From: Will Deacon <will@kernel.org>
Date: Fri, 23 Aug 2019 13:03:55 +0100
Subject: arm64: mm: Add ISB instruction to set_pgd()

Git-commit: eb6a4dcce33925ac95023bbe5199474f8db40ba7
Patch-mainline: v5.4-rc1
References: jsc#13705,jsc#13695

Commit 6a4cbd63c25a ("Revert "arm64: Remove unnecessary ISBs from
set_{pte,pmd,pud}"") reintroduced ISB instructions to some of our
page table setter functions in light of a recent clarification to the
Armv8 architecture. Although 'set_pgd()' isn't currently used to update
a live page table, add the ISB instruction there too for consistency
with the other macros and to provide some future-proofing if we use it
on live tables in the future.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 arch/arm64/include/asm/pgtable.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index feda7294320c..2faa77635942 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -605,6 +605,7 @@ static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 
 	WRITE_ONCE(*pgdp, pgd);
 	dsb(ishst);
+	isb();
 }
 
 static inline void pgd_clear(pgd_t *pgdp)
-- 
2.26.2