From: Ralf Baechle <ralf@linux-mips.org>
Date: Tue, 16 Oct 2012 23:01:21 +0000 (+0200)
Subject: MIPS: hugetlbfs: Fix hazard between tlb write and pagemask restoration.
X-Git-Tag: firefly_0821_release~3680^2~1781^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fb944c9ba3f4838a64929a1926822e987b4e44c0;p=firefly-linux-kernel-4.4.55.git

MIPS: hugetlbfs: Fix hazard between tlb write and pagemask restoration.

On some CPU the write to pagemask might complete before the TLB write
instruction reads from the pagemask register.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---

diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
index 87b9cfcc30ff..4b9b935a070e 100644
--- a/arch/mips/mm/tlb-r4k.c
+++ b/arch/mips/mm/tlb-r4k.c
@@ -320,6 +320,7 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte)
 			tlb_write_random();
 		else
 			tlb_write_indexed();
+		tlbw_use_hazard();
 		write_c0_pagemask(PM_DEFAULT_MASK);
 	} else
 #endif