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From: Faiyaz Mohammed <quic_faiyazm@quicinc.com>
To: <benjamin.bara@skidata.com>, <dmitry.osipenko@collabora.com>,
        <lee@kernel.org>, <daniel.lezcano@linaro.org>, <ldmldm05@gmail.com>,
        <j.granados@samsung.com>, <quic_faiyazm@quicinc.com>,
        <linux-kernel@vger.kernel.org>
Subject: [PATCH] kernel/reboot: enhance dmesg logging for system restart
Date: Fri, 7 Jun 2024 16:29:06 +0530
Message-ID: <20240607105906.4192924-1-quic_faiyazm@quicinc.com>
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It is useful to add the PID and Comm information along with command info.

Currently, when system reboot kernel logs don not print PID and Comm:

reboot: Restarting system with command 'reboot,scheduled_reboot'
reboot: Restarting system with command 'RescueParty'
reboot: Restarting system with command 'bootloader'
reboot: Restarting system with command 'recovery'
reboot: Restarting system with command 'userrequested,recovery’

For Example after adding PID and Comm:

reboot: PID: 1 Comm: init Restarting system with command 'shell'
reboot: PID: 1 Comm: init Restarting system with command 'bootloader'

Signed-off-by: Faiyaz Mohammed <quic_faiyazm@quicinc.com>
---
 kernel/reboot.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/kernel/reboot.c b/kernel/reboot.c
index f05dbde2c93f..91a4a1428eb9 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -274,14 +274,17 @@ static void do_kernel_restart_prepare(void)
  */
 void kernel_restart(char *cmd)
 {
+	char comm[sizeof(current->comm)];
+
+	get_task_comm(comm, current);
 	kernel_restart_prepare(cmd);
 	do_kernel_restart_prepare();
 	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	if (!cmd)
-		pr_emerg("Restarting system\n");
+		pr_emerg("PID: %d Comm: %s Restarting system\n", current->pid, comm);
 	else
-		pr_emerg("Restarting system with command '%s'\n", cmd);
+		pr_emerg("PID: %d Comm: %s Restarting system with command '%s'\n", current->pid, comm, cmd);
 	kmsg_dump(KMSG_DUMP_SHUTDOWN);
 	machine_restart(cmd);
 }
-- 
2.25.1