[PATCH v4 1/6] printk: Collapse shutdown types into a single dump reason

[Kees Cook]

To turn the KMSG_DUMP_* reasons into a more ordered list, collapse
the redundant KMSG_DUMP_(RESTART|HALT|POWEROFF) reasons into
KMSG_DUMP_SHUTDOWN. The current users already don't meaningfully
distinguish between them, so there's no need to, as discussed here:
https://lore.kernel.org/lkml/CA+CK2bAPv5u1ih5y9t5FUnTyximtFCtDYXJCpuyjOyHNOkRdqw@mail.gmail.com/

Signed-off-by: Kees Cook <keescook at chromium.org>
---
 arch/powerpc/kernel/nvram_64.c | 4 +---
 fs/pstore/platform.c           | 8 ++------
 include/linux/kmsg_dump.h      | 4 +---
 kernel/reboot.c                | 6 +++---
 4 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index fb4f61096613..0cd1c88bfc8b 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -655,9 +655,7 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
 	int rc = -1;
 
 	switch (reason) {
-	case KMSG_DUMP_RESTART:
-	case KMSG_DUMP_HALT:
-	case KMSG_DUMP_POWEROFF:
+	case KMSG_DUMP_SHUTDOWN:
 		/* These are almost always orderly shutdowns. */
 		return;
 	case KMSG_DUMP_OOPS:
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 072440457c08..90d74ebaa70a 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -144,12 +144,8 @@ static const char *get_reason_str(enum kmsg_dump_reason reason)
 		return "Oops";
 	case KMSG_DUMP_EMERG:
 		return "Emergency";
-	case KMSG_DUMP_RESTART:
-		return "Restart";
-	case KMSG_DUMP_HALT:
-		return "Halt";
-	case KMSG_DUMP_POWEROFF:
-		return "Poweroff";
+	case KMSG_DUMP_SHUTDOWN:
+		return "Shutdown";
 	default:
 		return "Unknown";
 	}
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index 2e7a1e032c71..3f82b5cb2d82 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -25,9 +25,7 @@ enum kmsg_dump_reason {
 	KMSG_DUMP_PANIC,
 	KMSG_DUMP_OOPS,
 	KMSG_DUMP_EMERG,
-	KMSG_DUMP_RESTART,
-	KMSG_DUMP_HALT,
-	KMSG_DUMP_POWEROFF,
+	KMSG_DUMP_SHUTDOWN,
 };
 
 /**
diff --git a/kernel/reboot.c b/kernel/reboot.c
index c4d472b7f1b4..491f1347bf43 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -250,7 +250,7 @@ void kernel_restart(char *cmd)
 		pr_emerg("Restarting system\n");
 	else
 		pr_emerg("Restarting system with command '%s'\n", cmd);
-	kmsg_dump(KMSG_DUMP_RESTART);
+	kmsg_dump(KMSG_DUMP_SHUTDOWN);
 	machine_restart(cmd);
 }
 EXPORT_SYMBOL_GPL(kernel_restart);
@@ -274,7 +274,7 @@ void kernel_halt(void)
 	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	pr_emerg("System halted\n");
-	kmsg_dump(KMSG_DUMP_HALT);
+	kmsg_dump(KMSG_DUMP_SHUTDOWN);
 	machine_halt();
 }
 EXPORT_SYMBOL_GPL(kernel_halt);
@@ -292,7 +292,7 @@ void kernel_power_off(void)
 	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	pr_emerg("Power down\n");
-	kmsg_dump(KMSG_DUMP_POWEROFF);
+	kmsg_dump(KMSG_DUMP_SHUTDOWN);
 	machine_power_off();
 }
 EXPORT_SYMBOL_GPL(kernel_power_off);
-- 
2.20.1