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=-14.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=no 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 E0728C433DF for ; Sat, 17 Oct 2020 06:03:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAC6B2072C for ; Sat, 17 Oct 2020 06:03:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="WuhlseqJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2436904AbgJQGDC (ORCPT ); Sat, 17 Oct 2020 02:03:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2411569AbgJQGBh (ORCPT ); Sat, 17 Oct 2020 02:01:37 -0400 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A6CEC0613D3 for ; Fri, 16 Oct 2020 17:12:44 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id q15so2617412qkq.23 for ; Fri, 16 Oct 2020 17:12:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=0SzVqODEfPVXxLTAWYh1OlMRZX67EtQRCd+LR3qS49c=; b=WuhlseqJkkPmSyZw616Hrf+g3JLaplGgcP+WbLNqPy6pbqoUqVy2fZfRmPjkKnlNEF a5QjECu3iU010I4z4m5sv9yOYLjtgYQMD/ntbgYb0y7oaqRCzmy2Jhr0dSTYhJP9QDev EABizo8Mme8p3TdOVqWL5im2eC+Shw6NDyno9Z+iAkK0YzHTLLQ20+l7sz/2txyxDbtN kv8S9RWCC9Rte4uKn/cBRjsG1J8fN5X/JRpTFdBNv79AQ/ntKnI9Gz3mlw1vqxnB9Ixz WWMeIe5grQwW+JAz61iF76EpV/juD7Z3uLyAlFgBDg4FPo6mb2jDawciNLJtNzKVYiE1 UbDw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=0SzVqODEfPVXxLTAWYh1OlMRZX67EtQRCd+LR3qS49c=; b=DCnomnNc3gWuA3SC8zNIImf2qH0z3ahPbRKKNj19XAGdubr87qNG0X4iari9NrvBSh f8CKVZ1xw4bg0nUib8UvkKiX91Q+WcLSBFi2UBbsgrAbe1Si1WTQXcueGg9lSogdGv87 mum0hbqT072WldKL6r0VCTHouiqQMncUnBMmaNYCIBUi8NGNtnetYIiPWED0RYiPJEAW /IY7zpg1MiX4jYKqD3vANEJepo7ZGzAC4QUWu80RNxDUyn3ejgcvqqdeqO0HWzEhLb0h MmJ+lJvgw65YMCOWdipNtREkdwYwFV6fHIzVagKNAqq4QHVlcyjkxhWwEWKvtQZRgWoI rB+g== X-Gm-Message-State: AOAM532T/0ZRznHN/qrcgZWiCZlV62//XFht3gFcUfatAHKeZx4tuJdq 73kL/mq8of0TlTLmB/RPOONZqXY= X-Google-Smtp-Source: ABdhPJwrcG+HjhDPcsvVqMBOCzJnFkmyrsDDTznxLj+oymEZ6nBA7SBVRkAeE4Jure8saQqIjl/72hc= Sender: "pcc via sendgmr" X-Received: from pcc-desktop.svl.corp.google.com ([2620:15c:2ce:0:7220:84ff:fe09:385a]) (user=pcc job=sendgmr) by 2002:a05:6214:943:: with SMTP id dn3mr6291415qvb.45.1602893563003; Fri, 16 Oct 2020 17:12:43 -0700 (PDT) Date: Fri, 16 Oct 2020 17:12:25 -0700 Message-Id: Mime-Version: 1.0 X-Mailer: git-send-email 2.29.0.rc1.297.gfa9743e501-goog Subject: [PATCH v12 0/8] arm64: expose FAR_EL1 tag bits in siginfo From: Peter Collingbourne To: Catalin Marinas , Evgenii Stepanov , Kostya Serebryany , Vincenzo Frascino , Dave Martin , Will Deacon , Oleg Nesterov , "Eric W. Biederman" , "James E.J. Bottomley" Cc: Peter Collingbourne , Linux ARM , Kevin Brodsky , Andrey Konovalov , Richard Henderson , linux-api@vger.kernel.org, Helge Deller , David Spickett Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org The kernel currently clears the tag bits (i.e. bits 56-63) in the fault address exposed via siginfo.si_addr and sigcontext.fault_address. However, the tag bits may be needed by tools in order to accurately diagnose memory errors, such as HWASan [1] or future tools based on the Memory Tagging Extension (MTE). We should not stop clearing these bits in the existing fault address fields, because there may be existing userspace applications that are expecting the tag bits to be cleared. Instead, create a new pair of union fields in siginfo._sigfault, and store the tag bits of FAR_EL1 there, together with a mask specifying which bits are valid. However, one does not simply add fields to siginfo, at least not without a mechanism for userspace to detect that they are present and valid. Therefore, the first seven patches in this series introduce a mechanism for userspace to detect the presence of our new siginfo fields, and the last patch uses it to advertise the presence of said fields. The series can be viewed on Gerrit here: https://linux-review.googlesource.com/q/Ia8876bad8c798e0a32df7c2ce1256c4771c81446 [1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html Helge Deller (1): parisc: Drop parisc special case for __sighandler_t Peter Collingbourne (7): parisc: start using signal-defs.h arch: move SA_* definitions to generic headers signal: clear non-uapi flag bits when passing/returning sa_flags signal: define the SA_UNSUPPORTED bit in sa_flags signal: deduplicate code dealing with common _sigfault fields signal: define the field siginfo.si_xflags arm64: expose FAR_EL1 tag bits in siginfo Documentation/arm64/tagged-pointers.rst | 21 +++- arch/alpha/include/uapi/asm/signal.h | 14 --- arch/arm/include/asm/signal.h | 2 + arch/arm/include/uapi/asm/signal.h | 28 +---- arch/arm64/include/asm/exception.h | 2 +- arch/arm64/include/asm/signal.h | 19 +++ arch/arm64/include/asm/system_misc.h | 2 +- arch/arm64/include/asm/traps.h | 6 +- arch/arm64/kernel/debug-monitors.c | 5 +- arch/arm64/kernel/entry-common.c | 2 - arch/arm64/kernel/ptrace.c | 7 +- arch/arm64/kernel/sys_compat.c | 5 +- arch/arm64/kernel/traps.c | 29 ++--- arch/arm64/mm/fault.c | 68 ++++++----- arch/h8300/include/uapi/asm/signal.h | 24 ---- arch/ia64/include/uapi/asm/signal.h | 24 ---- arch/m68k/include/uapi/asm/signal.h | 24 ---- arch/mips/include/uapi/asm/signal.h | 12 -- arch/parisc/include/asm/signal.h | 2 + arch/parisc/include/uapi/asm/signal.h | 34 +----- arch/powerpc/include/uapi/asm/signal.h | 24 ---- arch/powerpc/platforms/powernv/vas-fault.c | 1 + arch/s390/include/uapi/asm/signal.h | 24 ---- arch/sparc/include/uapi/asm/signal.h | 4 +- arch/x86/include/uapi/asm/signal.h | 24 ---- arch/x86/kernel/signal_compat.c | 19 +-- arch/xtensa/include/uapi/asm/signal.h | 24 ---- include/linux/compat.h | 4 + include/linux/signal.h | 29 +++++ include/linux/signal_types.h | 12 ++ include/uapi/asm-generic/siginfo.h | 14 +++ include/uapi/asm-generic/signal-defs.h | 58 +++++++++ include/uapi/asm-generic/signal.h | 29 ----- include/uapi/linux/ptrace.h | 12 ++ kernel/ptrace.c | 32 ++++- kernel/signal.c | 134 +++++++++++---------- 36 files changed, 345 insertions(+), 429 deletions(-) create mode 100644 arch/arm64/include/asm/signal.h -- 2.29.0.rc1.297.gfa9743e501-goog