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 AF6DFCCA48D for ; Tue, 7 Jun 2022 21:06:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379500AbiFGVGB (ORCPT ); Tue, 7 Jun 2022 17:06:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358488AbiFGUHA (ORCPT ); Tue, 7 Jun 2022 16:07:00 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 028A91C4269; Tue, 7 Jun 2022 11:26:00 -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 4D076612F2; Tue, 7 Jun 2022 18:26:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58987C385A2; Tue, 7 Jun 2022 18:25:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654626359; bh=4FWVvpGIVHGySV3NM6oA2OJC61WladjaOASJ3N08TN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jbE7BjJ5gTsGkEcolIRXoxUzuQjejm1eaJkp6y+TmsWpLVJiVFbVhEW3CFXMJ0HzG 9mJs3I2heyOgIF9PTltY7X8jluMNxrYCIQ/IN0hshh1SoUD8JNKtLVPV3VgTA2j2as lB9z99KPIj2x0B7D6kBxK7KB6vISkVjLkulUc+ZA= 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 5.17 351/772] perf/amd/ibs: Use interrupt regs ip for stack unwinding Date: Tue, 7 Jun 2022 18:59:03 +0200 Message-Id: <20220607164959.362821184@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164948.980838585@linuxfoundation.org> References: <20220607164948.980838585@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 367ca899e6e8..2704ec1e42a3 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -304,6 +304,16 @@ 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; } @@ -687,6 +697,14 @@ 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