Re: [PATCH v4 06/25] reboot: Warn if unregister_restart_handler() fails
From: "Rafael J. Wysocki" <rafael@kernel.org>
Date: 2021-12-10 18:32:42
Also in:
linux-acpi, linux-m68k, linux-mips, linux-pm, linux-riscv, linux-sh, linux-tegra, lkml, xen-devel
On Fri, Nov 26, 2021 at 7:02 PM Dmitry Osipenko [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Emit warning if unregister_restart_handler() fails since it never should fail. This will ease further API development by catching mistakes early. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- kernel/reboot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/kernel/reboot.c b/kernel/reboot.c index e6659ae329f1..f0e7b9c13f6b 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c@@ -210,7 +210,7 @@ EXPORT_SYMBOL(register_restart_handler); */ int unregister_restart_handler(struct notifier_block *nb) { - return atomic_notifier_chain_unregister(&restart_handler_list, nb); + return WARN_ON(atomic_notifier_chain_unregister(&restart_handler_list, nb));
The only reason why it can fail is if the object pointed to by nb is not in the chain. Why WARN() about this? And what about systems with panic_on_warn set?
} EXPORT_SYMBOL(unregister_restart_handler); -- 2.33.1