diff options
| author | Marc Zyngier <maz@kernel.org> | 2023-02-09 20:58:17 +0300 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2023-02-11 13:13:29 +0300 |
| commit | e6b367db0f9192692a3f3057878f1259fe966d33 (patch) | |
| tree | 243a7c2e9d72fca95eea58571cb9b25fd062c4c3 /arch/arm64/kvm/sys_regs.h | |
| parent | d9552fe133f9f7c357460b041e2d3b20310adf8d (diff) | |
| download | linux-e6b367db0f9192692a3f3057878f1259fe966d33.tar.xz | |
KVM: arm64: nv: Allow a sysreg to be hidden from userspace only
So far, we never needed to distinguish between registers hidden
from userspace and being hidden from a guest (they are always
either visible to both, or hidden from both).
With NV, we have the ugly case of the EL02 and EL12 registers,
which are only a view on the EL0 and EL1 registers. It makes
absolutely no sense to expose them to userspace, since it
already has the canonical view.
Add a new visibility flag (REG_HIDDEN_USER) and a new helper that
checks for it and REG_HIDDEN when checking whether to expose
a sysreg to userspace. Subsequent patches will make use of it.
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230209175820.1939006-16-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Diffstat (limited to 'arch/arm64/kvm/sys_regs.h')
| -rw-r--r-- | arch/arm64/kvm/sys_regs.h | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index e4ebb3a379fd..6b11f2cc7146 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -85,8 +85,9 @@ struct sys_reg_desc { }; #define REG_HIDDEN (1 << 0) /* hidden from userspace and guest */ -#define REG_RAZ (1 << 1) /* RAZ from userspace and guest */ -#define REG_USER_WI (1 << 2) /* WI from userspace only */ +#define REG_HIDDEN_USER (1 << 1) /* hidden from userspace only */ +#define REG_RAZ (1 << 2) /* RAZ from userspace and guest */ +#define REG_USER_WI (1 << 3) /* WI from userspace only */ static __printf(2, 3) inline void print_sys_reg_msg(const struct sys_reg_params *p, @@ -152,6 +153,15 @@ static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu, return sysreg_visibility(vcpu, r) & REG_HIDDEN; } +static inline bool sysreg_hidden_user(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) +{ + if (likely(!r->visibility)) + return false; + + return r->visibility(vcpu, r) & (REG_HIDDEN | REG_HIDDEN_USER); +} + static inline bool sysreg_visible_as_raz(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { |