From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 27A3C3FB7EF; Fri, 8 May 2026 15:21:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778253718; cv=none; b=NMDveR3OE3hpZo2o2w3GIBTaFzDVHL42t0zqT17JC6suPpqmPWZPykahNKqNrwG9xWhU9tBiNmA+VdEtVD5yblmtEVZBGe4nDRyMWNE3xTnDUWbm4rC19l6mdF0RtX0QfxE7jYK3lYK9GvtWMLJ7mBH9V+FeZ/ai26BudU9RIyI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778253718; c=relaxed/simple; bh=1Ts4kYseduboKsIUf+lbfxpxNyozd7l4VzIGUhH5GtA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OTWFAGYSemuR6b/eCYjhY+C8u/G/tpQvdxilgp40D6hxSUGLVIP7pRWqSgECmup4QJMRQWGI6lz+Y7tmFBtj46AhP9ZWINaVcPA6DAF2odSaU7rEUGseHVzOvQdk9Ih4/AsoeV1fZmfyXqLMqftD2pLU3+lwS8VKNhG2SKcVAIQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RMuxdTE4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="RMuxdTE4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AD1FC2BCB0; Fri, 8 May 2026 15:21:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778253717; bh=1Ts4kYseduboKsIUf+lbfxpxNyozd7l4VzIGUhH5GtA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RMuxdTE4WdGdY6Ms3G75+5Sd9Tz5kXTHmCAaeFF0rc8SarwZ518vkkKQvKxRCghL6 IfPkgpWWQZT9JrkkB96zVRVHyPUY3/PgCXNJoPWZMsGqvZQ4StDzboAaxQdW9/J2TQ z9DBrjpW4suhPA+lRu5CSJFgXGstEDuWf0teBuKk= Date: Fri, 8 May 2026 17:21:55 +0200 From: Greg KH To: "Ionut Nechita (Wind River)" Cc: ilpo.jarvinen@linux.intel.com, stable@vger.kernel.org, linux-serial@vger.kernel.org, andriy.shevchenko@linux.intel.com, chris.friesen@windriver.com Subject: Re: [REQUEST] Backport 8250_dw BUSY deassert series to 6.12.y stable Message-ID: <2026050837-criteria-occupant-c6ec@gregkh> References: <20260508151614.498810-1-ionut.nechita@windriver.com> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260508151614.498810-1-ionut.nechita@windriver.com> On Fri, May 08, 2026 at 06:16:14PM +0300, Ionut Nechita (Wind River) wrote: > From: Ionut Nechita > > Hi Ilpo, Greg, > > We're running kernel 6.12 (LTS) on production systems with DesignWare > 8250 UARTs and are hitting the BUSY assertion issue that your recent > series addresses in 6.18: > > Ilpo Järvinen (7): > serial: 8250: Protect LCR write in shutdown > serial: 8250_dw: Avoid unnecessary LCR writes > serial: 8250: Add serial8250_handle_irq_locked() > serial: 8250_dw: Rework dw8250_handle_irq() locking and IIR handling > serial: 8250_dw: Rework IIR_NO_INT handling to stop interrupt storm > serial: 8250: Add late synchronize_irq() to shutdown to handle DW UART BUSY > serial: 8250_dw: Ensure BUSY is deasserted > > Patch 7/7 has Cc: stable, but it depends on patches 1-6 for the new > infrastructure (serial8250_handle_irq_locked(), the reworked locking in > dw8250_handle_irq(), etc.). > > Could the full series be nominated for 6.12.y stable backport? Or if > that's too invasive for stable, could you advise on the minimal subset > that would allow patch 7 to apply cleanly on 6.12? Why not just move to 6.18.y instead if you have this issue? thanks, greg k-h