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 5F7DB22A80D for ; Wed, 18 Mar 2026 22:16:39 +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=1773872201; cv=none; b=hAbSDUY9eU5su8aaizuHSpbXZcnwYiEGdmaYv9XJw/tk/gTQpYB914mR3lSNO5KywpY+OaOYB7p3/Cz9ozuJdGVLnYmJBWo5FJAcl2fw4ry1M73FmtRwU4AqfusFaJ/Y1KK9crkcpXZvWVY486QUkZV6Jla/ZhqD78GdRxdgBHA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773872201; c=relaxed/simple; bh=XndpB0N1n8kkakT9mHbv0/n1UilLVAfqRJx2qDmBeQI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oYe9IC8ULGS0k1xj3ee6rHjqlbxy/3UbTYljvQmgky3fgHRtpq5dW5IMwIPMganj1M61mJEYn6N1b3zIHARYp7mSiZ/wJ2FvZXju8y10UGZv7ac/zzLHk+VYY8tlwJcTtzLc7/cFj8xUgoEhJMyXAVl/K7Hycxzy367hdhyJ1Dw= 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=H9yQrLRi; 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="H9yQrLRi" 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=XeLQmoWthRFakA1mlpKpNVtnQKskgbO8SZKvZdIChho=; b=H9yQrLRi+MOB76/JBukM12C5qG h/F336a0czoBk7eDDeC3LSU3tjmflv7ufE2Kq2uBjLkJTzOrjUERhQpdGIfyVKBoCARKWF738QohL jz0cdSPd4wSsIx+toPufOu0FB2UT1F6b2bkTpuiQEGDwVwhUYdDM4Y2xAgX2HQ8gvBbz/MtFWhETb JIqcWtLuCuTe5iQM/woupL07PisywEWS9FAeA4/to22TyXyv6R25QKaKavpB8LfIkGX/coV0i9sqP qu31Qr8Zpxl29onCRZMQ0V6QLYgi6U4S6mGph89zS4UzYJnkiMfjxndjFpb+2nRUGRrTriMDHQrPw jirAHB+w==; Received: from 2001-1c00-8d85-5700-266e-96ff-fe07-7dcc.cable.dynamic.v6.ziggo.nl ([2001:1c00:8d85:5700:266e:96ff:fe07:7dcc] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2zBi-0000000CLJR-2IA9; Wed, 18 Mar 2026 22:16:27 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B2B96302FFB; Wed, 18 Mar 2026 23:10:34 +0100 (CET) Date: Wed, 18 Mar 2026 23:10:34 +0100 From: Peter Zijlstra To: Thomas Gleixner Cc: Florian Weimer , LKML , Mathieu Desnoyers , =?iso-8859-1?Q?Andr=E9?= Almeida , Sebastian Andrzej Siewior , Carlos O'Donell , Rich Felker , Torvald Riegel , Darren Hart , Ingo Molnar , Davidlohr Bueso , Arnd Bergmann , "Liam R . Howlett" Subject: Re: [patch 8/8] x86/vdso: Implement __vdso_futex_robust_try_unlock() Message-ID: <20260318221034.GQ3738010@noisy.programming.kicks-ass.net> References: <20260316162316.356674433@kernel.org> <20260316164951.484640267@kernel.org> <87ecliokzz.ffs@tglx> <87zf46m6j1.ffs@tglx> <87fr5wn63p.ffs@tglx> 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: <87fr5wn63p.ffs@tglx> On Wed, Mar 18, 2026 at 11:08:26PM +0100, Thomas Gleixner wrote: > On Tue, Mar 17 2026 at 23:32, Thomas Gleixner wrote: > > On Tue, Mar 17 2026 at 11:37, Florian Weimer wrote: > > Something like the below compiled but untested delta diff which includes > > also the other unrelated feedback fixups? > > The more I look into it, the more I regret that we allowed mixed mode in > the first place. Which way I turn it around the code becomes more > horrible than it really should be. > > If I understand it correctly then the only real world use case is the > x86 emulator for ARM64. That made me think about possible options to > keep the insanity restricted. > > 1) Delegate the problem to the ARM64 people :) > > 2) Make that mixed size mode depend on a config option > > 3) Require that such a use case issues a prctl to switch into that > special case mode. > > or a combination of those. > > Andre? Well, he has this patch set that creates multiple lists, which would nicely solve things for FEX I recon.