Commit d691a3cf authored Mar 17, 2017 by Kirill A. Shutemov Committed by Ingo Molnar Mar 27, 2017

x86/kasan: Prepare clear_pgds() to switch to <asm-generic/pgtable-nop4d.h>

With folded p4d, pgd_clear() is a nop. Change clear_pgds() to use
p4d_clear() instead.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170317185515.8636-5-kirill.shutemov@linux.intel.com

Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 45478336

arch/x86/mm/kasan_init_64.c

+13 −2

Original line number	Diff line number	Diff line
		@@ -32,8 +32,19 @@ static int __init map_range(struct range *range)
		static void __init clear_pgds(unsigned long start,
		unsigned long end)
		{
		for (; start < end; start += PGDIR_SIZE)
		pgd_clear(pgd_offset_k(start));
		pgd_t *pgd;

		for (; start < end; start += PGDIR_SIZE) {
		pgd = pgd_offset_k(start);
		/*
		* With folded p4d, pgd_clear() is nop, use p4d_clear()
		* instead.
		*/
		if (CONFIG_PGTABLE_LEVELS < 5)
		p4d_clear(p4d_offset(pgd, start));
		else
		pgd_clear(pgd);
		}
		}

		static void __init kasan_map_early_shadow(pgd_t *pgd)