From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com ([134.134.136.65]:28580 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754083AbcLHQWd (ORCPT ); Thu, 8 Dec 2016 11:22:33 -0500 From: "Kirill A. Shutemov" Subject: [RFC, PATCHv1 16/28] x86/asm: remove __VIRTUAL_MASK_SHIFT==47 assert Date: Thu, 8 Dec 2016 19:21:38 +0300 Message-ID: <20161208162150.148763-18-kirill.shutemov@linux.intel.com> In-Reply-To: <20161208162150.148763-1-kirill.shutemov@linux.intel.com> References: <20161208162150.148763-1-kirill.shutemov@linux.intel.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Linus Torvalds , Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , Arnd Bergmann , "H. Peter Anvin" Cc: Andi Kleen , Dave Hansen , Andy Lutomirski , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Message-ID: <20161208162138.pjdppGQtuaUx06XjSeU4lZJaJIBvQzk32E--BcaXLZc@z> We don't need it anymore. 17be0aec74fb ("x86/asm/entry/64: Implement better check for canonical addresses") made canonical address check generic wrt. address width. Signed-off-by: Kirill A. Shutemov --- arch/x86/entry/entry_64.S | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 02fff3ebfb87..92a6753f8c85 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -267,12 +267,9 @@ 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 */ - .ifne __VIRTUAL_MASK_SHIFT - 47 - .error "virtual address width changed -- SYSRET checks need update" - .endif - - /* Change top 16 bits to be the sign-extension of 47th bit */ shl $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx sar $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx -- 2.10.2