4.4-stable review patch. If anyone has any objections, please let me know.
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From: Dengcheng Zhu dzhu@wavecomp.com
[ 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@wavecomp.com Signed-off-by: Paul Burton paul.burton@mips.com Patchwork: https://patchwork.linux-mips.org/patch/20571/ Cc: pburton@wavecomp.com Cc: ralf@linux-mips.org Cc: linux-mips@linux-mips.org Cc: rachel.mozes@intel.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/mips/kernel/crash.c | 3 +++ arch/mips/kernel/machine_kexec.c | 3 +++ 2 files changed, 6 insertions(+)
--- a/arch/mips/kernel/crash.c +++ b/arch/mips/kernel/crash.c @@ -34,6 +34,9 @@ static void crash_shutdown_secondary(voi 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); --- a/arch/mips/kernel/machine_kexec.c +++ b/arch/mips/kernel/machine_kexec.c @@ -95,6 +95,9 @@ 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. */