From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3E2BC433FF for ; Fri, 9 Aug 2019 13:47:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A957A21783 for ; Fri, 9 Aug 2019 13:47:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565358464; bh=yTQUjLiGg98j1+bl78Zq1HHFkNqXgz6yiBPO75nQCiY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2LRzM302brRi8mKhcAuW4trvU0cB+0ebxUdbprhkWKEdq97YWorBx57/CEXfbG345 2QyJnECUqoIJKmTpO7kwfwiGxFOMceceLHfZdBsq8lvr6ilZBUuoD8Vt/usUSLBXsT d43A89OMKjGNLa8M0il6C1D8UWKd4XTQI2yoGgKU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407282AbfHINrn (ORCPT ); Fri, 9 Aug 2019 09:47:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:37720 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406833AbfHINrj (ORCPT ); Fri, 9 Aug 2019 09:47:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 60747217F4; Fri, 9 Aug 2019 13:47:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565358458; bh=yTQUjLiGg98j1+bl78Zq1HHFkNqXgz6yiBPO75nQCiY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gNbWFWQSvDHPl+/qGtGVrif5TEb4ppIbOPcQ4BCk4sohFfxcd9hRwSW35WOFZe3VE wXiOUT3DET+ql4hlMam977+PrsVZ0iSDOBSLs6AukYTml1HSg03KnoGAKwwVq4yqCq YIhQDIm7rcZytnVwFoMqHl3i/LONfJ+unizU//yE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Josh Poimboeuf , Thomas Gleixner , Ben Hutchings Subject: [PATCH 4.9 31/32] x86/entry/64: Use JMP instead of JMPQ Date: Fri, 9 Aug 2019 15:45:34 +0200 Message-Id: <20190809133923.929468509@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190809133922.945349906@linuxfoundation.org> References: <20190809133922.945349906@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Josh Poimboeuf commit 64dbc122b20f75183d8822618c24f85144a5a94d upstream. Somehow the swapgs mitigation entry code patch ended up with a JMPQ instruction instead of JMP, where only the short jump is needed. Some assembler versions apparently fail to optimize JMPQ into a two-byte JMP when possible, instead always using a 7-byte JMP with relocation. For some reason that makes the entry code explode with a #GP during boot. Change it back to "JMP" as originally intended. Fixes: 18ec54fdd6d1 ("x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations") Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- arch/x86/entry/entry_64.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -434,7 +434,7 @@ END(irq_entries_start) TRACE_IRQS_OFF CALL_enter_from_user_mode - jmpq 2f + jmp 2f 1: FENCE_SWAPGS_KERNEL_ENTRY 2: