diff mbox series

[PULL,05/14] target/arm: Report M-profile alignment faults correctly to the guest

Message ID 20210727104801.29728-6-peter.maydell@linaro.org
State New
Headers show
Series [PULL,01/14] hw/arm/smmuv3: Check 31st bit to see if CD is valid | expand

Commit Message

Peter Maydell July 27, 2021, 10:47 a.m. UTC 
For M-profile, we weren't reporting alignment faults triggered by the
generic TCG code correctly to the guest.  These get passed into
arm_v7m_cpu_do_interrupt() as an EXCP_DATA_ABORT with an A-profile
style exception.fsr value of 1.  We didn't check for this, and so
they fell through into the default of "assume this is an MPU fault"
and were reported to the guest as a data access violation MPU fault.

Report these alignment faults as UsageFaults which set the UNALIGNED
bit in the UFSR.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210723162146.5167-4-peter.maydell@linaro.org
---
 target/arm/m_helper.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/target/arm/m_helper.c b/target/arm/m_helper.c
index f352346a964..20761c94877 100644
--- a/target/arm/m_helper.c
+++ b/target/arm/m_helper.c
@@ -2248,6 +2248,7 @@  void arm_v7m_cpu_do_interrupt(CPUState *cs)
         env->v7m.sfsr |= R_V7M_SFSR_LSERR_MASK;
         break;
     case EXCP_UNALIGNED:
+        /* Unaligned faults reported by M-profile aware code */
         armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE, env->v7m.secure);
         env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_UNALIGNED_MASK;
         break;
@@ -2320,6 +2321,13 @@  void arm_v7m_cpu_do_interrupt(CPUState *cs)
             }
             armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_BUS, false);
             break;
+        case 0x1: /* Alignment fault reported by generic code */
+            qemu_log_mask(CPU_LOG_INT,
+                          "...really UsageFault with UFSR.UNALIGNED\n");
+            env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_UNALIGNED_MASK;
+            armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE,
+                                    env->v7m.secure);
+            break;
         default:
             /*
              * All other FSR values are either MPU faults or "can't happen