[RESEND PATCH 2/2] RISC-V: KVM: Propagate interrupted G-stage faults

[Xie Bo]

__kvm_faultin_pfn() reports an interrupted host page fault with
KVM_PFN_ERR_SIGPENDING. RISC-V currently handles it as a generic error PFN
and returns -EFAULT.

Return -EINTR for the signal-pending sentinel so callers can distinguish
an interrupted fault from an invalid userspace mapping. Do not log the
expected interruption as a vCPU exit error.

Fixes: 9d05c1fee837 ("RISC-V: KVM: Implement stage2 page table programming")
Cc: stable at vger.kernel.org
Signed-off-by: Xie Bo <xb at ultrarisc.com>
---
 arch/riscv/kvm/mmu.c       | 2 ++
 arch/riscv/kvm/vcpu_exit.c | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index d189fd5..3e955d8 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -708,6 +708,8 @@ int kvm_riscv_mmu_map(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
 				vma_pageshift, current);
 		return 0;
 	}
+	if (is_sigpending_pfn(hfn))
+		return -EINTR;
 	if (is_error_noslot_pfn(hfn))
 		return -EFAULT;
 
diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
index 88e0c36..8d36eb8 100644
--- a/arch/riscv/kvm/vcpu_exit.c
+++ b/arch/riscv/kvm/vcpu_exit.c
@@ -283,7 +283,7 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
 	}
 
 	/* Print details in-case of error */
-	if (ret < 0) {
+	if (ret < 0 && ret != -EINTR) {
 		kvm_err("VCPU exit error %d\n", ret);
 		kvm_err("SEPC=0x%lx SSTATUS=0x%lx HSTATUS=0x%lx\n",
 			vcpu->arch.guest_context.sepc,