blob: fe3bb234cca331361d67b7a4006d5dc66e43e83c [file] [log] [blame]
From ed2e802688fb520cb64649d8022eb083bcd612c7 Mon Sep 17 00:00:00 2001
From: Huacai Chen <chenhc@lemote.com>
Date: Wed, 25 Mar 2020 11:44:54 +0800
Subject: [PATCH] MIPS/tlbex: Fix LDDIR usage in setup_pw() for Loongson-3
commit d191aaffe3687d1e73e644c185f5f0550ec242b5 upstream.
LDDIR/LDPTE is Loongson-3's acceleration for Page Table Walking. If BD
(Base Directory, the 4th page directory) is not enabled, then GDOffset
is biased by BadVAddr[63:62]. So, if GDOffset (aka. BadVAddr[47:36] for
Loongson-3) is big enough, "0b11(BadVAddr[63:62])|BadVAddr[47:36]|...."
can far beyond pg_swapper_dir. This means the pg_swapper_dir may NOT be
accessed by LDDIR correctly, so fix it by set PWDirExt in CP0_PWCtl.
Cc: <stable@vger.kernel.org>
Signed-off-by: Pei Huang <huangpei@loongson.cn>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index b0f70006bd85..7c8282399bf1 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -1482,6 +1482,7 @@ static void build_r4000_tlb_refill_handler(void)
static void setup_pw(void)
{
+ unsigned int pwctl;
unsigned long pgd_i, pgd_w;
#ifndef __PAGETABLE_PMD_FOLDED
unsigned long pmd_i, pmd_w;
@@ -1508,6 +1509,7 @@ static void setup_pw(void)
pte_i = ilog2(_PAGE_GLOBAL);
pte_w = 0;
+ pwctl = 1 << 30; /* Set PWDirExt */
#ifndef __PAGETABLE_PMD_FOLDED
write_c0_pwfield(pgd_i << 24 | pmd_i << 12 | pt_i << 6 | pte_i);
@@ -1518,8 +1520,9 @@ static void setup_pw(void)
#endif
#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
- write_c0_pwctl(1 << 6 | psn);
+ pwctl |= (1 << 6 | psn);
#endif
+ write_c0_pwctl(pwctl);
write_c0_kpgd((long)swapper_pg_dir);
kscratch_used_mask |= (1 << 7); /* KScratch6 is used for KPGD */
}
--
2.7.4