[Qemu-devel] [PATCH 1/2] ROM write access for debugging

[Jan Kiszka <jan.kiszka@siemens.com>]

Enhance cpu_memory_rw_debug so that it can write even to ROM regions.
This allows to modify ROM via gdb (I see no point in denying this to the
user), and it will enable us to drop kvm_patch_opcode_byte().

Credits go to Avi for suggesting this.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

 exec.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/exec.c b/exec.c
index 86ab7de..5e94a8f 100644
--- a/exec.c
+++ b/exec.c
@@ -3448,7 +3448,7 @@ void stq_phys(target_phys_addr_t addr, uint64_t val)
 
 #endif
 
-/* virtual memory access for debug */
+/* virtual memory access for debug (includes writing to ROM) */
 int cpu_memory_rw_debug(CPUState *env, target_ulong addr,
                         uint8_t *buf, int len, int is_write)
 {
@@ -3465,8 +3465,13 @@ int cpu_memory_rw_debug(CPUState *env, target_ulong addr,
         l = (page + TARGET_PAGE_SIZE) - addr;
         if (l > len)
             l = len;
-        cpu_physical_memory_rw(phys_addr + (addr & ~TARGET_PAGE_MASK),
-                               buf, l, is_write);
+        phys_addr += (addr & ~TARGET_PAGE_MASK);
+#if !defined(CONFIG_USER_ONLY)
+        if (is_write)
+            cpu_physical_memory_write_rom(phys_addr, buf, l);
+        else
+#endif
+            cpu_physical_memory_rw(phys_addr, buf, l, is_write);
         len -= l;
         buf += l;
         addr += l;