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 405CF19F464 for ; Tue, 15 Jul 2025 23:14:28 +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=1752621269; cv=none; b=KPYcG5nKrM80+hfafVesiblDfSRvB7aDYw29AmrNp0Roosy10FViIRhQhHjU5m8n3juU+NYWSknGba55M0X4dvQBs9fRKAyqBUeqV9ldTEkPBj05c84AnT+Md0Io2qlv0uu5yyDd5AzWET6i+yjLJ757511ViJ8w6RtovMZMsC8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752621269; c=relaxed/simple; bh=rfBtyqXY8rhywUkEMeVOyTnMFXFkjdOjRkkh6U0nA9Y=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Pzdt8g2G+NoC3y7FWyb2/AzyPoQx6l8M0FuYcpd3oACsp4N394eBYkEh/6kXXys0NJs+3E/RzHB+2cFh2YGDDkschZraOhywHY4rPW6zAA9xYykWDJbI/SzwS6ETKKd61dqbKBXvaNR1ryn2zgHYUMboqrNphwerkoFXBOMvgxA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YQ0U49Ad; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YQ0U49Ad" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2D17C4CEE3; Tue, 15 Jul 2025 23:14:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752621268; bh=rfBtyqXY8rhywUkEMeVOyTnMFXFkjdOjRkkh6U0nA9Y=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=YQ0U49AdhwuiL+X7IAQjAQibQKS2AGzVMrJwmq4TSZ4Zi0aKDgYzD4vHRhLmgPjNZ 8dMz7DD+C+cJPkzA+m/ZO782kZ9s2IE9mCobDNndNC7tlyNgqzYHjJFFVNXcv/sviD gHuT4s1i1eCE/RK6eJBldvQ3VsJ86TxCuawBUDVfzyx5WQlKHY9nzbJeM2WJ+vNENN DOicIUMX/OjIGzDrKkoxSWDW3IhF1Hjd42eR+K9qMwpA00NoDzfhGYbkpvWnBhfHSk rUdXmErFAkTGKo46kY8GYXQFZrjNBKL92Ktn+5INf2M2DzaWEQBvzUTjKPja2DBYO9 UXES9geIEUmag== Message-ID: <9a825e2c-7183-4c1e-afae-a8c55e27a70e@kernel.org> Date: Wed, 16 Jul 2025 08:14:26 +0900 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] nvmet: pci-epf: Do not complete commands twice if nvmet_req_init() fails To: Rick Wertenbroek Cc: rick.wertenbroek@heig-vd.ch, alberto.dassatti@heig-vd.ch, Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org References: <20250715091826.3970789-1-rick.wertenbroek@gmail.com> Content-Language: en-US From: Damien Le Moal Organization: Western Digital Research In-Reply-To: <20250715091826.3970789-1-rick.wertenbroek@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/15/25 18:18, Rick Wertenbroek wrote: > Have nvmet_req_init() and req->execute() complete failed commands. > > Description of the problem: > nvmet_req_init() calls __nvmet_req_complete() internally upon failure, > e.g., unsupported opcode, which calls the "queue_response" callback, > this results in nvmet_pci_epf_queue_response() being called, which will > call nvmet_pci_epf_complete_iod() if data_len is 0 or if dma_dir is > different than DMA_TO_DEVICE. This results in a double completion as > nvmet_pci_epf_exec_iod_work() also calls nvmet_pci_epf_complete_iod() > when nvmet_req_init() fails. > > Steps to reproduce: > On the host send a command with an unsupported opcode with nvme-cli, > For example the admin command "security receive" > $ sudo nvme security-recv /dev/nvme0n1 -n1 -x4096 > > This triggers a double completion as nvmet_req_init() fails and > nvmet_pci_epf_queue_response() is called, here iod->dma_dir is still > in the default state of "DMA_NONE" as set by default in > nvmet_pci_epf_alloc_iod(), so nvmet_pci_epf_complete_iod() is called. > Because nvmet_req_init() failed nvmet_pci_epf_complete_iod() is also > called in nvmet_pci_epf_exec_iod_work() leading to a doubple completion. > > This patch lets nvmet_req_init() and req->execute() complete all failed > commands, and removes the double completion case in > nvmet_pci_epf_exec_iod_work() therefore fixing the edge cases where > double completions occurred. > > Signed-off-by: Rick Wertenbroek > --- > drivers/nvme/target/pci-epf.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c > index a4295a5b8d28..aad828eb72d6 100644 > --- a/drivers/nvme/target/pci-epf.c > +++ b/drivers/nvme/target/pci-epf.c > @@ -1243,7 +1243,7 @@ static void nvmet_pci_epf_queue_response(struct nvmet_req *req) > iod->status = le16_to_cpu(req->cqe->status) >> 1; > > /* If we have no data to transfer, directly complete the command. */ Maybe change this comment to: /* * If the command failed or we have no data to transfer, complete * the command immediately. */ Other than this, this looks good, so feel free to add: Reviewed-by: Damien Le Moal > - if (!iod->data_len || iod->dma_dir != DMA_TO_DEVICE) { > + if (iod->status || !iod->data_len || iod->dma_dir != DMA_TO_DEVICE) { > nvmet_pci_epf_complete_iod(iod); > return; > } > @@ -1604,8 +1604,13 @@ static void nvmet_pci_epf_exec_iod_work(struct work_struct *work) > goto complete; > } > > + /* > + * If nvmet_req_init() fails (e.g., unsupported opcode) it will call > + * __nvmet_req_complete() internally which will call > + * nvmet_pci_epf_queue_response() and will complete the command directly. > + */ > if (!nvmet_req_init(req, &iod->sq->nvme_sq, &nvmet_pci_epf_fabrics_ops)) > - goto complete; > + return; > > iod->data_len = nvmet_req_transfer_len(req); > if (iod->data_len) { > @@ -1643,10 +1648,11 @@ static void nvmet_pci_epf_exec_iod_work(struct work_struct *work) > > wait_for_completion(&iod->done); > > - if (iod->status == NVME_SC_SUCCESS) { > - WARN_ON_ONCE(!iod->data_len || iod->dma_dir != DMA_TO_DEVICE); > - nvmet_pci_epf_transfer_iod_data(iod); > - } > + if (iod->status != NVME_SC_SUCCESS) > + return; > + > + WARN_ON_ONCE(!iod->data_len || iod->dma_dir != DMA_TO_DEVICE); > + nvmet_pci_epf_transfer_iod_data(iod); > > complete: > nvmet_pci_epf_complete_iod(iod); -- Damien Le Moal Western Digital Research