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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93477C3DA7D for ; Sat, 31 Dec 2022 13:42:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230430AbiLaNlE (ORCPT ); Sat, 31 Dec 2022 08:41:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229484AbiLaNlC (ORCPT ); Sat, 31 Dec 2022 08:41:02 -0500 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2B902E9 for ; Sat, 31 Dec 2022 05:41:01 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 4F1041EC0493; Sat, 31 Dec 2022 14:41:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1672494060; 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: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=m7rCTpk9c3/hvAowOtgf/iURb5jKAxrFcYb/Bg6gYRQ=; b=Tjc0FU6RHjhOvvCJfJrEuEBEOAExLE5buF0lpG62t4mKcXRx7eZHjNH6zMgr4zuhVmlB+3 HQkg3c3WFNG6YBQ17h7XTBLpD0yE3yfWEWpHL/7tl3cQtaMdI7McVw7GcdBNba16CYno0d NxAQ+L/Vk4LcN4m0LEUuo4cp93aDJJI= Date: Sat, 31 Dec 2022 14:40:59 +0100 From: Borislav Petkov To: "H. Peter Anvin" Cc: "Jason A. Donenfeld" , pbonzini@redhat.com, ebiggers@kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, ardb@kernel.org, kraxel@redhat.com, philmd@linaro.org Subject: Re: [PATCH qemu] x86: don't let decompressed kernel image clobber setup_data Message-ID: References: <46466e54-25c3-3194-8546-a57cd4a80d9d@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <46466e54-25c3-3194-8546-a57cd4a80d9d@zytor.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 30, 2022 at 05:06:55PM -0800, H. Peter Anvin wrote: > This needs to be something like: > > kernel_add_identity_map(sd_addr, sd_addr + sizeof(*sd)); > kernel_add_identity_map(sd_addr + sizeof(*sd), > sd_addr + sizeof(*sd) + sd->len); It still #PFs with that: (gdb) bt #0 0xffffffff84738576 in native_halt () at ./arch/x86/include/asm/irqflags.h:57 #1 halt () at ./arch/x86/include/asm/irqflags.h:98 #2 early_fixup_exception (regs=regs@entry=0xffffffff84007dc8, trapnr=trapnr@entry=14) at arch/x86/mm/extable.c:340 #3 0xffffffff846ff465 in do_early_exception (regs=0xffffffff84007dc8, trapnr=14) at arch/x86/kernel/head64.c:424 #4 0xffffffff846ff14f in early_idt_handler_common () at arch/x86/kernel/head_64.S:483 #5 0xc149f9894908788d in ?? () #6 0xffffffffff2003fc in ?? () #7 0x0000000000000010 in fixed_percpu_data () #8 0xdffffc0000000000 in ?? () #9 0xffffffff84007ea8 in init_thread_union () #10 0xffffffffff20088d in ?? () #11 0x0000000000000000 in ?? () /me goes to dig more. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette