[PATCH] RISC-V: KVM: Redirect instruction access fault trap to guest

From: zhouquan
Date: Thu Aug 29 2024 - 02:21:07 EST


From: Quan Zhou <zhouquan@xxxxxxxxxxx>

The M-mode redirects an unhandled instruction access
fault trap back to S-mode when not delegating it to
VS-mode(hedeleg). However, KVM running in HS-mode
terminates the VS-mode software when back from M-mode.

The KVM should redirect the trap back to VS-mode, and
let VS-mode trap handler decide the next step.

Signed-off-by: Quan Zhou <zhouquan@xxxxxxxxxxx>
---
arch/riscv/kvm/vcpu_exit.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
index fa98e5c024b2..696b62850d0b 100644
--- a/arch/riscv/kvm/vcpu_exit.c
+++ b/arch/riscv/kvm/vcpu_exit.c
@@ -182,6 +182,7 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
ret = -EFAULT;
run->exit_reason = KVM_EXIT_UNKNOWN;
switch (trap->scause) {
+ case EXC_INST_ACCESS:
case EXC_INST_ILLEGAL:
case EXC_LOAD_MISALIGNED:
case EXC_STORE_MISALIGNED:

base-commit: 7c626ce4bae1ac14f60076d00eafe71af30450ba
--
2.34.1