[Qemu-devel] [PATCH 08/43] windbg: hook to wrmsr operation

[Mihail Abakumov]

Inserted hook to wrmsr operation. Windows Kernel put address on KPCR struct to 
fs/gs (x32/x64) register. Needs catch this moment and allow windbg server 
handle packets.

Signed-off-by: Mihail Abakumov <mikhail.abaku...@ispras.ru>
Signed-off-by: Pavel Dovgalyuk <dovga...@ispras.ru>
Signed-off-by: Dmitriy Koltunov <koltu...@ispras.ru>
---
 include/exec/windbgstub-utils.h |    3 +++
 include/exec/windbgstub.h       |    1 +
 target/i386/misc_helper.c       |    3 +++
 windbgstub-utils.c              |    8 ++++++++
 windbgstub.c                    |    8 ++++++++
 5 files changed, 23 insertions(+)

diff --git a/include/exec/windbgstub-utils.h b/include/exec/windbgstub-utils.h
index 65f336e4bf..90fb766839 100755
--- a/include/exec/windbgstub-utils.h
+++ b/include/exec/windbgstub-utils.h
@@ -62,4 +62,7 @@
     _t;                                                       \
 })
 
+bool windbg_on_load(void);
+void windbg_on_exit(void);
+
 #endif
diff --git a/include/exec/windbgstub.h b/include/exec/windbgstub.h
index 703fc26b8f..2dbf1b1f13 100755
--- a/include/exec/windbgstub.h
+++ b/include/exec/windbgstub.h
@@ -15,6 +15,7 @@
 #define WINDBG "windbg"
 #define WINDBG_DEBUG_ON false
 
+void windbg_try_load(void);
 int windbg_server_start(const char *device);
 
 #endif
diff --git a/target/i386/misc_helper.c b/target/i386/misc_helper.c
index 628f64aad5..ec1fcd2899 100644
--- a/target/i386/misc_helper.c
+++ b/target/i386/misc_helper.c
@@ -24,6 +24,7 @@
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
 #include "exec/address-spaces.h"
+#include "exec/windbgstub.h"
 
 void helper_outb(CPUX86State *env, uint32_t port, uint32_t data)
 {
@@ -385,6 +386,8 @@ void helper_wrmsr(CPUX86State *env)
         /* XXX: exception? */
         break;
     }
+
+    windbg_try_load();
 }
 
 void helper_rdmsr(CPUX86State *env)
diff --git a/windbgstub-utils.c b/windbgstub-utils.c
index dc5e505c63..b5fb6db3f2 100755
--- a/windbgstub-utils.c
+++ b/windbgstub-utils.c
@@ -10,3 +10,11 @@
  */
 
 #include "exec/windbgstub-utils.h"
+
+bool windbg_on_load(void)
+{
+    return false;
+}
+
+void windbg_on_exit(void)
+{}
diff --git a/windbgstub.c b/windbgstub.c
index 378d1b911f..99c3ef9b14 100755
--- a/windbgstub.c
+++ b/windbgstub.c
@@ -39,8 +39,16 @@ static void windbg_chr_receive(void *opaque, const uint8_t 
*buf, int size)
     }
 }
 
+void windbg_try_load(void)
+{
+    if (windbg_state && !windbg_state->is_loaded) {
+        windbg_state->is_loaded = windbg_on_load();
+    }
+}
+
 static void windbg_exit(void)
 {
+    windbg_on_exit();
     g_free(windbg_state);
 }