From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 008.lax.mailroute.net (008.lax.mailroute.net [199.89.1.11]) (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 3BD93EEC5 for ; Thu, 2 Jan 2025 03:46:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735789612; cv=none; b=LD6L5aSwklksWeW2I14pUTCTtHqvCgUB4UgURXBu0t2PoQOdTxsNa4jCG3VThqnaR/eXwQxp1WzCbb2cmgGG7PEOWpRcUxkP1Z+sBS+bo8QHCCDTiQNNjZnc05De9v7fk6bx5WuWKsmwjMduPSDMtE/MsiPwCQgwCD6P3k02R68= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735789612; c=relaxed/simple; bh=CZpro6u7cYh9vS+AVFakwjJwYA9Pl3znlDwHsHoZRtg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=QqzzNPHTmCSh7X3ngi7K4Pj0C5M6mgd4OO0RrlyCKtvhJyL4u+1Va2wWBWSq/kbanqThDk3SYNZcXK0RA+uyUJMMVxt+volK10ZLKVoPbE+F8wdOtKqIQL1okMKC706wR3rOU1qBnAtgw86fnrPg/fEeDdmjgunzGg/IEWACEnE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=sl0gvAaM; arc=none smtp.client-ip=199.89.1.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="sl0gvAaM" Received: from localhost (localhost [127.0.0.1]) by 008.lax.mailroute.net (Postfix) with ESMTP id 4YNt1Q46B4z6ClbJB; Thu, 2 Jan 2025 03:46:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1735789607; x=1738381608; bh=IMZCg6UPNbSEgc7QJXczqauE kiHtn8uXZwp1gFILWi0=; b=sl0gvAaMLu843TOlwHX3xxHOcya2VhPE2DAAgTOT Lin6/4Qhc5JuUNIqfQEQ62LpATb2+dxpW+ntWW6HV3mlHckCpbB0N2D77/h+w0So HbAR/6XE0qBhJGOG11fQ8y9OJml3OB98ahGWwoF5SjTB6+RrPyH5kKPfO6f1fiuP aq9GTrgAtl6GaCd1ZWuvnv9FPgmRhli1fGKgvK/DVkVSDk8NHD5pP2+ZURq09KHI TE/9uMB2mNcn3M1eJfDcVUIUZxvdS45PHSoadxxRgIbfD1P/4UqgltiDZw8VXbTT n5Z4g7OmEHSbTU157ljoVso2nuiCOjlJAHvssj+PUOs5Yg== X-Virus-Scanned: by MailRoute Received: from 008.lax.mailroute.net ([127.0.0.1]) by localhost (008.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id rvy0heKzexPN; Thu, 2 Jan 2025 03:46:47 +0000 (UTC) Received: from [192.168.3.219] (c-73-231-117-72.hsd1.ca.comcast.net [73.231.117.72]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 008.lax.mailroute.net (Postfix) with ESMTPSA id 4YNt1J2Wt6z6ClbJ9; Thu, 2 Jan 2025 03:46:43 +0000 (UTC) Message-ID: <0b34bfc9-2cd3-40a8-8153-3207a6d62f8c@acm.org> Date: Wed, 1 Jan 2025 19:46:41 -0800 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] block: make queue limits workable in case of 64K PAGE_SIZE To: Ming Lei Cc: Jens Axboe , linux-block@vger.kernel.org, Yi Zhang , Luis Chamberlain , John Garry , Christoph Hellwig References: <20250102015620.500754-1-ming.lei@redhat.com> <0b423229-f928-4210-9351-dca353071231@acm.org> Content-Language: en-US From: Bart Van Assche In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/1/25 6:49 PM, Ming Lei wrote: > On Wed, Jan 01, 2025 at 06:30:30PM -0800, Bart Van Assche wrote: >> Additionally, this patch looks wrong to me. There are good reasons why the >> block layer requires that the DMA segment size is at least as large >> as the page size. > > Do you think 512byte sector can't be DMAed? A clarification: I was referring to the maximum DMA segment size. The 512 byte number in your email refers to the actual DMA transfer size. My statement does not apply to the actual DMA transfer size. >> You may want to take a look at this rejected patch series: >> Bart Van Assche, "PATCH v6 0/8] Support limits below the page size", >> June 2023 (https://lore.kernel.org/linux-block/20230612203314.17820-1-bvanassche@acm.org/). > > '502 Bad Gateway' is returned for the above link. That link works fine here on multiple devices (laptop, workstation, smartphone) so please check your setup. Thanks, Bart.