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@xxxxxxxxxxxxxxx>
Signed-off-by: Pei Huang <huangpei@xxxxxxxxxxx>
Signed-off-by: Huacai Chen <chenhc@xxxxxxxxxx>
---
arch/mips/mm/tlbex.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 344e6e9..da407cd 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -1480,6 +1480,7 @@ 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;
@@ -1506,6 +1507,7 @@ 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);
@@ -1516,8 +1518,9 @@ 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 */
}
--
2.7.0
