arm: KVM: Make unexpected register accesses inject an undef

Reads from write-only system registers are generally confined to
EL1 and not propagated to EL2 (that's what the architecture
mantates). In order to be sure that we have a sane behaviour
even in the unlikely event that we have a broken system, we still
handle it in KVM. Same goes for write to RO registers.

In that case, let's inject an undef into the guest.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This commit is contained in:
Marc Zyngier 2017-03-27 17:03:44 +01:00 committed by Christoffer Dall
parent b6b7a8069d
commit b1d4cb6983
2 changed files with 18 additions and 18 deletions

View File

@ -40,6 +40,24 @@
* Co-processor emulation
*****************************************************************************/
static bool write_to_read_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
WARN_ONCE(1, "CP15 write to read-only register\n");
print_cp_instr(params);
kvm_inject_undefined(vcpu);
return false;
}
static bool read_from_write_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
WARN_ONCE(1, "CP15 read to write-only register\n");
print_cp_instr(params);
kvm_inject_undefined(vcpu);
return false;
}
/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
static u32 cache_levels;

View File

@ -81,24 +81,6 @@ static inline bool read_zero(struct kvm_vcpu *vcpu,
return true;
}
static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
kvm_debug("CP15 write to read-only register at: %08lx\n",
*vcpu_pc(vcpu));
print_cp_instr(params);
return false;
}
static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
kvm_debug("CP15 read to write-only register at: %08lx\n",
*vcpu_pc(vcpu));
print_cp_instr(params);
return false;
}
/* Reset functions */
static inline void reset_unknown(struct kvm_vcpu *vcpu,
const struct coproc_reg *r)