From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fhigh6-smtp.messagingengine.com (fhigh6-smtp.messagingengine.com [103.168.172.157]) (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 27001364BC; Wed, 7 Aug 2024 15:43:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=103.168.172.157 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723045395; cv=none; b=kD03oO+wUCPP+otgqJfy3OE1nWZWql9DbeTj8uTAR27cL8YPMJZkL//AJF4buf/aIJdTBMamtK0WdMsFpYJjdGVeQzQ9UjTLxiSUFwWhi8S8+SZE/CCuOGcCnomXNp6OZeEGoN6sP53GZMYGaF8karOMzR55c6x6wW/YlXBKQKE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723045395; c=relaxed/simple; bh=++TeG6EHfEJD65UKnaVWPlbeLkN+PdeGteBNaUB37sU=; h=MIME-Version:Date:From:To:Cc:Message-Id:In-Reply-To:References: Subject:Content-Type; b=cFTXeKhe9if77dV8La5ckS7WbWDZReG1VNLQNDzBGJ85ijJTL7aHZIBoPwNq5YYKb0/b+7bCVbX86CqpKYTYjnaZDkyP7OKzGcjobGxGJP0j4yVXZbr2LcKW2/N4tlq+3NfnwSLqc0q1vEby2s7+utekU7uXDfO8wXJlVWGqalE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arndb.de; spf=pass smtp.mailfrom=arndb.de; dkim=pass (2048-bit key) header.d=arndb.de header.i=@arndb.de header.b=bxeYvS+X; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=exKmP3jz; arc=none smtp.client-ip=103.168.172.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arndb.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arndb.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arndb.de header.i=@arndb.de header.b="bxeYvS+X"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="exKmP3jz" Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailfhigh.nyi.internal (Postfix) with ESMTP id 49219114EA9D; Wed, 7 Aug 2024 11:43:13 -0400 (EDT) Received: from imap51 ([10.202.2.101]) by compute4.internal (MEProxy); Wed, 07 Aug 2024 11:43:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm2; t=1723045393; x=1723131793; bh=GmXLkrFZAsugNyP57xRFNgv2S9AFoG7Hpwkv4yw8wuw=; b= bxeYvS+XLKJTyVoWC4GwjqSI2peT76zGkI3b3SJ4cMozO6eCo90ZA7GW3bVwxkKd Q1Vct9AxPjzBO40EJXzJ2MJP7rkg6K68kvFOExNjG9aMZhdtU8X70JBqDS8pAa+4 ZeCJjxV3PAucqqcIOXOdyptNb75t6T0MchTrUgWr92Tmd3DSJ1DFcg7K/wyNHVXi 1UUJvgtG/Vnpn7elYuomTCkN79F7a072cncoggwMUdi22/80fHqy3Hr0FCqThbnv XCFPB2s+OoumFeqe6FF+3g8Z/7FjUhHUsGhobriwQG/y2PXXeGYyUfDkd2zld2EG WO43NRhMLukCpkS98MUqZA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; t=1723045393; x= 1723131793; bh=GmXLkrFZAsugNyP57xRFNgv2S9AFoG7Hpwkv4yw8wuw=; b=e xKmP3jzjwzEi3xr+5dJ/nKvhdnUCgs5trLyhS3cR+Dp2Pl50lHMn3NsY288gZ7e8 wLpMoUOjaG1yA1ej09ITc4MtLzU7Di8idxng2MiTLiyep43Vap+1zr8aVq6WT4Jx nKg0vWti10jMPZR24kTqcqalFYyXZe8cwhGF4595BMfZxX4rI7DnlHoFTtOfYUWF TNUYv8aS2KbFqQ9SfcyRUVJht4sn9S6di1ue+SuZWgSWenMjHvNcNo4KbUUlw3bc fewP+uxyLPyq+OqOd2PN2kd0pVDuLxjjfn/KCjsUTeJ6A2JPlNUbWqOe3gm05cDm cE4Du7WX90fT21RIJ3ZXw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeftddrledtgdelvdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefoggffhffvvefkjghfufgtgfesthejredtredttdenucfhrhhomhepfdetrhhn ugcuuegvrhhgmhgrnhhnfdcuoegrrhhnugesrghrnhgusgdruggvqeenucggtffrrghtth gvrhhnpefhtdfhvddtfeehudekteeggffghfejgeegteefgffgvedugeduveelvdekhfdv ieenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegrrh hnugesrghrnhgusgdruggvpdhnsggprhgtphhtthhopedt X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 75F3DB6008F; Wed, 7 Aug 2024 11:43:12 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Wed, 07 Aug 2024 17:42:03 +0200 From: "Arnd Bergmann" To: "Stewart Hildebrand" , "Bjorn Helgaas" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , "H. Peter Anvin" , "Michael Ellerman" , "Nicholas Piggin" , "Christophe Leroy" , "Naveen N. Rao" , "Thomas Zimmermann" , "Sam Ravnborg" , "Yongji Xie" , =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= , "Philipp Stanner" Cc: x86@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Message-Id: <877b71ea-341b-4013-bbee-8f4df9c961c9@app.fastmail.com> In-Reply-To: <20240807151723.613742-1-stewart.hildebrand@amd.com> References: <20240807151723.613742-1-stewart.hildebrand@amd.com> Subject: Re: [PATCH v3 0/8] PCI: Align small BARs Content-Type: text/plain Content-Transfer-Encoding: 7bit On Wed, Aug 7, 2024, at 17:17, Stewart Hildebrand wrote: > In this context, "small" is defined as max(SZ_4K, PAGE_SIZE). > > This series sets the default minimum resource alignment to > max(SZ_4K, PAGE_SIZE) for memory BARs. In preparation, it makes an > optimization and addresses some corner cases observed when reallocating > BARs. I consider the prepapatory patches to be prerequisites to changing > the default BAR alignment. It's probably worth noting that Linux does not support any architectures with software page sizes smaller than 4KB, and it would likely break a lot of assumptions, so max(SZ_4K, PAGE_SIZE) is really the same as PAGE_SIZE in practice. Arnd