From patchwork Wed Mar 24 11:24:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marco Elver X-Patchwork-Id: 12160813 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 1936BC433E4 for ; Wed, 24 Mar 2021 11:26:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC69A61A1A for ; Wed, 24 Mar 2021 11:26:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234822AbhCXL0J (ORCPT ); Wed, 24 Mar 2021 07:26:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38106 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234990AbhCXLZh (ORCPT ); Wed, 24 Mar 2021 07:25:37 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA8C7C0613DF for ; Wed, 24 Mar 2021 04:25:36 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id m11so949819qtx.19 for ; Wed, 24 Mar 2021 04:25:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=yTQtN+ZnokJzpQVm2BawzGlkCzsy9LGpOuPbrdojTxI=; b=eB0ckdgLY/9Mw7+c6wAMy4us/PB/YzfvC+tjuW6EEFemR43arcp3phQ/zVb+Cjf3L6 kaphLRablv22cVVyXqwnAgfsL9bHsNK/McsF8kXgkjWGDCkqlD2LviOVeeYxSD4Cgc7S N5QTatiiBWUzZRX1RBYVDomafcyIzAFl6YiABcQwfd9FKnW2tS+3QnWAsic68aFgZrwx Hp4jWqv0Sva60F0SWTWBJvvSt3G30DxVxVY67PD02YygcoZYEP3JvuOMz+L0sinSO/+5 hf2OhTpcNPGhFyAwcHDpY3+eJjZ9fXfzrNcD5PY/7rtTrNahBK8qDRBr3OagakKe6U5A XoGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=yTQtN+ZnokJzpQVm2BawzGlkCzsy9LGpOuPbrdojTxI=; b=KjvuHLqaDWLlz77gEsvjewpDt5uOohrz/sJTPa9MWbz977PPG5sBJmU8o1Njib+h1W exnDwZQWGeltOlGXhjLRP31G+ERR+XWqiZlUwut9J9drY4OGEcd1zJS6tCPaZ+zt0y9u jmTPslHrfG5alG61a/bOSGRwByh7zowoFvSMu6dAsltEz7eHkhbo4cNwOmZbrvQ8Yg77 VnqSe036uzkn/ssjSPcGwDMxyMFnBo15huG/rdQk0zGxrKgEM1MRHGrvQFd9YKgapFeK YLnZ0bHb6Pb1rY7SK0HEwYkT0IsYVjg7gilPni9b5Ynyz5n4Z0CEBXBO0VWu0BcdEIMm 0/Jw== X-Gm-Message-State: AOAM531NYfLYPf+x4i7bPECsWqO7RQEc9rewUFWpAzaGxNzRmhXur6JY QN3hfvVQ+vgJ/3p1K/VFHbYoARTqrw== X-Google-Smtp-Source: ABdhPJzRVukCVxBGVmxIhQ60T0lTvl+h5lsKxkFEL8Sjs6BBC73DCi1y8PZi7hM+RtQxq4YiLP1oMmBNWg== X-Received: from elver.muc.corp.google.com ([2a00:79e0:15:13:6489:b3f0:4af:af0]) (user=elver job=sendgmr) by 2002:ad4:50d0:: with SMTP id e16mr2718629qvq.37.1616585136104; Wed, 24 Mar 2021 04:25:36 -0700 (PDT) Date: Wed, 24 Mar 2021 12:24:59 +0100 In-Reply-To: <20210324112503.623833-1-elver@google.com> Message-Id: <20210324112503.623833-8-elver@google.com> Mime-Version: 1.0 References: <20210324112503.623833-1-elver@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH v3 07/11] perf: Add breakpoint information to siginfo on SIGTRAP From: Marco Elver To: elver@google.com, peterz@infradead.org, alexander.shishkin@linux.intel.com, acme@kernel.org, mingo@redhat.com, jolsa@redhat.com, mark.rutland@arm.com, namhyung@kernel.org, tglx@linutronix.de Cc: glider@google.com, viro@zeniv.linux.org.uk, arnd@arndb.de, christian@brauner.io, dvyukov@google.com, jannh@google.com, axboe@kernel.dk, mascasa@google.com, pcc@google.com, irogers@google.com, kasan-dev@googlegroups.com, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-kselftest@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Encode information from breakpoint attributes into siginfo_t, which helps disambiguate which breakpoint fired. Note, providing the event fd may be unreliable, since the event may have been modified (via PERF_EVENT_IOC_MODIFY_ATTRIBUTES) between the event triggering and the signal being delivered to user space. Signed-off-by: Marco Elver --- v2: * Add comment about si_perf==0. --- kernel/events/core.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 1e4c949bf75f..0316d39e8c8f 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6399,6 +6399,22 @@ static void perf_sigtrap(struct perf_event *event) info.si_signo = SIGTRAP; info.si_code = TRAP_PERF; info.si_errno = event->attr.type; + + switch (event->attr.type) { + case PERF_TYPE_BREAKPOINT: + info.si_addr = (void *)(unsigned long)event->attr.bp_addr; + info.si_perf = (event->attr.bp_len << 16) | (u64)event->attr.bp_type; + break; + default: + /* + * No additional info set (si_perf == 0). + * + * Adding new cases for event types to set si_perf to a + * non-constant value must ensure that si_perf != 0. + */ + break; + } + force_sig_info(&info); }