[PATCH AUTOSEL 4.9 14/21] MIPS: kexec: Mark CPU offline before disabling local IRQ

[Sasha Levin]

From: Dengcheng Zhu <dzhu@xxxxxxxxxxxx>

[ Upstream commit dc57aaf95a516f70e2d527d8287a0332c481a226 ]

After changing CPU online status, it will not be sent any IPIs such as in
__flush_cache_all() on software coherency systems. Do this before disabling
local IRQ.

Signed-off-by: Dengcheng Zhu <dzhu@xxxxxxxxxxxx>
Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Patchwork: https://patchwork.linux-mips.org/patch/20571/
Cc: pburton@xxxxxxxxxxxx
Cc: ralf@xxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: rachel.mozes@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/mips/kernel/crash.c         | 3 +++
 arch/mips/kernel/machine_kexec.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/arch/mips/kernel/crash.c b/arch/mips/kernel/crash.c
index 1723b1762297..e757f36cea6f 100644
--- a/arch/mips/kernel/crash.c
+++ b/arch/mips/kernel/crash.c
@@ -34,6 +34,9 @@ static void crash_shutdown_secondary(void *passed_regs)
 	if (!cpu_online(cpu))
 		return;
 
+	/* We won't be sent IPIs any more. */
+	set_cpu_online(cpu, false);
+
 	local_irq_disable();
 	if (!cpumask_test_cpu(cpu, &cpus_in_crash))
 		crash_save_cpu(regs, cpu);
diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c
index 59725204105c..32b567e88b02 100644
--- a/arch/mips/kernel/machine_kexec.c
+++ b/arch/mips/kernel/machine_kexec.c
@@ -96,6 +96,9 @@ machine_kexec(struct kimage *image)
 			*ptr = (unsigned long) phys_to_virt(*ptr);
 	}
 
+	/* Mark offline BEFORE disabling local irq. */
+	set_cpu_online(smp_processor_id(), false);
+
 	/*
 	 * we do not want to be bothered.
 	 */
-- 
2.17.1