Patchwork [06/31] openpic: don't crash on a register access without a CPU context

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Submitter Alexander Graf
Date Jan. 7, 2013, 3:38 p.m.
Message ID <1357573140-8877-7-git-send-email-agraf@suse.de>
Download mbox | patch
Permalink /patch/209976/
State New
Headers show

Comments

Alexander Graf - Jan. 7, 2013, 3:38 p.m.
From: Scott Wood <scottwood@freescale.com>

If we access a register via the QEMU memory inspection commands (e.g.
"xp") rather than from guest code, we won't have a CPU context.
Gracefully fail to access the register in that case, rather than
crashing.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
 hw/openpic.c |   16 +++++++++++++++-
 1 files changed, 15 insertions(+), 1 deletions(-)

Patch

diff --git a/hw/openpic.c b/hw/openpic.c
index 10dbdf7..93e8208 100644
--- a/hw/openpic.c
+++ b/hw/openpic.c
@@ -161,7 +161,11 @@  static inline int test_bit(uint32_t *field, int bit)
 
 static int get_current_cpu(void)
 {
-  return cpu_single_env->cpu_index;
+    if (!cpu_single_env) {
+        return -1;
+    }
+
+    return cpu_single_env->cpu_index;
 }
 
 static uint32_t openpic_cpu_read_internal(void *opaque, hwaddr addr,
@@ -810,6 +814,11 @@  static void openpic_cpu_write_internal(void *opaque, hwaddr addr,
 
     DPRINTF("%s: cpu %d addr " TARGET_FMT_plx " <= %08x\n", __func__, idx,
             addr, val);
+
+    if (idx < 0) {
+        return;
+    }
+
     if (addr & 0xF)
         return;
     dst = &opp->dst[idx];
@@ -875,6 +884,11 @@  static uint32_t openpic_cpu_read_internal(void *opaque, hwaddr addr,
 
     DPRINTF("%s: cpu %d addr " TARGET_FMT_plx "\n", __func__, idx, addr);
     retval = 0xFFFFFFFF;
+
+    if (idx < 0) {
+        return retval;
+    }
+
     if (addr & 0xF)
         return retval;
     dst = &opp->dst[idx];