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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 A4848C43458 for ; Fri, 10 Jul 2026 11:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=OrrA01oBiydfU/wKB+VGgAejpF5U9FOglxu6FBKF8p8=; b=zcGh3JNgUXWv42OveoBqYD64OB F0urVS/9pPo3QqWST4AQEkywPJweOjfKDaP2guAkdUl5kkTN2MdKFPsuqSygG7StQiBU98VibIQ4O RJKdbymgrpDbXDHHwDbzXEP4IjVDrQwsT567gICHebifmzlxwMErG+hfB8sdpjnPc8px37Ch82u8h To03VeMUfGelsdkH33EdJDD8pYUp4e2vlYL4j6lU9Yz/eimo5z0UPLTrLXsIFOmloN+1+gmm/hxf6 vRPR9asWSwTDLW+nYN9T01DVkoVCMuBY/obCRN6lAt1sJQhHeI28q283pMNV03MFMmfzT7prQuu02 f9vlLOxw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wi9pw-00000004rp3-3Kie; Fri, 10 Jul 2026 11:56:08 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wi9pr-00000004rl4-1Z5V for linux-arm-kernel@lists.infradead.org; Fri, 10 Jul 2026 11:56:04 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 592661FC7; Fri, 10 Jul 2026 04:55:58 -0700 (PDT) Received: from e134344.cambridge.arm.com (e134344.arm.com [10.2.212.8]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 64C083F85F; Fri, 10 Jul 2026 04:56:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783684562; bh=nuBpyWDhg01mGE5l/NpZBdUueEbff+jPNB0ll2EAWDs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bpo82XloTyfop1H+/X+gjvyK+b+6o4mN8JjbsxDvVKtrkQ08SqcPmDMPnyR+w5tqd 4iSOxN6020bi8CL0Q9g2l847PV2Z0Iog24QeDa5KITH9PfQcCDLaW8DgDQ4QhDgLeO C5PHcqhkZhX6h3z2dXfFq9R/7moDeTjXEOH5r1X8= From: Ben Horgan To: ben.horgan@arm.com Cc: james.morse@arm.com, reinette.chatre@intel.com, fenghuay@nvidia.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dave.martin@arm.com, andre.przywara@arm.com Subject: [PATCH v1 04/11] arm_mpam: Add missing mon_sel locking in MBWU restore Date: Fri, 10 Jul 2026 12:55:38 +0100 Message-ID: <20260710115546.29644-5-ben.horgan@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260710115546.29644-1-ben.horgan@arm.com> References: <20260710115546.29644-1-ben.horgan@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260710_045603_469632_679479D5 X-CRM114-Status: GOOD ( 11.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The mon_sel_lock is used to protect the mbwu_state, as well as h/w accesses that use MPAMCFG_MON_SEL. However, in mpam_restore_mbwu_state() mbwu_state is accessed without holding the mon_sel_lock. Add the missing locking. Fixes: 41e8a14950e1 ("arm_mpam: Track bandwidth counter state for power management") Signed-off-by: Ben Horgan --- drivers/resctrl/mpam_devices.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index 11b10c3bc334..b34e2a368516 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -1648,16 +1648,24 @@ static int mpam_restore_mbwu_state(void *_ris) u64 val; struct mon_read mwbu_arg; struct mpam_msc_ris *ris = _ris; + struct mpam_msc *msc = ris->vmsc->msc; struct mpam_class *class = ris->vmsc->comp->class; for (i = 0; i < ris->props.num_mbwu_mon; i++) { + if (WARN_ON_ONCE(!mpam_mon_sel_lock(msc))) + return -EIO; + if (ris->mbwu_state[i].enabled) { mwbu_arg.ris = ris; mwbu_arg.ctx = &ris->mbwu_state[i].cfg; mwbu_arg.type = mpam_msmon_choose_counter(class); mwbu_arg.val = &val; + mpam_mon_sel_unlock(msc); + __ris_msmon_read(&mwbu_arg); + } else { + mpam_mon_sel_unlock(msc); } } -- 2.43.0