4.9-stable review patch. If anyone has any objections, please let me know.
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From: Arnd Bergmann arnd@arndb.de
commit 12f043ff2b28fa64c9123b454cbe30a8a9e1967e upstream.
With 4 levels of 16KB pages, we get this warning about the fact that we are copying a whole page into an array that is declared as having only two pointers for the top level of the page table:
arch/arm64/mm/mmu.c: In function 'paging_init': arch/arm64/mm/mmu.c:528:2: error: 'memcpy' writing 16384 bytes into a region of size 16 overflows the destination [-Werror=stringop-overflow=]
This is harmless since we actually reserve a whole page in the definition of the array that comes from, and just the extern declaration is short. The pgdir is initialized to zero either way, so copying the actual entries here seems like the best solution.
Acked-by: Ard Biesheuvel ard.biesheuvel@linaro.org Acked-by: Mark Rutland mark.rutland@arm.com Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Will Deacon will.deacon@arm.com [slightly adapted to apply on 4.9] Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/mm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -479,7 +479,7 @@ void __init paging_init(void) * To do this we need to go via a temporary pgd. */ cpu_replace_ttbr1(__va(pgd_phys)); - memcpy(swapper_pg_dir, pgd, PAGE_SIZE); + memcpy(swapper_pg_dir, pgd, PGD_SIZE); cpu_replace_ttbr1(swapper_pg_dir);
pgd_clear_fixmap();