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 01C6DC433EF for ; Fri, 28 Jan 2022 16:23:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350085AbiA1QXs (ORCPT ); Fri, 28 Jan 2022 11:23:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350059AbiA1QXp (ORCPT ); Fri, 28 Jan 2022 11:23:45 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89405C06173B for ; Fri, 28 Jan 2022 08:23:45 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 16A4E61F1E for ; Fri, 28 Jan 2022 16:23:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D0F7C340E7; Fri, 28 Jan 2022 16:23:44 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.95) (envelope-from ) id 1nDU2J-00ASyY-JP; Fri, 28 Jan 2022 11:23:43 -0500 Message-ID: <20220128162343.435311583@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 28 Jan 2022 11:18:03 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Russell King , Yinan Liu , Ard Biesheuvel , Kees Cook , Sachin Sant , Mark Rutland Subject: [for-linus][PATCH 01/10] ftrace: Have architectures opt-in for mcount build time sorting References: <20220128161802.711119424@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Steven Rostedt (Google)" First S390 complained that the sorting of the mcount sections at build time caused the kernel to crash on their architecture. Now PowerPC is complaining about it too. And also ARM64 appears to be having issues. It may be necessary to also update the relocation table for the values in the mcount table. Not only do we have to sort the table, but also update the relocations that may be applied to the items in the table. If the system is not relocatable, then it is fine to sort, but if it is, some architectures may have issues (although x86 does not as it shifts all addresses the same). Add a HAVE_BUILDTIME_MCOUNT_SORT that an architecture can set to say it is safe to do the sorting at build time. Also update the config to compile in build time sorting in the sorttable code in scripts/ to depend on CONFIG_BUILDTIME_MCOUNT_SORT. Link: https://lore.kernel.org/all/944D10DA-8200-4BA9-8D0A-3BED9AA99F82@linux.ibm.com/ Link: https://lkml.kernel.org/r/20220127153821.3bc1ac6e@gandalf.local.home Cc: Ingo Molnar Cc: Andrew Morton Cc: Russell King Cc: Yinan Liu Cc: Ard Biesheuvel Cc: Kees Cook Reported-by: Sachin Sant Reviewed-by: Mark Rutland Tested-by: Mark Rutland [arm64] Tested-by: Sachin Sant Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init") Signed-off-by: Steven Rostedt (Google) --- arch/arm/Kconfig | 1 + arch/x86/Kconfig | 1 + kernel/trace/Kconfig | 8 +++++++- scripts/Makefile | 2 +- 4 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index fabe39169b12..4c97cb40eebb 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -83,6 +83,7 @@ config ARM select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32 select HAVE_CONTEXT_TRACKING select HAVE_C_RECORDMCOUNT + select HAVE_BUILDTIME_MCOUNT_SORT select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL select HAVE_DMA_CONTIGUOUS if MMU select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ebe8fc76949a..9f5bd41bf660 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -186,6 +186,7 @@ config X86 select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING select HAVE_C_RECORDMCOUNT select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION + select HAVE_BUILDTIME_MCOUNT_SORT select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 752ed89a293b..a5eb5e7fd624 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -70,10 +70,16 @@ config HAVE_C_RECORDMCOUNT help C version of recordmcount available? +config HAVE_BUILDTIME_MCOUNT_SORT + bool + help + An architecture selects this if it sorts the mcount_loc section + at build time. + config BUILDTIME_MCOUNT_SORT bool default y - depends on BUILDTIME_TABLE_SORT && !S390 + depends on HAVE_BUILDTIME_MCOUNT_SORT && DYNAMIC_FTRACE help Sort the mcount_loc section at build time. diff --git a/scripts/Makefile b/scripts/Makefile index ecd3acacd0ec..ce5aa9030b74 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -25,7 +25,7 @@ HOSTCFLAGS_sorttable.o += -I$(srctree)/tools/arch/x86/include HOSTCFLAGS_sorttable.o += -DUNWINDER_ORC_ENABLED endif -ifdef CONFIG_DYNAMIC_FTRACE +ifdef CONFIG_BUILDTIME_MCOUNT_SORT HOSTCFLAGS_sorttable.o += -DMCOUNT_SORT_ENABLED endif -- 2.33.0