grub2/safe_tpm_pcr_snapshot.patch

---
 grub-core/commands/tpm.c |   46 ++++++++++++++++++++++++++++++++++++----------
 util/grub-install.c      |    6 ++++--
 2 files changed, 40 insertions(+), 12 deletions(-)

--- a/grub-core/commands/tpm.c
+++ b/grub-core/commands/tpm.c
@@ -27,8 +27,10 @@
 #include <grub/verify.h>
 #include <grub/dl.h>
 #include <grub/extcmd.h>
+#ifdef GRUB_MACHINE_EFI
 #include <grub/tpm2/tpm2.h>
 #include <grub/efi/efi.h>
+#endif
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -97,12 +99,6 @@
   .verify_string = grub_tpm_verify_string,
 };
 
-/*
- * Preserve current PCR values and record them to an EFI variable
- */
-#define GRUB2_PCR_BITMASK_DEFAULT	((1 << 16) - 1)
-#define GRUB2_PCR_BITMASK_ALL		((1 << 24) - 1)
-
 static const struct grub_arg_option grub_tpm_record_pcrs_options[] =
   {
     {
@@ -118,6 +114,14 @@
     {0, 0, 0, 0, 0, 0}
   };
 
+#ifdef GRUB_MACHINE_EFI
+
+/*
+ * Preserve current PCR values and record them to an EFI variable
+ */
+#define GRUB2_PCR_BITMASK_DEFAULT	((1 << 16) - 1)
+#define GRUB2_PCR_BITMASK_ALL		((1 << 24) - 1)
+
 static grub_err_t
 grub_tpm_parse_pcr_index (const char *word, const char **end_ret, unsigned int *index)
 {
@@ -269,6 +273,10 @@
   grub_size_t size = 0;
   int n, rv = 1;
 
+  /* To prevent error: unable to read PCR from TPM, if no TPM device available */
+  if (!grub_tpm_present())
+    return GRUB_ERR_NONE;
+
   if (argc == 0)
     pcr_bitmask = GRUB2_PCR_BITMASK_DEFAULT;
   else
@@ -297,6 +305,18 @@
   return rv;
 }
 
+#else
+
+static grub_err_t
+grub_tpm_record_pcrs (grub_extcmd_context_t ctxt __attribute__((unused)),
+    int argc __attribute__((unused)),
+    char **args __attribute__((unused)))
+{
+  return GRUB_ERR_NONE;
+}
+
+#endif
+
 static grub_extcmd_t cmd;
 
 GRUB_MOD_INIT (tpm)
--- a/util/grub-install.c
+++ b/util/grub-install.c
@@ -1560,8 +1560,9 @@
 
   grub_util_unlink (load_cfg);
 
-  if (1)
+  if (platform == GRUB_INSTALL_PLATFORM_X86_64_EFI && have_cryptodisk)
     {
+      grub_install_push_module ("tpm");
       load_cfg_f = grub_util_fopen (load_cfg, "wb");
       have_load_cfg = 1;
       fprintf (load_cfg_f, "tpm_record_pcrs 0-9\n");
@@ -1569,7 +1570,8 @@
 
   if (debug_image && debug_image[0])
     {
-      load_cfg_f = grub_util_fopen (load_cfg, "wb");
+      if (!load_cfg_f)
+	load_cfg_f = grub_util_fopen (load_cfg, "wb");
       have_load_cfg = 1;
       fprintf (load_cfg_f, "set debug='%s'\n",
               debug_image);