From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0DB47C5B552 for ; Mon, 9 Jun 2025 23:18:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ijZeolarUTtqmy4GxxtNrTYwrNFMDVmIVcgrPMPb5JU=; b=KuSp7kMmlDRuRS55wUlaLoS5fD l1KBTfMtd3+J0aBH96eBbA+agcImrNCWEB6GkPWunmgLAsrKE9xxHlxO88qpIXBdd0jk6+/2uyKOZ zkk8F1mZHTdDOLP5HfQSATJEpw04waDjcUXbU6pQyfsMvsOvp45UKdGHsOkMzm6K54HLzss2QYTW8 bPNcEq5XCiDnJ6hzorr0ErTxvgTsad/yqqy616tFt/RO2S9XbBmGIDVyGSU19bBVhMagVocX5S5xI /KCOLRbkHDTUvOsM9HLoUlcsnm8oj8pYvb+i+8UZQpBYyNYUZZXfbZLzqg/a4PeO94OALFbflMCDG 26xS3/kQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uOlkq-00000005Qjd-0Wnm; Mon, 09 Jun 2025 23:18:12 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uOlkn-00000005Qj9-1Eve for kexec@lists.infradead.org; Mon, 09 Jun 2025 23:18:10 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1749511086; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ijZeolarUTtqmy4GxxtNrTYwrNFMDVmIVcgrPMPb5JU=; b=T0hzl6Ym3KWKTHpKN/bpbFCWffoq+CX05qv+AUEFDSMELQ18DNgYH6goAxsSi9FwJXJPmW MGRUu70Uj4lvPuyw11x5lg+2tC0ZfEsFPFt1zuYftrKYhgWdU6KWD7PEkaA89ITKsTNEDw mHysBKBdvZD+Gg0vwHgDqMb54ms9e60= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-439-l06piRltPdW19Y3G1SVI6g-1; Mon, 09 Jun 2025 19:18:03 -0400 X-MC-Unique: l06piRltPdW19Y3G1SVI6g-1 X-Mimecast-MFC-AGG-ID: l06piRltPdW19Y3G1SVI6g_1749511082 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (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) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E686A19560AD; Mon, 9 Jun 2025 23:18:01 +0000 (UTC) Received: from localhost (unknown [10.72.112.181]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 84FDF19560A3; Mon, 9 Jun 2025 23:17:59 +0000 (UTC) Date: Tue, 10 Jun 2025 07:17:55 +0800 From: Baoquan He To: Alexander Graf , Andrew Morton Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Pasha Tatashin , nh-open-source@amazon.com, Zhongkun He , Bcc: bhe@redhat.com; Subject: Re: [PATCH v4] kexec: Enable CMA based contiguous allocation Message-ID: References: <20250521152934.48841-1-graf@amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250609_161809_411464_4C1CE0C4 X-CRM114-Status: GOOD ( 15.36 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 06/09/25 at 09:03am, Alexander Graf wrote: > > On 21.05.25 17:29, Alexander Graf wrote: ...... > > Using CMA allocations has two advantages: > > > > 1) Faster by 4-50 ms per 100 MiB. There is no more need to copy in the > > hot phase. > > 2) More robust. Even if by accident some page is still in use for DMA, > > the new kernel image will be safe from that access because it resides > > in a memory region that is considered allocated in the old kernel and > > has a chance to reinitialize that component. > > > > Signed-off-by: Alexander Graf > > > Ping? Not seeing this patch in Linus' master tree :) I saw Andrew had added this to his mm-nonmem-unstable, it could be dropped later because of new version posting. I would like to ACK this patch, let's see how it's going. One thing is if IOMMU is on, the devices of no .shutdown method could still be on flight and look up the IO page table and corrupt kernel, that's another story. Acked-by: Baoquan He