From: Palmer Dabbelt <palmer@sifive.com>
Date: Tue, 2 Oct 2018 19:14:57 +0000 (-0700)
Subject: RISC-V: Comment on the TLB flush in smp_callin()
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=b18d6f05252d6b3f725c08d8831a46b003df5b6b;p=openwrt%2Fstaging%2Fblogic.git

RISC-V: Comment on the TLB flush in smp_callin()

This isn't readily apparent from reading the code.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
[Atish: code comment formatting update]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
---

diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 56abab6a9812..712e9ca85904 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -106,6 +106,10 @@ asmlinkage void __init smp_callin(void)
 	trap_init();
 	notify_cpu_starting(smp_processor_id());
 	set_cpu_online(smp_processor_id(), 1);
+	/*
+	 * Remote TLB flushes are ignored while the CPU is offline, so emit
+	 * a local TLB flush right now just in case.
+	 */
 	local_flush_tlb_all();
 	local_irq_enable();
 	preempt_disable();