From nobody Mon Feb 9 09:40:27 2026 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 436F7839EB for ; Fri, 28 Jun 2024 21:56:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719611796; cv=none; b=IcGgIr4Y4VljLfHVu/DS/JMXus6H8raIY8El1X4EbLpsgs/RigahRbj5g3RNW6mVZdIJcISvo09X1VlCgFrnX5qqDGYOOXC4JMN8OxWW3EfhRnxB3gIo6xxFtPtE8zY+9u17CaT1xlZrUB66+q0igdCuDOISXJtmoQtC6mgGE9I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719611796; c=relaxed/simple; bh=7UpWt0Wp9+zR/Uq/c6LkPQAMz/OkGruwVpBwVVZoADg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mH+GGH6Yz2/X9ndljsYQrCxNjQg9eC5kWW1Co9vFBCq0wb1FhnCMuKTTbaeZhpjoiMa60QxKtKet4k03tON3/++4kaM8tyewhRR/Fdl01SwCMpmmsVCgbwfjm4Ff34lNh30Ij9dLcjW8Z7D3BSX+AgBRJadomllzfGavK/9FPIM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=DAtIGtos; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="DAtIGtos" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1719611794; x=1751147794; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=7UpWt0Wp9+zR/Uq/c6LkPQAMz/OkGruwVpBwVVZoADg=; b=DAtIGtosxsTeaQunro5FD+CPt//iJqXhU4m9M2t9zP6/kCbcO8pX5EPn 3v1LcCucHb7Oy5hPfjU1aTptcMa7ZOaRhBlO1o3uqsHyONI/k66D3O/oP vqQgg2azZwGUxTUYhAXGPD/MqupHEqzvKubOoT86Exwkc5r5ufxXFjVRG KLbmFLUEFadpNgEmESd0qCxCsK5gc0NZDAF17k8onxPygRMVg/s8VvhBi JUVmwPUvn6VDoGJ8GDz4SyYQWZ6IRvgoC951XDX0qcEaGAmcBMOF0lDFZ MVpHFpycf3B4iRCwHy0Mm8x9iEgmo96qmMmpNoczeTDBoFaPQnP5qM08j w==; X-CSE-ConnectionGUID: 5qXAUNzLSf2ly8OiD6TKTw== X-CSE-MsgGUID: PAWa/jz0RZSFAeud6HZ7YQ== X-IronPort-AV: E=McAfee;i="6700,10204,11117"; a="16762591" X-IronPort-AV: E=Sophos;i="6.09,170,1716274800"; d="scan'208";a="16762591" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2024 14:56:28 -0700 X-CSE-ConnectionGUID: TsChAdLqQqu3dCT6nCbR1A== X-CSE-MsgGUID: phvLMc5gRxOQ/3Caw9K07A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.09,170,1716274800"; d="scan'208";a="68065663" Received: from agluck-desk3.sc.intel.com ([172.25.222.70]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2024 14:56:27 -0700 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Maciej Wieczor-Retman , Peter Newman , James Morse , Babu Moger , Drew Fustini , Dave Martin Cc: x86@kernel.org, linux-kernel@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH v23 10/19] x86/resctrl: Initialize on-stack struct rmid_read instances Date: Fri, 28 Jun 2024 14:56:10 -0700 Message-ID: <20240628215619.76401-11-tony.luck@intel.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240628215619.76401-1-tony.luck@intel.com> References: <20240628215619.76401-1-tony.luck@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" New semantics rely on some struct rmid_read members having NULL values to distinguish between the SNC and non-SNC scenarios. resctrl can thus no longer rely on this struct not being initialized properly. Initialize all on-stack declarations of struct rmid_read: rdtgroup_mondata_show() mbm_update() mkdir_mondata_subdir() to ensure that garbage values from the stack are not passed down to other functions. Remove redundant rr->val =3D 0; from mon_event_read() and rr.first =3D fals= e; from mbm_update() since the rmid_read structure is cleared by compiler. Signed-off-by: Tony Luck Reviewed-by: Reinette Chatre --- arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 3 +-- arch/x86/kernel/cpu/resctrl/monitor.c | 3 +-- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +- 3 files changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cp= u/resctrl/ctrlmondata.c index 3b9383612c35..4d76ff31a9e0 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -529,7 +529,6 @@ void mon_event_read(struct rmid_read *rr, struct rdt_re= source *r, rr->evtid =3D evtid; rr->r =3D r; rr->d =3D d; - rr->val =3D 0; rr->first =3D first; rr->arch_mon_ctx =3D resctrl_arch_mon_ctx_alloc(r, evtid); if (IS_ERR(rr->arch_mon_ctx)) { @@ -557,12 +556,12 @@ int rdtgroup_mondata_show(struct seq_file *m, void *a= rg) { struct kernfs_open_file *of =3D m->private; struct rdt_domain_hdr *hdr; + struct rmid_read rr =3D {0}; struct rdt_mon_domain *d; u32 resid, evtid, domid; struct rdtgroup *rdtgrp; struct rdt_resource *r; union mon_data_bits md; - struct rmid_read rr; int ret =3D 0; =20 rdtgrp =3D rdtgroup_kn_lock_live(of->kn); diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/re= sctrl/monitor.c index ff4e74594a19..ca309c93a56b 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -780,9 +780,8 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct= rdt_mon_domain *dom_mbm) static void mbm_update(struct rdt_resource *r, struct rdt_mon_domain *d, u32 closid, u32 rmid) { - struct rmid_read rr; + struct rmid_read rr =3D {0}; =20 - rr.first =3D false; rr.r =3D r; rr.d =3D d; =20 diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r= esctrl/rdtgroup.c index 70d41a8fd788..d0443589cd86 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -3029,10 +3029,10 @@ static int mkdir_mondata_subdir(struct kernfs_node = *parent_kn, struct rdt_mon_domain *d, struct rdt_resource *r, struct rdtgroup *prgrp) { + struct rmid_read rr =3D {0}; union mon_data_bits priv; struct kernfs_node *kn; struct mon_evt *mevt; - struct rmid_read rr; char name[32]; int ret; =20 --=20 2.45.2