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 718A3C433EF for ; Mon, 13 Jun 2022 11:58:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357143AbiFML6R (ORCPT ); Mon, 13 Jun 2022 07:58:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356621AbiFMLur (ORCPT ); Mon, 13 Jun 2022 07:50:47 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8AC4022B27; Mon, 13 Jun 2022 03:54:39 -0700 (PDT) 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 26CF160F00; Mon, 13 Jun 2022 10:54:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38F2BC34114; Mon, 13 Jun 2022 10:54:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655117678; bh=aumf9yAoZ5XHJ9DWTFSBRcccitJ4jRF/Eo0ETcWmvzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XOOOXAFs+qyCRocM6qwGi//r7Duzawsmq8SZtNiBOl/whZQcG1+9uHWWVUYD347sW 28fMfKXdsfWrFOjx6Ec1cKwELD7wDNG5UOIL8AVPEqXlAoe05v8HeHBicAAdPEtgDj T3CCSGcLwOxAaPGWhJkPZXDYp8xG/uWyXrSRj9KE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Monakhov , Peter Zijlstra , Ravi Bangoria , Sasha Levin Subject: [PATCH 4.19 092/287] perf/amd/ibs: Use interrupt regs ip for stack unwinding Date: Mon, 13 Jun 2022 12:08:36 +0200 Message-Id: <20220613094926.668894523@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094923.832156175@linuxfoundation.org> References: <20220613094923.832156175@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ravi Bangoria [ Upstream commit 3d47083b9ff46863e8374ad3bb5edb5e464c75f8 ] IbsOpRip is recorded when IBS interrupt is triggered. But there is a skid from the time IBS interrupt gets triggered to the time the interrupt is presented to the core. Meanwhile processor would have moved ahead and thus IbsOpRip will be inconsistent with rsp and rbp recorded as part of the interrupt regs. This causes issues while unwinding stack using the ORC unwinder as it needs consistent rip, rsp and rbp. Fix this by using rip from interrupt regs instead of IbsOpRip for stack unwinding. Fixes: ee9f8fce99640 ("x86/unwind: Add the ORC unwinder") Reported-by: Dmitry Monakhov Suggested-by: Peter Zijlstra Signed-off-by: Ravi Bangoria Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220429051441.14251-1-ravi.bangoria@amd.com Signed-off-by: Sasha Levin --- arch/x86/events/amd/ibs.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c index 2d9e1372b070..d157d0adef06 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -324,6 +324,16 @@ static int perf_ibs_init(struct perf_event *event) hwc->config_base = perf_ibs->msr; hwc->config = config; + /* + * rip recorded by IbsOpRip will not be consistent with rsp and rbp + * recorded as part of interrupt regs. Thus we need to use rip from + * interrupt regs while unwinding call stack. Setting _EARLY flag + * makes sure we unwind call-stack before perf sample rip is set to + * IbsOpRip. + */ + if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) + event->attr.sample_type |= __PERF_SAMPLE_CALLCHAIN_EARLY; + return 0; } @@ -693,6 +703,14 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs) data.raw = &raw; } + /* + * rip recorded by IbsOpRip will not be consistent with rsp and rbp + * recorded as part of interrupt regs. Thus we need to use rip from + * interrupt regs while unwinding call stack. + */ + if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) + data.callchain = perf_callchain(event, iregs); + throttle = perf_event_overflow(event, &data, ®s); out: if (throttle) { -- 2.35.1