diff mbox series

[v5,1/6] KVM: arm64: Correctly treat writes to OSLSR_EL1 as undefined

Message ID 20220203174159.2887882-2-oupton@google.com (mailing list archive)
State New, archived
Headers show
Series KVM: arm64: Emulate the OS Lock | expand

Commit Message

Oliver Upton Feb. 3, 2022, 5:41 p.m. UTC 
Writes to OSLSR_EL1 are UNDEFINED and should never trap from EL1 to
EL2, but the kvm trap handler for OSLSR_EL1 handles writes via
ignore_write(). This is confusing to readers of code, but should have
no functional impact.

For clarity, use write_to_read_only() rather than ignore_write(). If a
trap is unexpectedly taken to EL2 in violation of the architecture, this
will WARN_ONCE() and inject an undef into the guest.

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
[adopted Mark's changelog suggestion, thanks!]
Signed-off-by: Oliver Upton <oupton@google.com>
---
 arch/arm64/kvm/sys_regs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 4dc2fba316ff..85208acd273d 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -292,7 +292,7 @@  static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
 			   const struct sys_reg_desc *r)
 {
 	if (p->is_write) {
-		return ignore_write(vcpu, p);
+		return write_to_read_only(vcpu, p, r);
 	} else {
 		p->regval = (1 << 3);
 		return true;