[Skiboot] [PATCH] core/fast-reboot: disable fast-reboot when firmware secureboot is enabled

[Eric Richter]

The possible impact of the current fast-reboot design on secure/trusted
boot is unclear, and will likely need additional review and testing.
While fast-reboot is disabled by default, it can be enabled by two
nvram parameters -- one of which circumvents the built-in
disable_fast_reboot() mechanism.

This patch prevents all calls to fast_reboot() when firmware secure boot
is enabled.

Signed-off-by: Eric Richter <erichte at linux.ibm.com>
---
 core/fast-reboot.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/core/fast-reboot.c b/core/fast-reboot.c
index 02f0ca05..c4361bb1 100644
--- a/core/fast-reboot.c
+++ b/core/fast-reboot.c
@@ -23,6 +23,8 @@
 #include <ipmi.h>
 #include <direct-controls.h>
 #include <nvram.h>
+#include <types.h>
+#include <secureboot.h>
 
 /* Flag tested by the OPAL entry code */
 static volatile bool fast_boot_release;
@@ -109,6 +111,12 @@ void fast_reboot(void)
 		return;
 	}
 
+	if (is_fw_secureboot()) {
+		prlog(PR_DEBUG,
+		      "RESET: Fast reboot disabled by FW secureboot\n");
+		return;
+	}
+
 	/*
 	 * Ensure all other CPUs have left OPAL calls.
 	 */
-- 
2.21.1