From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout1.hostsharing.net (mailout1.hostsharing.net [83.223.95.204]) (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 EC41F345EBA; Sun, 16 Aug 2026 12:13:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=83.223.95.204 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786882422; cv=none; b=h3iBtymWi5Gi8xRJgqXmkfztozOp909+iSDnhDwmEpXu2Z3YKak+08v2PpB+sEVpbONmYrsGouy7cKmqwKv4Dq4ZwB/6FpSPj/9s9W10tKbQjnXO//shprXHvD0xDmgWQupEp8vuekJhIMEoUF8s2EXLENHbJ3zh/BKltaEJUqg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786882422; c=relaxed/simple; bh=Cn0zUN/hrMLQAPmuNzHmIPISGC8g6oolk9qIb89TBIU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AtSoVFvUMKEZZI0ZBhQHE3Vwz8fvfHH9N0T+t2d9mJtRxxSeppHD8m0x13vIRDfxgPvOSkjwpzdiSFl8BWU4xFSiYho3PCRuOH7UxHegFCXBGgHOE1VKYBd/h4dMJHKXqM4yTlkqlGchj0t7qpIwX8aJ2s1nXt1+dYlNjl9TouU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de; spf=pass smtp.mailfrom=wunner.de; arc=none smtp.client-ip=83.223.95.204 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=wunner.de 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 91A983BD; 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> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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> 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