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 A9E1228726A; Mon, 24 Nov 2025 14:49:28 +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=1763995770; cv=none; b=bgZgQ1J7JxAkD2mpAmsOGXMVqmjSy6njZPFPV+GObOq5pkSho6ABeynv+V80KTLgDbs9ttLxidPEfo3wxYHrfd9sFPv83MwJ66gGpVbr6AAyJd7mIVpxK0NkSadHiqIIZ9Qw+0n89fkYvBYaZTYzTjhlpEbss6l+ZRsG4klNs1A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763995770; c=relaxed/simple; bh=eYVozzDJl+VlYa+0Xgx12ibrXMDoIH+H55EfKIIHcFU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=IUiugDvXoyqE3UKOO2cFyFptliCXZMgrIXt8ZVxnOZTtxlyjnGF7Vz5hvDRmaVMM8oV4TZXJUBbNaL0Dss/Vo5DOHym3WdE+ctUmBojs3EqnD8fkWwBJw8niC1SGVcGz4vcCqEiQlUxdVM6GAsGBsQQTe+4usnhiWb0AuRo8WdE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (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=TzKctMUe; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (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="TzKctMUe" 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=T6qo3JM9edKF9yotTrqC4KSWMlApaFYSQyRMCU7A0QQ=; b=TzKctMUePuak9AjKx6VCue/cUf NGK3H/RvKt7isPtkb8XB163+z/iiJ28CRVy1LxLAqSONdk0XyC4/2jadqhXmJ8ExM6Y10IcKePMDb nDi9cMY3LdUjnPrc32RaCOaMOeBkXrjGCWkzywRBpqhLnRJkscEWbZUqwGL7MkUUlNB/Cz6TJCtGL 4ZwbXiKaAhZOMbrr3xoo2UPDUVfQZxSNtJN/Zg8la2nnYw/SjWQpRFehAc/g+owRbIiQemlCwlRTW FUftrTTwZPlLFZHRRYC+dS1wBy7VmZOdtOJojQB+vi/fw3+IVJYvfE7XwL3amum/RzF4lZuJxSuJk dp/f/e/A==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vNX0y-00000003u95-2jhQ; Mon, 24 Nov 2025 13:54:00 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 84766300230; Mon, 24 Nov 2025 15:49:23 +0100 (CET) Date: Mon, 24 Nov 2025 15:49:23 +0100 From: Peter Zijlstra To: Boqun Feng Cc: Stephen Rothwell , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Linux Kernel Mailing List , Linux Next Mailing List , ojeda@kernel.org, Danilo Krummrich , Alexandre Courbot , nouveau@lists.freedesktop.org, Alice Ryhl Subject: Re: linux-next: build failure after merge of the tip tree Message-ID: <20251124144923.GK4068168@noisy.programming.kicks-ass.net> References: <20251124231644.38d0303b@canb.auug.org.au> <20251124123249.GP4067720@noisy.programming.kicks-ass.net> <20251124144714.GT3245006@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-next@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: <20251124144714.GT3245006@noisy.programming.kicks-ass.net> On Mon, Nov 24, 2025 at 03:47:14PM +0100, Peter Zijlstra wrote: > On Mon, Nov 24, 2025 at 06:00:52AM -0800, Boqun Feng wrote: > > On Mon, Nov 24, 2025 at 01:32:49PM +0100, Peter Zijlstra wrote: > > > On Mon, Nov 24, 2025 at 11:16:44PM +1100, Stephen Rothwell wrote: > > > > Hi all, > > > > > > > > After merging the tip tree, today's linux-next build (x86_64 allmodconfig) > > > > failed like this: > > > > > > > > ERROR: modpost: "NULL" [drivers/gpu/nova-core/nova_core.ko] undefined! > > > > > > > > > > Rust :/ > > > > > > So I have: > > > > > > $ make O=tmp-build LLVM=-22 allmodconfig > > > $ make O=tmp-build LLVM=-22 rustavailable > > > Rust is available! > > > $ grep -e CONFIG_RUST= -e CONFIG_NOVA= tmp-build/.config > > > $ > > > > > > Help ?!? > > > > > > > [CC nova] > > > > On my system it seems that RANDSTRUCT=y prevents the enabling of RUST, > > but I'm sure Danilo and Alexandre have better ideas about how to enable > > nova-core. > > Ah, indeed, RANDSTRUCT seems to be messing things up. I tried disabling > that, but then I need to manually enable random crap to get Nova happy > and menuconfig isn't very nice. > > I really don't think rustavailable is doing a good job here. Strictly > speaking yes, its available, but figuring out why things don't work is a > giant pain in the arse. > > Now, lets see if frobbing Kconfig to disqualify RANDSTRUCT will let > allmodconfig work better. This... ok now lets see wtf the actual problem is. diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening index 86f8768c63d4..4a5890796ac2 100644 --- a/security/Kconfig.hardening +++ b/security/Kconfig.hardening @@ -282,6 +282,7 @@ config CC_HAS_RANDSTRUCT # Randstruct was first added in Clang 15, but it isn't safe to use until # Clang 16 due to https://github.com/llvm/llvm-project/issues/60349 depends on !CC_IS_CLANG || CLANG_VERSION >= 160000 + depends on BROKEN choice prompt "Randomize layout of sensitive kernel structures"