diff options
Diffstat (limited to 'arch/arm64/kernel/smp.c')
| -rw-r--r-- | arch/arm64/kernel/smp.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index f0a141dd565..c3cb160edc6 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -228,6 +228,19 @@ int __cpu_disable(void) return 0; } +static int op_cpu_kill(unsigned int cpu) +{ + /* + * If we have no means of synchronising with the dying CPU, then assume + * that it is really dead. We can only wait for an arbitrary length of + * time and hope that it's dead, so let's skip the wait and just hope. + */ + if (!cpu_ops[cpu]->cpu_kill) + return 1; + + return cpu_ops[cpu]->cpu_kill(cpu); +} + static DECLARE_COMPLETION(cpu_died); /* @@ -241,6 +254,15 @@ void __cpu_die(unsigned int cpu) return; } pr_notice("CPU%u: shutdown\n", cpu); + + /* + * Now that the dying CPU is beyond the point of no return w.r.t. + * in-kernel synchronisation, try to get the firwmare to help us to + * verify that it has really left the kernel before we consider + * clobbering anything it might still be using. + */ + if (!op_cpu_kill(cpu)) + pr_warn("CPU%d may not have shut down cleanly\n", cpu); } /* |