On 2026/3/5 下午9:54, Andrew S. Rightenburg via qemu development wrote:
From: rail5 <[email protected]>

loongarch_cpu_do_interrupt() updates CSR_BADI by fetching the faulting
instruction with cpu_ldl_code_mmu().

For a PNX exception (instruction fetch prohibited by NX), fetching the
instruction at env->pc will fault with PNX again. This can lead to an
infinite exception loop.

Treat PNX like other instruction-fetch exceptions (PIF/ADEF) and do not
update CSR_BADI for it.

Fixes: 410dfbf620a ("target/loongarch: Move TCG specified functions to 
tcg_cpu.c")
Cc: [email protected]
Signed-off-by: rail5 (Andrew S. Rightenburg) <[email protected]>
---
  target/loongarch/tcg/tcg_cpu.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/loongarch/tcg/tcg_cpu.c b/target/loongarch/tcg/tcg_cpu.c
index af92277669..31d3db6e8e 100644
--- a/target/loongarch/tcg/tcg_cpu.c
+++ b/target/loongarch/tcg/tcg_cpu.c
@@ -109,6 +109,7 @@ static void loongarch_cpu_do_interrupt(CPUState *cs)
          }
          QEMU_FALLTHROUGH;
      case EXCCODE_PIF:
+    case EXCCODE_PNX:
      case EXCCODE_ADEF:
          cause = cs->exception_index;
          update_badinstr = 0;
@@ -129,7 +130,6 @@ static void loongarch_cpu_do_interrupt(CPUState *cs)
      case EXCCODE_PIS:
      case EXCCODE_PME:
      case EXCCODE_PNR:
-    case EXCCODE_PNX:
      case EXCCODE_PPI:
          cause = cs->exception_index;
          break;

Reviewed-by: Bibo Mao <[email protected]>


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