Commit cbe0317b authored Jun 06, 2017 by Kirill A. Shutemov Committed by Ingo Molnar Jun 13, 2017

x86/asm: Fix comment in return_from_SYSCALL_64()

On x86-64 __VIRTUAL_MASK_SHIFT depends on paging mode now.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
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: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-3-kirill.shutemov@linux.intel.com

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

parent e585513b

arch/x86/entry/entry_64.S

+2 −1

Original line number	Diff line number	Diff line
		@@ -265,7 +265,8 @@ return_from_SYSCALL_64:
		* If width of "canonical tail" ever becomes variable, this will need
		* to be updated to remain correct on both old and new CPUs.
		*
		* Change top 16 bits to be the sign-extension of 47th bit
		* Change top bits to match most significant bit (47th or 56th bit
		* depending on paging mode) in the address.
		*/
		shl $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
		sar $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx