From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.yourmailgateway.de (relay.yourmailgateway.de [46.38.247.119]) (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 30E1141D215; Fri, 24 Jul 2026 10:21:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.38.247.119 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784888505; cv=none; b=Ai2oYUHUikQS7YZf+FldHoZF4xY1Ew+napx5csRCUlLORDu1TwvC0RtriYbFJRM6Kkrh8YfSdySejHnfBTEZTD2bD1C3QjjFEr1l3c8MVT+i7HBHfSqCICXj1bnjwOmbdsHbEFasAKXZGiNIXQjwIQVyR/ozyz8MHz5E9qdFfuI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784888505; c=relaxed/simple; bh=o1i6BGbHsXA2S1cnmSyWtCQB/tcY7gOoTS0f9ZPd+gw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Dx93C9dcitEh4mCMyRhTYeNPlPrO8BvPnHt75mbi7m4ROhXpiTMoOjfadDPQTYB/o8LFXw+x1z8DWaLgUQuHh3+s4tjPE8qRm1P/OI/V7N4OWKVdnkOmohs2Us5Mv32AHbG60aYENbaloD0/FbOYBImedllXysp/AzGAwvRJhTs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=leemhuis.info; spf=pass smtp.mailfrom=leemhuis.info; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b=OhU8R58Q; arc=none smtp.client-ip=46.38.247.119 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b="OhU8R58Q" Received: from mors-relay-8404.netcup.net (localhost [127.0.0.1]) by mors-relay-8404.netcup.net (Postfix) with ESMTPS id 4h63tj5HkRz8L7H; Fri, 24 Jul 2026 12:21:33 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=leemhuis.info; s=key2; t=1784888493; bh=o1i6BGbHsXA2S1cnmSyWtCQB/tcY7gOoTS0f9ZPd+gw=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=OhU8R58QE2v8FnEHmf0IhAkFnRUuHit96VHskuy0c3JPF1BGKgCXqzPr2+mRaGFrW 25ztoWyqndgjKpnp8dZOfBnZ7RLHAWpwD40klhqzrmQNymveo2M3PEH7GmUPm/J0pI hcJeQIaWflrRB5MPwxYKbL/DVvZDX4MljnWrEN1DnjnKuem3XavSdGp3bPp7DRLS3+ XtvpCCPpXUt+B2RV4ShIi0UVyvkgPl54eVp/jBAyzng+0qiUKVpiMCmrdzvO0J4brH APWAqi+TQHpdM25cnoQ1jkxKabAVocNi6TH4dhWefm5syPRvKW9TGdkskDAEIXP0hl aOPyBDTylUrAA== Received: from policy02-mors.netcup.net (unknown [46.38.225.35]) by mors-relay-8404.netcup.net (Postfix) with ESMTPS id 4h63tj4Wrsz4xJK; Fri, 24 Jul 2026 12:21:33 +0200 (CEST) Received: from mxe9fb.netcup.net (unknown [10.243.12.53]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by policy02-mors.netcup.net (Postfix) with ESMTPS id 4h63tg5329z8tH7; Fri, 24 Jul 2026 12:21:31 +0200 (CEST) Received: from [IPV6:2a02:8108:8984:1d00:a0cf:1912:4be:477f] (unknown [IPv6:2a02:8108:8984:1d00:a0cf:1912:4be:477f]) by mxe9fb.netcup.net (Postfix) with ESMTPSA id 666925F9DB; Fri, 24 Jul 2026 12:21:30 +0200 (CEST) Authentication-Results: mxe9fb; spf=pass (sender IP is 2a02:8108:8984:1d00:a0cf:1912:4be:477f) smtp.mailfrom=regressions@leemhuis.info smtp.helo=[IPV6:2a02:8108:8984:1d00:a0cf:1912:4be:477f] Received-SPF: pass (mxe9fb: connection is authenticated) Message-ID: Date: Fri, 24 Jul 2026 12:21:29 +0200 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 v5 00/10] block,md,nvme: correct handling of unsupported P2PDMA transfers To: Mykola Marzhan , Kiran Kumar Modukuri , Chaitanya Kulkarni , Jens Axboe Cc: Li Nan , Xiao Ni , Song Liu , linux-block@vger.kernel.org, Christoph Hellwig , linux-nvme@lists.infradead.org, Guoqing Jiang , linux-raid@vger.kernel.org, Leon Romanovsky , Jason Gunthorpe , Logan Gunthorpe , Bjorn Helgaas , Shivaji Kant , Pranjal Shrivastava , Henrique Carvalho , stable@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-pci@vger.kernel.org, Sagi Grimberg , Yu Kuai , Keith Busch , Linux kernel regressions list References: <20260723204206.76930-1-mykola@meshstor.io> From: Thorsten Leemhuis Content-Language: de-DE, en-US In-Reply-To: <20260723204206.76930-1-mykola@meshstor.io> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-PPP-Message-ID: <178488849128.3023183.9483321544575683507@mxe9fb.netcup.net> X-NC-CID: bgfn6WwD6tNqsJl92qX4PPcCQ3rLaKDwr3eppdgdbpQWarfWVJI= On 7/23/26 22:41, Mykola Marzhan wrote: > md treats an unsupported P2PDMA transfer to a member as success, and > nvme-rdma retries one forever. Whether peer memory can be DMA-mapped > depends on the PCIe topology between the two devices, and since v6.17 > the failure completes as BLK_STS_INVAL: retryable for multipath and > deliberately ignored by md for member failures, so mirrors silently > diverge. > [...] > Routing: patch 1 block, 2-8 md, 9-10 nvme; 7, 8 and 10 use the new > status. Patch 1 alone stops the divergence and the dm-multipath > requeue loop; the nvme-rdma loop also needs 9-10; everything else > refines the fallout, so the series bisects safely. The md patches > fix a v7.2-rc1 regression (02666132403a), except 3 (older bug, > stable) and 5 (refactor). This landed on my radar due to the word "regression" here. Given the complexity of this patch-set and that we are at v5 please allow me to ask: Should 02666132403aec ("md: propagate BLK_FEAT_PCI_P2PDMA from member devices to RAID device") [v7.2-rc1] maybe be removed for now and reapplied later once this was sorted out? Or is that for some reason unneeded? Note, no need for a long explanation needed in the latter case, a brief statement from long-term developer will suffice. Ciao, Thorsten