summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/smp.c
diff options
context:
space:
mode:
authorYufen Wang <wangyufen@huawei.com>2018-11-02 11:51:31 +0100
committerRussell King <rmk+kernel@armlinux.org.uk>2018-11-08 10:57:11 +0000
commit82c08c3e7f171aa7f579b231d0abbc1d62e91974 (patch)
treec588d6dbdde32083f8d1c42743cf0d9b43944fd4 /arch/arm/kernel/smp.c
parente2b85f709a705808a71560de60732fd49e4516a5 (diff)
downloadlinux-82c08c3e7f171aa7f579b231d0abbc1d62e91974.tar.bz2
ARM: 8808/1: kexec:offline panic_smp_self_stop CPU
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>
Diffstat (limited to 'arch/arm/kernel/smp.c')
-rw-r--r--arch/arm/kernel/smp.c15
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 0978282d5fc2..f574a5e0d589 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -693,6 +693,21 @@ void smp_send_stop(void)
pr_warn("SMP: failed to stop secondary CPUs\n");
}
+/* In case panic() and panic() called at the same time on CPU1 and CPU2,
+ * and CPU 1 calls panic_smp_self_stop() before crash_smp_send_stop()
+ * CPU1 can't receive the ipi irqs from CPU2, CPU1 will be always online,
+ * kdump fails. So split out the panic_smp_self_stop() and add
+ * set_cpu_online(smp_processor_id(), false).
+ */
+void panic_smp_self_stop(void)
+{
+ pr_debug("CPU %u will stop doing anything useful since another CPU has paniced\n",
+ smp_processor_id());
+ set_cpu_online(smp_processor_id(), false);
+ while (1)
+ cpu_relax();
+}
+
/*
* not supported here
*/