[ Upstream commit 82c08c3e7f ]
In case panic() and panic() called at the same time on different CPUS.
For example:
CPU 0:
panic()
__crash_kexec
machine_crash_shutdown
crash_smp_send_stop
machine_kexec
BUG_ON(num_online_cpus() > 1);
CPU 1:
panic()
local_irq_disable
panic_smp_self_stop
If CPU 1 calls panic_smp_self_stop() before crash_smp_send_stop(), kdump
fails. CPU1 can't receive the ipi irq, CPU1 will be always online.
To fix this problem, this patch split out the panic_smp_self_stop()
and add set_cpu_online(smp_processor_id(), false).
Signed-off-by: Yufen Wang <wangyufen@huawei.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
c871547ec2