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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7778FC433EF for ; Sat, 29 Jan 2022 12:02:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243333AbiA2MCz (ORCPT ); Sat, 29 Jan 2022 07:02:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48968 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231668AbiA2MCz (ORCPT ); Sat, 29 Jan 2022 07:02:55 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12AE2C061714 for ; Sat, 29 Jan 2022 04:02:55 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D04E2B822B2 for ; Sat, 29 Jan 2022 12:02:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F1425C340E5; Sat, 29 Jan 2022 12:02:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643457772; bh=ZBInDk01bBocxzvhspw/FGM6bwzjwx3Pz0aNQol5ta0=; h=Subject:To:Cc:From:Date:From; b=gzSW/9LgjXJ8Rp4kXbuIujtbreKdbKqfcLmfa9qiuNMqLRACWoReGlGL+w8PXNkNG 5g8wYxFT84OLwrnlgkQYsxoAeccwhKk0qyIbb4//8phH7Gn/nJzcQ5UXliyIwyPkiT iI8F2xNW/nsnvtDF5fJFYZSVZquWeNkDqDEnOvBw= Subject: FAILED: patch "[PATCH] s390/module: fix loading modules with a lot of relocations" failed to apply to 4.4-stable tree To: iii@linux.ibm.com, andrea.righi@canonical.com, borntraeger@linux.ibm.com, gor@linux.ibm.com, hca@linux.ibm.com Cc: From: Date: Sat, 29 Jan 2022 13:02:49 +0100 Message-ID: <164345776983183@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f3b7e73b2c6619884351a3a0a7468642f852b8a2 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Wed, 19 Jan 2022 19:26:37 +0100 Subject: [PATCH] s390/module: fix loading modules with a lot of relocations If the size of the PLT entries generated by apply_rela() exceeds 64KiB, the first ones can no longer reach __jump_r1 with brc. Fix by using brcl. An alternative solution is to add a __jump_r1 copy after every 64KiB, however, the space savings are quite small and do not justify the additional complexity. Fixes: f19fbd5ed642 ("s390: introduce execute-trampolines for branches") Cc: stable@vger.kernel.org Reported-by: Andrea Righi Signed-off-by: Ilya Leoshkevich Reviewed-by: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Signed-off-by: Heiko Carstens diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c index d52d85367bf7..b032e556eeb7 100644 --- a/arch/s390/kernel/module.c +++ b/arch/s390/kernel/module.c @@ -33,7 +33,7 @@ #define DEBUGP(fmt , ...) #endif -#define PLT_ENTRY_SIZE 20 +#define PLT_ENTRY_SIZE 22 void *module_alloc(unsigned long size) { @@ -341,27 +341,26 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab, case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */ case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */ if (info->plt_initialized == 0) { - unsigned int insn[5]; - unsigned int *ip = me->core_layout.base + - me->arch.plt_offset + - info->plt_offset; - - insn[0] = 0x0d10e310; /* basr 1,0 */ - insn[1] = 0x100a0004; /* lg 1,10(1) */ + unsigned char insn[PLT_ENTRY_SIZE]; + char *plt_base; + char *ip; + + plt_base = me->core_layout.base + me->arch.plt_offset; + ip = plt_base + info->plt_offset; + *(int *)insn = 0x0d10e310; /* basr 1,0 */ + *(int *)&insn[4] = 0x100c0004; /* lg 1,12(1) */ if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable) { - unsigned int *ij; - ij = me->core_layout.base + - me->arch.plt_offset + - me->arch.plt_size - PLT_ENTRY_SIZE; - insn[2] = 0xa7f40000 + /* j __jump_r1 */ - (unsigned int)(u16) - (((unsigned long) ij - 8 - - (unsigned long) ip) / 2); + char *jump_r1; + + jump_r1 = plt_base + me->arch.plt_size - + PLT_ENTRY_SIZE; + /* brcl 0xf,__jump_r1 */ + *(short *)&insn[8] = 0xc0f4; + *(int *)&insn[10] = (jump_r1 - (ip + 8)) / 2; } else { - insn[2] = 0x07f10000; /* br %r1 */ + *(int *)&insn[8] = 0x07f10000; /* br %r1 */ } - insn[3] = (unsigned int) (val >> 32); - insn[4] = (unsigned int) val; + *(long *)&insn[14] = val; write(ip, insn, sizeof(insn)); info->plt_initialized = 1;