From: Huacai Chen <chenhuacai@loongson.cn>
Date: Wed, 12 Oct 2022 08:36:08 +0000 (+0800)
Subject: LoongArch: Flush TLB earlier at initialization
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1299a129a9f927433ba792b242c1f287a96059e7;p=linux.git

LoongArch: Flush TLB earlier at initialization

Move local_flush_tlb_all() earlier (just after setup_ptwalker() and
before page allocation). This can avoid stale TLB entries misguiding
the later page allocation. Without this patch the second kernel of
kexec/kdump fails to boot SMP.

BTW, move output_pgtable_bits_defines() into tlb_init() since it has
nothing to do with tlb handler setup.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---

diff --git a/arch/loongarch/mm/tlb.c b/arch/loongarch/mm/tlb.c
index 9818ce11546bc..da3681f131c8d 100644
--- a/arch/loongarch/mm/tlb.c
+++ b/arch/loongarch/mm/tlb.c
@@ -258,7 +258,7 @@ extern long exception_handlers[VECSIZE * 128 / sizeof(long)];
 void setup_tlb_handler(int cpu)
 {
 	setup_ptwalker();
-	output_pgtable_bits_defines();
+	local_flush_tlb_all();
 
 	/* The tlb handlers are generated only once */
 	if (cpu == 0) {
@@ -301,6 +301,7 @@ void tlb_init(int cpu)
 	write_csr_pagesize(PS_DEFAULT_SIZE);
 	write_csr_stlbpgsize(PS_DEFAULT_SIZE);
 	write_csr_tlbrefill_pagesize(PS_DEFAULT_SIZE);
+
 	setup_tlb_handler(cpu);
-	local_flush_tlb_all();
+	output_pgtable_bits_defines();
 }