From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 8F919157469 for ; Thu, 1 Aug 2024 08:54:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722502494; cv=none; b=RwadJ2mAgIlE1D6puMrkyj5hZS36Mb0Kcb1kX8lsAa9dGYy+2GMhtb7Jzyq2XetNNfXlcO6mKo1TCHzZPazcDWMFzVsB4Mz4OWXadZZLEBhW7LzCYqstn9hFQviQcNgdrmgAZdOIZI6kLNn6LdwIhKgMoWjpPtOXC/ntwQqgtts= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722502494; c=relaxed/simple; bh=ELV8yhQ3TxrJXNL7GNabK8kZ9yHlPm2Vud4wYk8Bk2A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=FtPXNrmc7cAbGU4jiSQ2sBCIIO7Cc5+8C2339pI1DUihhQ4xCBlbsUn6MjVrACvQdg+vh2OhT9bObGDYzGDwnAAM13GOrYIj0HZfVPpWjrjTrM8TbLJnnRyrpnW/KZnEN1LjlglE9J27978MjlXtDqg+MM5gMX2Lhi8ExF1ixgs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=N5zaQu2B; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="N5zaQu2B" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=xRMLmj9qlDqy9loOkVGrrbLQIpp1pJzJMWgVhDvT3VA=; b=N5zaQu2BTClhZyvu1Q1xMWnrHU W394OdHVO4mens/WLCTFtnYvWKOJFHtPSZXREX5ij1a8w28OgrRH2cok/QDWONE3agmOIUHq73pMb LVDmXaggGRDNQeIncVjCH+Iz82Te7qU1Vb+Q04pXZJTN3m0+AhJArlS5ZdD6W3gZ+DFlJjOc3X4YR JmzVo1r4c5WVQbExhS+NIZ0G+S93XYUwHYYrv1ae9mpUmK2vkyOdoPHH176Gyu6tRjTvci1EHsQ9l W2VXADEj78TbGkGvGi5+n/k1qlgkLVX/eJlLBc+AdKUgmoF0yr8svZfkEvA9ZeHJMVVYtV1wy8FP7 sKZp3G4w==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZRaD-00000005Pu9-2mCc; Thu, 01 Aug 2024 08:54:50 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 4FA1E30074E; Thu, 1 Aug 2024 10:54:49 +0200 (CEST) Date: Thu, 1 Aug 2024 10:54:49 +0200 From: Peter Zijlstra To: Guenter Roeck Cc: Thomas Gleixner , Linus Torvalds , Jens Axboe , Andy Lutomirski , Ingo Molnar , Peter Anvin , Linux Kernel Mailing List , the arch/x86 maintainers Subject: Re: Linux 6.11-rc1 Message-ID: <20240801085449.GM33588@noisy.programming.kicks-ass.net> References: <20240731122002.GE33588@noisy.programming.kicks-ass.net> <87mslx67dm.ffs@tglx> <20240731155551.GF33588@noisy.programming.kicks-ass.net> <20240731163105.GG33588@noisy.programming.kicks-ass.net> <20240731165108.GH33588@noisy.programming.kicks-ass.net> <87bk2d5v83.ffs@tglx> <20240731212007.GW26599@noisy.programming.kicks-ass.net> 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=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 31, 2024 at 03:22:53PM -0700, Guenter Roeck wrote: > On 7/31/24 14:20, Peter Zijlstra wrote: > > On Wed, Jul 31, 2024 at 07:26:04PM +0200, Thomas Gleixner wrote: > > > On Wed, Jul 31 2024 at 18:51, Peter Zijlstra wrote: > > > > On Wed, Jul 31, 2024 at 06:31:05PM +0200, Peter Zijlstra wrote: > > > > Thomas, this all still relies on the full text section being PMD mapped, > > > > and since we don't have ALIGN_ENTRY_TEXT_END and _etext has PAGE_SIZE > > > > alignment, can't have a PAGE mapped tail which then doesn't get cloned? > > > > > > > > Do we want to make pto_clone_entry_text() use PTI_LEVEL_KERNEL_IMAGE > > > > such that it will clone whatever it has? > > > > > > Yes, I think so. > > > > The alternative is ripping that level thing out entirely, and simply > > duplicate anything we find in the page-tables. > > > > The patch below (on top of the previous one, because otherwise it doesn't > apply) causes qemu to bail out hard, with > > ... > [ 3.658327] sr 2:0:0:0: Attached scsi generic sg0 type 5 > [ 3.858040] sched_clock: Marking stable (3834034034, 23728553)->(3865222956, -7460369) > [ 3.861469] registered taskstats version 1 > [ 3.861584] Loading compiled-in X.509 certificates > [ 4.082031] Btrfs loaded, zoned=no, fsverity=no > [ 4.096034] cryptomgr_test (69) used greatest stack depth: 6136 bytes left > > No backtrace or other message, it just exits immediately. Ha, I hadn't even compiled the thing :-) I was just wondering alound and in patch form if the whole level thing was worth having in the first place. If it lives, I'll make sure to test it. Thanks!