); u32 esr = 0; + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); + vcpu_set_flag(vcpu, PENDING_EXCEPTION); vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); @@ -51,6 +53,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) { u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); + vcpu_set_flag(vcpu, PENDING_EXCEPTION); vcpu_set_flag(vcpu, EXCEPT_AA64_EL1_SYNC); @@ -71,6 +75,8 @@ static void inject_undef64(struct kvm_vcpu *vcpu) static void inject_undef32(struct kvm_vcpu *vcpu) { + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); + vcpu_set_flag(vcpu, PENDING_EXCEPTION); vcpu_set_flag(vcpu, EXCEPT_AA32_UND); } @@ -94,6 +100,8 @@ static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, u32 addr) far = vcpu_read_sys_reg(vcpu, FAR_EL1); + WARN_ON(vcpu_get_flag(vcpu, INCREMENT_PC)); + if (is_pabt) { vcpu_set_flag(vcpu, PENDING_EXCEPTION); vcpu_set_flag(vcpu, EXCEPT_AA32_IABT);
We really don't want PENDING_EXCEPTION and INCREMENT_PC to ever be set at the same time, as they are mutually exclusive. Add checks that will generate a warning should this ever happen. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/include/asm/kvm_emulate.h | 1 + arch/arm64/kvm/hyp/nvhe/sys_regs.c | 2 ++ arch/arm64/kvm/inject_fault.c | 8 ++++++++ 3 files changed, 11 insertions(+)