From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 3BB5144A3F1; Fri, 28 Aug 2026 11:54:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787918082; cv=none; b=Hb1TU+0/t8GTKWab95lC3pm91D1ba/bDwnFtlcDrgGCpjE3TRaIPLexU3nMSgEsdnAL5SOikN+4STG5KexNAgWM7ZUWyyG3/zsraNH5LbQ42lID5Wq/UCQ8symwVs0iXWNjVRMBS3ZuLzZHP6r/CDRejtJoFqSDu+RP57ua8tPw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787918082; c=relaxed/simple; bh=/lOeYdMQM0yEpqRm+8VJ/e9jItYU1+vsePznvGbz10E=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Vbg1/YmRuRV48bLfLtv/r+2QE9gi1f0BmrMLrIzlo6CRxNcxEvUF1h4a/vNMaiWrIu8/c1P1FUCi+xrdqj5XF+O+SSLSQmwnu2/BUsjmbqeWbu1XAUUEqaNHlif1KUYsGpkDUGS+gz30lJ+M4yY9DyGTUpZGAZ0yZfS9Dvj47dU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=g5q3o2RC; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass 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="g5q3o2RC" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=/lOeYdMQM0yEpqRm+8VJ/e9jItYU1+vsePznvGbz10E=; b=g5q3o2RCbyi+Yqbp+LTKaPTquE 7gXYHP3tdr0knxX02PNNzCPOBFWn57YdhfVMe2wVBn0jGTz5C70WZiFqi6q+gGpJPkpRmT276v/iI Nx0JCxTzmg7piqalBDEI5CPqK/IwzqOegpNF6bmFCbfFSyS7FPEGTGn4XOICrl7KJogrp6jKLKtiQ BFLUSYdoBlhM6+BShUVl6Sc7u4HOo0ZtjEDUm1F2Mv+GRSw0GDtY23DSYzC52ibhjXBiKIkIMO7OJ m942aboClPHVMssGPyAA7ZQN5VBksW6w6zHJtn0ckV3dbahbmennTJsAMre8Tcbx+K52/+vDwChBY c6XrVZ4w==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzv9w-0000000EdPK-1I3d; Fri, 28 Aug 2026 11:54:12 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 4D3CF30030F; Fri, 28 Aug 2026 13:54:10 +0200 (CEST) Date: Fri, 28 Aug 2026 13:54:10 +0200 From: Peter Zijlstra To: David Stevens Cc: Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Andrew Morton , Dave Chinner , Qi Zheng , Roman Gushchin , Muchun Song , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , Uladzislau Rezki , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Sebastian Andrzej Siewior , Clark Williams , suleiman@google.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-rt-devel@lists.linux.dev Subject: Re: [RFC 06/10] Reclaim memory from blocked kernel stacks Message-ID: <20260828115410.GL687043@noisy.programming.kicks-ass.net> References: <20260827232948.2520558-1-stevensd@google.com> <20260827232948.2520558-7-stevensd@google.com> Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260827232948.2520558-7-stevensd@google.com> On Thu, Aug 27, 2026 at 04:29:44PM -0700, David Stevens wrote: > A new TASK_STACK_RECLAIM state is introduced for tasks that are > blocked waiting for the stacks to be repopulated. Not yet read the full patch, but *why*.