linux-user: Add guest memory layout to exception dump

When the emulation stops with a hard exception it's very useful for
debugging purposes to dump the current guest memory layout (for an
example see /proc/self/maps) beside the CPU registers.

The open_self_maps() function provides such a memory dump, but since
it's located in the syscall.c file, various changes (add #includes, make
this function externally visible, ...) are needed to be able to call it
from the existing EXCP_DUMP() macro.

This patch takes another approach by re-defining EXCP_DUMP() to call
target_exception_dump(), which is in syscall.c, consolidates the log
print functions and allows to add the call to dump the memory layout.

Beside a reduced code footprint, this approach keeps the changes across
the various callers minimal, and keeps EXCP_DUMP() highlighted as
important macro/function.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <Y1bzAWbw07WBKPxw@p100>
[lv: remove pc declaration and setting]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

1 files changed, 28 insertions, 0 deletions

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index e985ad167f..8402c1399d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -183,6 +183,7 @@ struct file_clone_range {
 #include "qapi/error.h"
 #include "fd-trans.h"
 #include "tcg/tcg.h"
+#include "cpu_loop-common.h"
 
 #ifndef CLONE_IO
 #define CLONE_IO                0x80000000      /* Clone io context */
@@ -8169,6 +8170,33 @@ static int is_proc_myself(const char *filename, const char *entry)
     return 0;
 }
 
+static void excp_dump_file(FILE *logfile, CPUArchState *env,
+                      const char *fmt, int code)
+{
+    if (logfile) {
+        CPUState *cs = env_cpu(env);
+
+        fprintf(logfile, fmt, code);
+        fprintf(logfile, "Failing executable: %s\n", exec_path);
+        cpu_dump_state(cs, logfile, 0);
+        open_self_maps(env, fileno(logfile));
+    }
+}
+
+void target_exception_dump(CPUArchState *env, const char *fmt, int code)
+{
+    /* dump to console */
+    excp_dump_file(stderr, env, fmt, code);
+
+    /* dump to log file */
+    if (qemu_log_separate()) {
+        FILE *logfile = qemu_log_trylock();
+
+        excp_dump_file(logfile, env, fmt, code);
+        qemu_log_unlock(logfile);
+    }
+}
+
 #if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN || \
     defined(TARGET_SPARC) || defined(TARGET_M68K) || defined(TARGET_HPPA)
 static int is_proc(const char *filename, const char *entry)