From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x225gpSL6xMj1Cdfc4MZ6J16tQlEMyQ0xIJ+FufSihBY6u48T83SerYDUjqeK8ZsLHD8Jkkxt ARC-Seal: i=1; a=rsa-sha256; t=1519218545; cv=none; d=google.com; s=arc-20160816; b=CCmpgIiu0agOvOUg8AbNduM1iFFL4jbXLztNsBBjfBv1UMNB7Xonv8duZIqdvR0H0t Gspif0uI1GMnWBEeJgp7HB9pqrToMyYjDokwXirEUX3nDLSaV5QK1+xIdnQFxI1MAcsy p11FBotjvmfrYqZIJbFqcfWob6hHhkKrjvkn14zDS9tdU9aCdePFkzCBdzRA5EMGJGyk D5+MoGuzlc8tnBqK0+Z29uQ3imP2ZIxAnSbPuuv4+moAjkSWe5/TkNdIQF0R0wrCL1KC Bv+gZgl6rWwnDyx4wmJygCEmnzAbtB29+kyuhAzbmQHmujsGBJFrgqHI6GWo4RDEnSpl o7UA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=/IBkwYmJfStbHh8cH0jgZHhJiVYv1CsEojAJesq14Q0=; b=glel3j0sGIS6vozXeaZg4MYg+C5Hh645zIH6qgrxPlSOqgpONcA2V8eIXz0uO/8Vq/ NqqmiT5wiF1GDdwrYbX9rBVx2Q38ZEuEmHNdobdEBUt7a0a6103DRLqpxav9cyL7mKA/ RRaCPQaM73gYeLgilk+2fem1yFaT8AYYdTiQpkqbaOTjeiJbm7O1NtC9q+cJBA7R4cP1 SSmmJOoWuHEF0HbEOFD8SEfSHuG3P+P/oHI6OcVzJWfUVHrvg6w0nORHN6q/rtnFSy9s vESXAEnIAJAkjrN7siNbZWUEBuV5Trz3x89xPejrtP3NL4MznCICWiua+tPaVa0H0KWp 0hxQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Borislav Petkov , Josh Poimboeuf , "Peter Zijlstra (Intel)" , Andy Lutomirski , Arjan van de Ven , Brian Gerst , Denys Vlasenko , "H. Peter Anvin" , Linus Torvalds , Thomas Gleixner , kbuild test robot , Ingo Molnar Subject: [PATCH 4.15 077/163] x86/debug, objtool: Annotate WARN()-related UD2 as reachable Date: Wed, 21 Feb 2018 13:48:26 +0100 Message-Id: <20180221124534.710771370@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180221124529.931834518@linuxfoundation.org> References: <20180221124529.931834518@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1593015701695663855?= X-GMAIL-MSGID: =?utf-8?q?1593016105294143556?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josh Poimboeuf commit 2b5db66862b95532cb6cca8165ae6eb73633cf85 upstream. By default, objtool assumes that a UD2 is a dead end. This is mainly because GCC 7+ sometimes inserts a UD2 when it detects a divide-by-zero condition. Now that WARN() is moving back to UD2, annotate the code after it as reachable so objtool can follow the code flow. Reported-by: Borislav Petkov Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kbuild test robot Link: http://lkml.kernel.org/r/0e483379275a42626ba8898117f918e1bf661e40.1518130694.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/bug.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/arch/x86/include/asm/bug.h +++ b/arch/x86/include/asm/bug.h @@ -77,7 +77,11 @@ do { \ unreachable(); \ } while (0) -#define __WARN_FLAGS(flags) _BUG_FLAGS(ASM_UD0, BUGFLAG_WARNING|(flags)) +#define __WARN_FLAGS(flags) \ +do { \ + _BUG_FLAGS(ASM_UD0, BUGFLAG_WARNING|(flags)); \ + annotate_reachable(); \ +} while (0) #include