From 5b0093f3a4acc7f393f102e7e064f70efc3375b9 Mon Sep 17 00:00:00 2001 From: Matt Redfearn Date: Fri, 4 Nov 2016 09:28:58 +0000 Subject: [PATCH] MIPS: SMP-CPS: Don't BUG if a CPU fails to start If there is no online CPU within a core which could receive the IPI to start another VP in that core, a BUG() is triggered. Instead print a warning and gracefully handle the failure such that the system remains usable, albeit without the requested secondary CPU. Signed-off-by: Matt Redfearn Cc: Masahiro Yamada Cc: James Hogan Cc: Paul Burton Cc: Qais Yousef Cc: Andrew Morton Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14504/ Signed-off-by: Ralf Baechle --- arch/mips/kernel/smp-cps.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c index 44339b470ef4..a2544c2394e4 100644 --- a/arch/mips/kernel/smp-cps.c +++ b/arch/mips/kernel/smp-cps.c @@ -326,7 +326,11 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle) if (cpu_online(remote)) break; } - BUG_ON(remote >= NR_CPUS); + if (remote >= NR_CPUS) { + pr_crit("No online CPU in core %u to start CPU%d\n", + core, cpu); + goto out; + } err = smp_call_function_single(remote, remote_vpe_boot, NULL, 1); -- 2.45.2