[PATCH] [PATCH] arm64: Boot failure on m400 with new cont PTEs

[Jeremy Linton]

The HP m400 fails to boot the linux 4.4rc1 kernel. It usually
hangs or sometimes takes an unhanded exception around the DMA
zone messages. This was bisected to the new CONT PTE changes.

Adding an extra flush_tlb_all() in the code path which is
changing the kernel permissions allows the machine to boot
consistently.

Signed-off-by: Jeremy Linton <jeremy.linton at arm.com>
---
 arch/arm64/mm/mmu.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index e3f563c..e92fe77 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -121,6 +121,7 @@ static void __populate_init_pte(pte_t *pte, unsigned long addr,
 		pfn++;
 		addr += PAGE_SIZE;
 	} while (addr != end);
+	flush_tlb_all();
 }
 
 static void alloc_init_pte(pmd_t *pmd, unsigned long addr,
-- 
2.4.3