From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.14]) (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 3B59F44F568; Thu, 1 Oct 2026 18:18:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790878711; cv=none; b=Exp6FmDL4k6CwvO9HQrjnrgGzAJZYDmTmjkyCKrsocIIVuotzgWE034GhhRcnWmLj/1fW+k1d8GNrflaoLWTy0KqVPcAVvufRpYIKdlfwWnwTxgUVPO0NaoL/hB5qaSRLf9Ct8LZMMamwgTxKznU++Hd6NXL0FXd7FOx279wicI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790878711; c=relaxed/simple; bh=IabwWKOswkpFd4HIBeDWnWJYOXJ4bYdDLIUepUooG3I=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pBi9i0XH5C6DThJ+5aqLNKhfx3EoqCxPnNoIl2NS9d9brBoyUEPOkRKtfejGt8/LHlMYOAmbDCzzVWvkMn6dwGpqyZyFStMEeODV11VQuCpWngAacb3rmwvuK2AaU7Ip5tmriimqNeKWpyDGd0yXKNBOngNKNlEG8Tmr3PTu1K8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=eVcd9hq4; arc=none smtp.client-ip=192.198.163.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="eVcd9hq4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790878707; x=1822414707; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=IabwWKOswkpFd4HIBeDWnWJYOXJ4bYdDLIUepUooG3I=; b=eVcd9hq47Ywurow9nlD0AiThzOlmRD51svtalwSaW/Kt5PUOOEdf0+lU CouHQmjRyrs/Zm3A0T1F8/z6OGpVHSHIOJLC3yymZCxfZyXOwMWe5U14J Sa1Oh2csa25VghZlUe5L4BH8bd9nlYHMLw4ldW9JBlldrzO+Grj6gU1R0 nZ0hlehfSLaQsjokM3oCFpvIfx6PpZq3RbElHMo1VGlGiBafYi4R5Ffxn nks3VnoCq6GBD7iSgcJOJs8RV+U85e00IBEabvxgOMe1+2fWTUpEAxhnf y0jOl/fdS0YMiRW893ynfM9uMZH1nv7OgfwixzK0SvmeSVVtl2NFz/GCb A==; X-CSE-ConnectionGUID: v++a9cwiSR+Iu3zZ+dCU1A== X-CSE-MsgGUID: xR4ugUJLQRykPESE8e0tcQ== X-IronPort-AV: E=McAfee;i="6800,10657,11922"; a="91665421" X-IronPort-AV: E=Sophos;i="6.27,135,1787036400"; d="scan'208";a="91665421" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by fmvoesa108.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2026 11:18:22 -0700 X-CSE-ConnectionGUID: v7RVLPY1SgGF+8A6XIEwiA== X-CSE-MsgGUID: 790NtqA+S6KlwPhAmiBeKQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,135,1787036400"; d="scan'208";a="305557716" Received: from abityuts-desk1.ger.corp.intel.com (HELO localhost) ([10.245.244.27]) by orviesa002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2026 11:18:21 -0700 Date: Thu, 1 Oct 2026 21:18:18 +0300 From: Andy Shevchenko To: Imre Kaloz Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linux-usb@vger.kernel.org, Greg Kroah-Hartman , stable@vger.kernel.org Subject: Re: [PATCH] PCI: Disable MSI for ULi M1575 EHCI controller Message-ID: References: <20260930191100.6127-1-kaloz@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260930191100.6127-1-kaloz@kernel.org> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Wed, Sep 30, 2026 at 09:10:58PM +0200, Imre Kaloz wrote: > With MSI, the ULi M1575 EHCI controller (10b9:5239) intermittently stops > executing its asynchronous schedule. Control transfers time out ("device > not accepting address", "device descriptor read/64"), the port is handed > to the companion OHCI controller and the device ends up at full speed. On > a configured hub the stall shows up as hub descriptor and status read > failures. Only re-initializing the controller recovers it. > > On a Sun Ultra 45, 65 of 800 controller initializations stalled with MSI > and none of 200 with INTx. Each initialization is an unbind and bind of > ehci-pci on the EHCI function, with MSI or INTx selected through its > msi_bus attribute; with this quirk, 0 of 100 cycles of the same loop > stalled. The stall reproduces on a kernel that already contains > commit 0b60557230ad ("usb: ehci: Prevent missed ehci interrupts with > edge-triggered MSI"). > > The OHCI functions (10b9:5237) keep MSI. They showed no stall, and the > hub enumerated through them on MSI during the EHCI failures, so only the > EHCI function is quirked. > > The illumos EHCI driver also disables MSI on this chip, in > ehci_register_intrs_and_init_mutex() in > usr/src/uts/common/io/usb/hcd/ehci/ehci_util.c. > > Until USB HCDs started trying MSI first in v5.9, the controller always > used INTx. Disable MSI so it uses INTx again on this chipset. Since it's tested on real HW, the quirk makes sense. Thanks for report and the fix! Reviewed-by: Andy Shevchenko -- With Best Regards, Andy Shevchenko