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

From: Kees Cook
Date: Fri May 15 2020 - 14:45:04 EST


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@xxxxxxxxxxxxxx/

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
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