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 D83B2C5B572 for ; Sun, 16 Aug 2026 12:22:42 +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-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Cn0zUN/hrMLQAPmuNzHmIPISGC8g6oolk9qIb89TBIU=; b=Zk/zm1mSSAYDWga+ntxH638SXb 1mAgYcok4jYYrfZIfYF23VqnaZf6yiv/T3kAP8wX3TTDxK/A4ZrIYKB92SLmzV9GaBsIC5Z7o/stt fhwVx5a3MrhrLsX/xZeM15fFI3gS+BMykUWNcOWSYGtUy/XAiDJ2APsgr3oINjH/x5zLmJDHK6XMC lJq4daKOLwCsuROILkPlUxyjKKerXAj/ewhA4wr5apDfvHH0xchVTcLnlILidaBPyG3g1Knk5dkMJ 1lnYBg0eTlxuynf4fmfawDVWtKLYSA3KLp4HMTQH1W6YJvB1Xg51eb1WTaIo55ukzERtBY0E3EMxZ qcbe1vmQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvZss-00000004kMw-1q3T; Sun, 16 Aug 2026 12:22:38 +0000 Received: from mailout1.hostsharing.net ([2a01:37:1000::53df:5fcc:0]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvZsp-00000004kMM-1D3S; Sun, 16 Aug 2026 12:22:37 +0000 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384 client-signature ECDSA (secp384r1) client-digest SHA384) (Client CN "*.hostsharing.net", Issuer "GlobalSign GCC R6 AlphaSSL CA 2025" (verified OK)) by mailout1.hostsharing.net (Postfix) with ESMTPS id 83A3F3BC; Sun, 16 Aug 2026 14:13:37 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 61BAE629CE27; Sun, 16 Aug 2026 14:13:37 +0200 (CEST) Date: Sun, 16 Aug 2026 14:13:37 +0200 From: Lukas Wunner To: Jan Sebastian =?iso-8859-1?Q?G=F6tte?= Cc: Baoquan He , Jan Sebastian =?iso-8859-1?Q?G=F6tte?= , Andrew Morton , Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Dave Young , Catalin Marinas , Will Deacon , David Howells , Jarkko Sakkinen , Jonathan Corbet , Shuah Khan , Paul Moore , James Morris , "Serge E. Hallyn" , Ignat Korchagin , Herbert Xu , "David S. Miller" , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Trond Myklebust , Anna Schumaker , Mimi Zohar , James Bottomley , Marc Dionne , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Eric Biggers , "Theodore Y. Ts'o" , Jaegeuk Kim , Alexander Viro , Christian Brauner , Jan Kara , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , Benjamin Marzinski , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, keyrings@vger.kernel.org, linux-doc@vger.kernel.org, linux-security-module@vger.kernel.org, linux-crypto@vger.kernel.org, linux-nvme@lists.infradead.org, linux-nfs@vger.kernel.org, linux-integrity@vger.kernel.org, linux-afs@lists.infradead.org, netdev@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, dm-devel@lists.linux.dev Subject: Re: [PATCH v2 01/13] kexec: add CRASH_WIPE_SECRETS to wipe secrets before kdump Message-ID: References: <20260811-crash-zeroize-rework-v2-0-9561d13c2340@jaseg.de> <20260811-crash-zeroize-rework-v2-1-9561d13c2340@jaseg.de> <9765f7ea-36bb-4c7b-a19b-7facec97b762@jaseg.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9765f7ea-36bb-4c7b-a19b-7facec97b762@jaseg.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260816_052235_500105_9765C755 X-CRM114-Status: GOOD ( 14.44 ) 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 Wed, Aug 12, 2026 at 12:08:39PM +0200, Jan Sebastian Götte wrote: > I can imagine one alternative way to approach this, tell me what you think: > Instead of registering wipe handlers that memzero places on panic, I could > put an optional registry of (addr, len) descriptors into crashkernel memory > that the original kernel populates with the PAs of buffers to clear ahead of > time. Then the kdump kernel could do the actual memzero. This would remove > all code from the actual kdump path here. The registry could be made > per-core to avoid locks. Or create a dedicated mempool from which all sensitive data is allocated, then call mempool_free_bulk() on kexec to poison everything in that pool? Thanks, Lukas