From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) (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 31D0C28D8CA; Fri, 13 Jun 2025 23:20:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749856852; cv=none; b=mGZ2/bCK68iRVYfAc/OFsS+ksXOHQZRv2BczG28I8wZ3/Xy2sCREBtnazds7Miy3klV/g9kYRU7/UAC/JqgzYXjrN5qpADl7EgbFJE6+VwwB8S2VH4cLVngQMJDwh4Sf5arBo8psnXHRg45bP/mAp38UJ/wX5C6bMDnO9IEm810= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749856852; c=relaxed/simple; bh=DQPacqRFq47t4t1mV2H6DBnnyvNPrh7szv6ag9li9Nk=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Tv3yJL8kYpB7VfcowH8SRH3Hxkwev7+Bc6KkfOOOHnQmOlyyBWh2weolXK627TyVzyo3hxzhyVjrefqThIoAjvFAH9f+rnV9SF5g6+KeL4AuTL21i/NCXOMvqVuOefCVFQvE1LXlJxWteZaEqp6qBpix76dFHC2mMitocYL672Q= 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=drSQKrh8; arc=none smtp.client-ip=198.175.65.10 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="drSQKrh8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1749856850; x=1781392850; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=DQPacqRFq47t4t1mV2H6DBnnyvNPrh7szv6ag9li9Nk=; b=drSQKrh8eAkiTvL7Rt5SC8/3EhJDztI7w80WNe57FTpzVqomJv3vZWju lNmQ49BT78ZbjQDdKoJKdQh9PLji8hzwBeDetEYIz5197b9UHOiHp0z+b NYGRmuaZMKxqGRa/4l7/fk+qiYgb4XSFK/oUfYeEavAwWHp56UHW7/kbH 03ntG96naNxMlKUY7iN8rqVlwaZtZEHK7ZdRz1kxaBrLUOikfSsrCaeF1 mWuZLFWS1hL/bTsoqM/yayOTrKlhuRfErdKxlyyL9GmpinLcUpxlpwrUS rW0vFuNzAPr0gIWfLPTC97a05Ejywz8SS3wTDdVcLy/g1JIDKR+Db2Vpw w==; X-CSE-ConnectionGUID: FIhbxJyZRqiz9fxYoUBeBg== X-CSE-MsgGUID: KsAF46G2SCqqmSudv1FtiA== X-IronPort-AV: E=McAfee;i="6800,10657,11463"; a="69524360" X-IronPort-AV: E=Sophos;i="6.16,235,1744095600"; d="scan'208";a="69524360" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jun 2025 16:20:50 -0700 X-CSE-ConnectionGUID: CMo9xzuVSAe6vQIZ/paMhg== X-CSE-MsgGUID: rpd3kJhgQDe0Q5mg2fQqxA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,235,1744095600"; d="scan'208";a="147788027" Received: from mgoodin-mobl3.amr.corp.intel.com (HELO vcostago-mobl3) ([10.124.222.194]) by orviesa006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jun 2025 16:20:49 -0700 From: Vinicius Costa Gomes To: Yi Sun , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Cc: yi.sun@intel.com, gordon.jin@intel.com Subject: Re: [PATCH v2 2/2] dmaengine: idxd: Fix refcount underflow on module unload In-Reply-To: <20250607130616.514984-3-yi.sun@intel.com> References: <20250607130616.514984-1-yi.sun@intel.com> <20250607130616.514984-3-yi.sun@intel.com> Date: Fri, 13 Jun 2025 16:20:48 -0700 Message-ID: <87h60j8bzj.fsf@intel.com> Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Yi Sun writes: > A recent refactor introduced a misplaced put_device() call, leading to a > reference count underflow during module unload. > > There is no need to add additional put_device() calls for idxd groups, > engines, or workqueues. Although commit a409e919ca3 claims:"Note, this > also fixes the missing put_device() for idxd groups, engines, and wqs." > It appears no such omission existed. The required cleanup is already > handled by the call chain: > idxd_unregister_devices() -> device_unregister() -> put_device() > > Extend idxd_cleanup() to perform the necessary cleanup, and remove > idxd_cleanup_internals() which was not originally part of the driver > unload path and introduced unintended reference count underflow. > > Fixes: a409e919ca32 ("dmaengine: idxd: Refactor remove call with idxd_cleanup() helper") > Signed-off-by: Yi Sun > > diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c > index 504aca0fd597..a5eabeb6a8bd 100644 > --- a/drivers/dma/idxd/init.c > +++ b/drivers/dma/idxd/init.c > @@ -1321,7 +1321,12 @@ static void idxd_remove(struct pci_dev *pdev) > device_unregister(idxd_confdev(idxd)); > idxd_shutdown(pdev); > idxd_device_remove_debugfs(idxd); > - idxd_cleanup(idxd); > + perfmon_pmu_remove(idxd); > + idxd_cleanup_interrupts(idxd); > + if (device_pasid_enabled(idxd)) > + idxd_disable_system_pasid(idxd); > + if (device_user_pasid_enabled(idxd)) > + idxd_disable_sva(idxd->pdev); idxd_disable_sva() got removed in commit 853b01b5efd7 ("dmaengine: idxd: Remove unnecessary IOMMU_DEV_FEAT_IOPF") > pci_iounmap(pdev, idxd->reg_base); > put_device(idxd_confdev(idxd)); > pci_disable_device(pdev); > -- > 2.43.0 > Cheers, -- Vinicius