From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793661733; b=j021EGf7C0R8YBTzCqChNA7goyxSlv8crrDdVErbTbpsQSPLiMtP52xY22TCfObKFMUy eb8yekFkXIhEJvuViY4Xp7AkNVOadwyzN7sqCRgYHq3lpzZ1DMPMlJvgIGFOWdC0sH598 sBVu8gMCqmyjmKjmztrts94KC7tlgmeoaRGxfYt7GABSXmKvAMMCgfYE2JzzA1a31L7KQ qyM7hi3D55W2aw//z5dw4vaDlh8CBayZhWfl/SZcJKmIrDwe9Hw9dtv9KDxFFl3VDh1+R 0uXzjoDXbs1Y2qR95cqonTniQClReCQexq+HIFL6D5yqjG/mKZ/HB65WyfGJodNABMg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793661733; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=EJntW4sE1R6awD6CuX5OdObbrbfpjinSguufJYZ7kd0=; b=3jBb6nHfa9j0fvqZ6DumCFvpZq4a/xYsdYwx3iSfsXTpKiXSfmujyDJOIb2HKRFxKlum hI/hTokwqUsa4ouKqHQw9blEZi1w8HiMiVmTL0TfK5OWSZBUp2iJXnm+CocVwtOJKj1sy RkOuK7VX9KWn05KVgG/BT/svzXIDsuashYegOTtmzhhJ4cBFpa/HqiahxdiMcXNSKoTJY Xi31Fug/Pg2j46VM7a6D28NNPTDhtqt+TeCii3B7aiKW45IbDfgTnVdcA3Vv+nEgpXAPx 5HCurGmuMNpOucC799vak9Mqnj9tqxb6B4Kjra0c9qu5G2JdwRbWC9n4TV8BKaxxgPA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Q0VbvgTf; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED52C606A324 for ; Mon, 2 Nov 2026 23:22:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Q0VbvgTf Received: by smtp.kernel.org (Postfix) with ESMTPSA id 694FA1F00A16; Mon, 2 Nov 2026 23:22:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793661732; bh=EJntW4sE1R6awD6CuX5OdObbrbfpjinSguufJYZ7kd0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Q0VbvgTflBkPM/Xx1miqafD8w2akw0j3k26HUa7o7dncUSYlwiYfq1lO+LA9CezzH hjBjq1Ti7oonLpa5tFgFY0XeI34X29XGmaXtQXWjE/VVr/cAfXiUKLRT6j+ufkOG5N 8nuHhrRz9Yqh1he4c8Ko6yQQt6zy3W+2OQW5UTWQNIrhJYxkLO/w1XFsnOcmYSCQtq wIzWV4vj2tNg4EHN3gr/LZOCn9jFJOh8rrQy1+v4my2Rp0cL2gQ3tzr/Baq0bmjlY3 EkopYPwEBsVtxxNs2xtw5G0iNm6tUeD+ZZr8SrU8qxL2m247uGHReFt9SA293jWpDi 9sNq+jZQboMnw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v9 4/8] serial: 8250_omap: quiesce DMA IRQ handling before shutdown Reply-To: sashiko-reviews@lists.linux.dev To: "James Hilliard" Cc: linux-serial@vger.kernel.org In-Reply-To: <20261102-submit-serial-8250-dma-cancel-v1-v9-4-9159caade148@gmail.com> References: <20261102-submit-serial-8250-dma-cancel-v1-v9-0-9159caade148@gmail.com> <20261102-submit-serial-8250-dma-cancel-v1-v9-4-9159caade148@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 02 Nov 2026 23:22:12 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > disable_irq_nosync() masks the UART interrupt without waiting for a > running handler. That handler can have observed up->dma and continue > using it while shutdown releases the DMA channels and clears the pointer. > Synchronizing the IRQ later in serial core does not protect those accesse= s. >=20 > Publish the DMA shutdown gate under the port lock before the final RX > flush and interrupt masking. Have DMA IRQ handling check the same gate > under the lock, so a queued interrupt cannot restart receive processing > after the final flush. >=20 > Drain the UART IRQ outside the port lock before releasing DMA state. > The lock excludes competing RX processing during the flush, while > disable_irq() also waits for a handler that observed up->dma before > acquiring the lock. >=20 > Fixes: fef4f600319e ("serial: 8250: omap: Fix life cycle issues for inter= rupt handlers") > Signed-off-by: James Hilliard Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-submit-ser= ial-8250-dma-cancel-v1-v9-0-9159caade148@gmail.com?part=3D4