From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) (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 B462338BDDD for ; Tue, 13 Jan 2026 11:27:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.109.113.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768303648; cv=none; b=sqYPNowIashtyyp3f3ejMLV4zdn7MxeTsMxx/mEzqjCcNWpxH0lIeRwJDch++D6wbDYIrf7OkRJvVpeDm2bNnvAuhcTkJqNULU7ZD+IeclCTZwkGYW/7p2SpaHln3XbD2IdDJQW9IKJEOyi0foFUojvknuvDolFZtVebER6mjJ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768303648; c=relaxed/simple; bh=ABKrTmKWGc8Mf/C0codcgsc89Qahe/+z9sV/efH/NZs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=l8uJdhbUO93b3kAoATdW6t3mSUhenV6mAS6nQLPx6L3BLPaWK9gZ7SnYKltxclBHsx/lBDOcGGysbyIvh0gW0akBCtfZIrgRzQH5ycNOjE1hNXghR0XFk0Tiyq7yP+o1u7Yk5VVHCIPYHApUdMNsaC/pBWfIE0OePlvCIHnktXI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de; spf=pass smtp.mailfrom=alien8.de; dkim=fail (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b=AU0TAYvv reason="signature verification failed"; arc=none smtp.client-ip=65.109.113.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alien8.de Authentication-Results: smtp.subspace.kernel.org; dkim=fail reason="signature verification failed" (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b="AU0TAYvv" Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id A9C8B40E0194; Tue, 13 Jan 2026 11:27:19 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=fail (4096-bit key) reason="fail (body has been altered)" header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 4RvgbsxTzav6; Tue, 13 Jan 2026 11:27:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1768303635; bh=anoHzVr6rs5GmZdIuykufTaKbud4FRKxYCL9R6eB0yo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AU0TAYvvkKSIzkHCMr3cP76XxvSyhO25cKPDia+wJUEi0HVedCfq4IfZEMZpuPoeM IJOB1OD2lPKpCYaP73GymnxTmSTEIkHxpI5/LtnA4HllZrejBInqedDpaTJWZSEBGT cwf8yXm7mhbl0ELMlrdhEcwtwDJqbCwhJYA7TO0U3AkR8uca4EfJ0GR0SWWgETwGnk +xIRa8YmZSf+PfqTzbSXDUn4ZtSfA+JkJSlFjZxC5QEfbvkq1XIh3tYjAmK2/FNKdV uMqghSHanSnP0LsXNJNSbWXxHygVCKtDCDWqhVZACSkRbuKMIWjTbJ16FCJ7zQQc/4 H65K9MB6Nl7mnvf1s5M578u2HpwaSbtF4EwllSDoTAiyn/xwXLaKWt43znSMX3I7XL z39/tyYOJ+iXs0XKf20h7Mg8ckTCYP0zLbOTz+t5SX0W3zBp3jWUfibE32N/uziapd VW4nFkFcgsQwmss7sGMr/0bRu5azppNhVhbaFtM/ldlbClpeZSvrV2at3xWYqqeQ8E kOKsDsiCA28QTWJKLK1n1brDLXZXOzOabystXVPpkeUFv542TuSHPumAxf5S8/C5dz iQLbezeylCbAk1qP6MDY8VgGkSdR/2mqqsxQxMIIfet6Hm01lQyE7MewQnvZm2VA3g PVb0r43rCGxRBtYEpjuX5nzg= Received: from zn.tnic (pd953023b.dip0.t-ipconnect.de [217.83.2.59]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with UTF8SMTPSA id C740740E00DA; Tue, 13 Jan 2026 11:27:02 +0000 (UTC) Date: Tue, 13 Jan 2026 12:27:01 +0100 From: Borislav Petkov To: =?utf-8?B?TWljaGHFgiBDxYJhcGnFhHNraQ==?= Cc: Dave Hansen , Ard Biesheuvel , Thomas Gleixner , Ingo Molnar , Dave Hansen , Chris Li , x86@kernel.org, "H. Peter Anvin" , Dan Williams , Pasha Tatashin , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/1] x86/boot/compressed: Fix avoiding memmap in physical KASLR Message-ID: <20260113112701.GDaWYsBYgLvfcHzyqs@fat_crate.local> References: <20251106162311.2705162-1-mclapinski@google.com> <6074cbfa-b529-45f5-b696-044464ed433e@intel.com> <20251209004338.GAaTdwurZUKZqIqH2_@renoirsky.local> <20260112213929.GEaWVqEdDVwzLbk8Yf@fat_crate.local> 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=utf-8 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable On Tue, Jan 13, 2026 at 12:21:25PM +0100, Micha=C5=82 C=C5=82api=C5=84ski= wrote: > Currently, if you have 4 or fewer memmaps, KASLR correctly avoids > putting the kernel there. That just works now and Ard's change would > disable that. And why do we care about 4 or fewer memmaps? Is that a valid use case whi= ch we have to support? 4 is magic but 5 is a no-no? --=20 Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette