RISC-V: KVM: Redirect AMO load/store misaligned traps to guest

The M-mode redirects an unhandled misaligned 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.
Here is a way to handle misaligned traps in KVM,
not only directing them to VS-mode or terminate it.

Signed-off-by: wchen <waylingII@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
wchen 2023-05-20 23:01:16 +08:00 committed by Anup Patel
parent 78329084b8
commit 19bff88e65
2 changed files with 4 additions and 0 deletions

View File

@ -82,7 +82,9 @@
#define EXC_INST_ACCESS 1
#define EXC_INST_ILLEGAL 2
#define EXC_BREAKPOINT 3
#define EXC_LOAD_MISALIGNED 4
#define EXC_LOAD_ACCESS 5
#define EXC_STORE_MISALIGNED 6
#define EXC_STORE_ACCESS 7
#define EXC_SYSCALL 8
#define EXC_HYPERVISOR_SYSCALL 9

View File

@ -183,6 +183,8 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
run->exit_reason = KVM_EXIT_UNKNOWN;
switch (trap->scause) {
case EXC_INST_ILLEGAL:
case EXC_LOAD_MISALIGNED:
case EXC_STORE_MISALIGNED:
if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) {
kvm_riscv_vcpu_trap_redirect(vcpu, trap);
ret = 1;