From: Thomas Garnier via Virtualization Subject: [PATCH v3 02/27] x86: Use symbol name on bug table for PIE support Date: Wed, 23 May 2018 12:53:56 -0700 Message-ID: <20180523195421.180248-3-thgarnie@google.com> References: <20180523195421.180248-1-thgarnie@google.com> Reply-To: Thomas Garnier Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-arch@vger.kernel.org, kvm@vger.kernel.org, linux-pm@vger.kernel.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-sparse@vger.kernel.org, linux-crypto@vger.kernel.org, kernel-hardening@lists.openwall.com, xen-devel@lists.xenproject.org To: Herbert Xu , "David S . Miller" , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Peter Zijlstra , Josh Poimboeuf , Greg Kroah-Hartman , Thomas Garnier , Philippe Ombredanne , Kate Stewart , Arnaldo Carvalho de Melo , Yonghong Song , Andrey Ryabinin , Kees Cook , Tom Lendacky , "Kirill A . Shutemov" , Andy Lutomirski , Dominik Brodowski , Borislav Petkov , Borislav Petkov , "Rafael J . Wysocki" , Len Return-path: In-Reply-To: <20180523195421.180248-1-thgarnie@google.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: linux-crypto.vger.kernel.org Replace the %c constraint with %P. The %c is incompatible with PIE because it implies an immediate value whereas %P reference a symbol. Position Independent Executable (PIE) support will allow to extended the KASLR randomization range below the -2G memory limit. Signed-off-by: Thomas Garnier --- arch/x86/include/asm/bug.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h index 6804d6642767..3d690a4abf50 100644 --- a/arch/x86/include/asm/bug.h +++ b/arch/x86/include/asm/bug.h @@ -35,7 +35,7 @@ do { \ asm volatile("1:\t" ins "\n" \ ".pushsection __bug_table,\"aw\"\n" \ "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n" \ - "\t" __BUG_REL(%c0) "\t# bug_entry::file\n" \ + "\t" __BUG_REL(%P0) "\t# bug_entry::file\n" \ "\t.word %c1" "\t# bug_entry::line\n" \ "\t.word %c2" "\t# bug_entry::flags\n" \ "\t.org 2b+%c3\n" \ -- 2.17.0.441.gb46fe60e1d-goog