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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0BFF5C54E64 for ; Mon, 25 Mar 2024 06:45:40 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=ga1gA8BA; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4V33NL5HQgz3vnC for ; Mon, 25 Mar 2024 17:45:38 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=ga1gA8BA; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=intel.com (client-ip=192.198.163.9; helo=mgamail.intel.com; envelope-from=adrian.hunter@intel.com; receiver=lists.ozlabs.org) Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4V33HN0yY8z3d3g for ; Mon, 25 Mar 2024 17:41:19 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1711348880; x=1742884880; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Exf/ex05wg/ZdHrQtagsjpQZFoomRp7dCTSrSntMNmc=; b=ga1gA8BAKzQb7oh/Iwa+rYdXezmDf6TNDYvHNqZfQktUh0I/P7Nktcm1 dmtHhCAywTpPtdmk+Hh6t0CfGwNK/K1BC3Ib1t3sbhkXx91NkGxayDbBX UYQ3vJrlng0j1BzYnIiWlaj0ySPNBmeuLPYjrqg7JV9655eb25M/+O8to IXbW4QApbWkLAVVMODGcmuvsWcspr0MWLbQjEN3zQdfAzPkCo6sqwfAHc s4FJB/AV6BZ8Yue7sz9rgN3dUwSK0hgiWLRjobw9Fa99lB6F2xMC+ZvfG Sk69bspV4vaANF9NUhmiaBK6zaTdAHAnOSNoPLTw7UnNwWU6xLte+XNY9 w==; X-IronPort-AV: E=McAfee;i="6600,9927,11023"; a="17065189" X-IronPort-AV: E=Sophos;i="6.07,152,1708416000"; d="scan'208";a="17065189" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2024 23:41:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,152,1708416000"; d="scan'208";a="38629593" Received: from ahunter6-mobl1.ger.corp.intel.com (HELO ahunter-VirtualBox.home\044ger.corp.intel.com) ([10.251.211.155]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2024 23:41:11 -0700 From: Adrian Hunter To: Thomas Gleixner Subject: [PATCH V2 06/19] vdso: Add vdso_data::max_cycles Date: Mon, 25 Mar 2024 08:40:10 +0200 Message-Id: <20240325064023.2997-7-adrian.hunter@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240325064023.2997-1-adrian.hunter@intel.com> References: <20240325064023.2997-1-adrian.hunter@intel.com> MIME-Version: 1.0 Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Dave Hansen , John Stultz , "H. Peter Anvin" , Alexander Gordeev , Vincenzo Frascino , linux-s390@vger.kernel.org, Arnd Bergmann , x86@kernel.org, "Aneesh Kumar K.V" , Ingo Molnar , "Naveen N. Rao" , Christian Borntraeger , Vasily Gorbik , Heiko Carstens , Nicholas Piggin , Borislav Petkov , Andy Lutomirski , Bjorn Helgaas , Anna-Maria Behnsen , Stephen Boyd , Randy Dunlap , linux-kernel@vger.kernel.org, Sven Schnelle , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Add vdso_data::max_cycles in preparation to use it to detect potential multiplication overflow. Suggested-by: Thomas Gleixner Signed-off-by: Adrian Hunter --- include/vdso/datapage.h | 4 ++++ kernel/time/vsyscall.c | 6 ++++++ 2 files changed, 10 insertions(+) diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h index 5d5c0b8efff2..6c3d67d6b758 100644 --- a/include/vdso/datapage.h +++ b/include/vdso/datapage.h @@ -67,6 +67,7 @@ struct vdso_timestamp { * @seq: timebase sequence counter * @clock_mode: clock mode * @cycle_last: timebase at clocksource init + * @max_cycles: maximum cycles which won't overflow 64bit multiplication * @mask: clocksource mask * @mult: clocksource multiplier * @shift: clocksource shift @@ -98,6 +99,9 @@ struct vdso_data { s32 clock_mode; u64 cycle_last; +#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT + u64 max_cycles; +#endif u64 mask; u32 mult; u32 shift; diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index f0d5062d9cbc..9193d6133e5d 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -22,10 +22,16 @@ static inline void update_vdso_data(struct vdso_data *vdata, u64 nsec, sec; vdata[CS_HRES_COARSE].cycle_last = tk->tkr_mono.cycle_last; +#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT + vdata[CS_HRES_COARSE].max_cycles = tk->tkr_mono.clock->max_cycles; +#endif vdata[CS_HRES_COARSE].mask = tk->tkr_mono.mask; vdata[CS_HRES_COARSE].mult = tk->tkr_mono.mult; vdata[CS_HRES_COARSE].shift = tk->tkr_mono.shift; vdata[CS_RAW].cycle_last = tk->tkr_raw.cycle_last; +#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT + vdata[CS_RAW].max_cycles = tk->tkr_raw.clock->max_cycles; +#endif vdata[CS_RAW].mask = tk->tkr_raw.mask; vdata[CS_RAW].mult = tk->tkr_raw.mult; vdata[CS_RAW].shift = tk->tkr_raw.shift; -- 2.34.1