sd-boot,sd-stub: also print version after the address

The kernel, systemd, and many other things print their version during boot.
sd-boot and sd-stub are also important, so let's print the version if EFI_DEBUG.
(If !EFI_DEBUG, continue to be quiet.)

When updating the docs, I saw that that the text in HACKING.md was out of date.
Instead of trying to update the instructions there, make it shorter and refer
the reader to tools/debug-sd-boot.sh for details.

2 files changed, 14 insertions, 12 deletions

diff --git a/src/boot/efi/util.c b/src/boot/efi/util.c
index b339021fe9..c5f1742466 100644
--- a/src/boot/efi/util.c
+++ b/src/boot/efi/util.c
@@ -4,6 +4,7 @@
 #include "proto/simple-text-io.h"
 #include "ticks.h"
 #include "util.h"
+#include "version.h"
 
 EFI_STATUS parse_boolean(const char *v, bool *b) {
         assert(b);
@@ -543,10 +544,9 @@ uint64_t get_os_indications_supported(void) {
         return osind;
 }
 
-#ifdef EFI_DEBUG
-extern uint8_t __ImageBase;
 __attribute__((noinline)) void notify_debugger(const char *identity, volatile bool wait) {
-        printf("%s@%p\n", identity, &__ImageBase);
+#ifdef EFI_DEBUG
+        printf("%s@%p %s\n", identity, &__ImageBase, GIT_VERSION);
         if (wait)
                 printf("Waiting for debugger to attach...\n");
 
@@ -554,15 +554,15 @@ __attribute__((noinline)) void notify_debugger(const char *identity, volatile bo
          * has attached to us. Just "set variable wait = 0" or "return" to continue. */
         while (wait)
                 /* Prefer asm based stalling so that gdb has a source location to present. */
-#if defined(__i386__) || defined(__x86_64__)
+#  if defined(__i386__) || defined(__x86_64__)
                 asm volatile("pause");
-#elif defined(__aarch64__)
+#  elif defined(__aarch64__)
                 asm volatile("wfi");
-#else
+#  else
                 BS->Stall(5000);
+#  endif
 #endif
 }
-#endif
 
 #ifdef EFI_DEBUG
 void hexdump(const char16_t *prefix, const void *data, size_t size) {
diff --git a/src/boot/efi/util.h b/src/boot/efi/util.h
index bb917faf55..929f3bca8c 100644
--- a/src/boot/efi/util.h
+++ b/src/boot/efi/util.h
@@ -6,6 +6,9 @@
 #include "proto/file-io.h"
 #include "string-util-fundamental.h"
 
+/* This is provided by linker script. */
+extern uint8_t __ImageBase;
+
 static inline void free(void *p) {
         if (!p)
                 return;
@@ -160,13 +163,12 @@ static inline void *PHYSICAL_ADDRESS_TO_POINTER(EFI_PHYSICAL_ADDRESS addr) {
 
 uint64_t get_os_indications_supported(void);
 
-#ifdef EFI_DEBUG
-/* Report the relocated position of text and data sections so that a debugger
- * can attach to us. See debug-sd-boot.sh for how this can be done. */
+/* If EFI_DEBUG, print our name and version and also report the address of the image base so a debugger can
+ * be attached. See debug-sd-boot.sh for how this can be done. */
 void notify_debugger(const char *identity, bool wait);
+
+#ifdef EFI_DEBUG
 void hexdump(const char16_t *prefix, const void *data, size_t size);
-#else
-#  define notify_debugger(i, w)
 #endif
 
 /* On x86 the compiler assumes a different incoming stack alignment than what we get.