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 E03AB3D9544; Thu, 20 Aug 2026 09:10:21 +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=1787217024; cv=none; b=D7bKb4yMl2nVy7kCqsTbv7MVhiFQ/DLSOswXS3TxAE+Le5CwwmF6M3Rldcu4cZVxAVCmpLlxOn8cTr9q1l5s+emcJ4AvIaAXwceg4RcGufIGVqr+8grYtO4JPdhOVkIS5yGH/3+B3YGPkOrEVafdpKsRaGYpr3bzh5TdltbVmOs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787217024; c=relaxed/simple; bh=EqfKLhU//OFBs6OTvjbqed9nlF1pEprwancPXtG4OxI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=o88C9VGPRUfxFNlJhvEccJ+Nln8M0fnrStH/WxyN/2arLzevza9k5jnrDMCe1nMHWRysTZz5abwbAuauJLLh4uBufw4m6YizYADkkWMIM8i0d3YpNIO5fgr3yFtHwuWKnqrhvgEgY+lhXkJLHBQyxQAuBAYFO79OP0NoDfMB2+U= 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=hJjO9+4F; 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="hJjO9+4F" 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=5dBVRnhidfoLU0S8715OX6iAUkqOyaPiamhb8ngMZXI=; b=hJjO9+4FjNWbEBh6E58MJ+kxOQ YF6bvl0T6o6Pp5MW6vxfCpjHHYYIX8/gOKzUKNeW7P8u6yEV3isiT7f7QsjtDdgHWHNxl3uwFa0eL MrvF5Z8cTdJAr9OL9zwkjgcJKlgxnrIOeLMxUvH6Nvvvwv+Q6NTcNdN6ssFPyZnNa2PsWV9SCuGkW OX7GzMLlSNDmXAT43ySSvc8/eXJpAD1kCh1L8ZXJ73Spq8NrDnb51+JBhqet0JCj+wIbQyWb45jSt EsYQsKFJUbH1lRowE+nD20TGykfyD+IBq1q6LHEhF3b4+QpoqCbNd0WKVuVbh9RnvUVNxIXc4t/Og OJhxaKGA==; 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 1wwymx-0000000FEuL-1rph; Thu, 20 Aug 2026 09:10:19 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id E2309301BDE; Thu, 20 Aug 2026 11:10:18 +0200 (CEST) Date: Thu, 20 Aug 2026 11:10:18 +0200 From: Peter Zijlstra To: Sergey Senozhatsky Cc: Miklos Szeredi , fuse-devel@lists.linux.dev, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v2] fuse: permit freezing while waiting for request answer Message-ID: <20260820091018.GA4120091@noisy.programming.kicks-ass.net> References: <20260819023542.561653-1-senozhatsky@chromium.org> <20260820084933.GA4036497@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: fuse-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: On Thu, Aug 20, 2026 at 06:07:18PM +0900, Sergey Senozhatsky wrote: > On (26/08/20 10:49), Peter Zijlstra wrote: > > Message-ID: <20260820084933.GA4036497@noisy.programming.kicks-ass.net> > > > > On Wed, Aug 19, 2026 at 12:03:32PM +0200, Miklos Szeredi wrote: > > > Why is this unsafe exactly? Does that unsafeness apply to > > > filesystems? If so why do we allow freezing while blocked on > > > sb_start_write()? > > > > Getting frozen with lock A held, while another task is blocked on A in > > an unfreezable state results in the system not being freezable. > > Right, but then the system says "suspend failed" (tasks refuse to freeze > after 20sec) and just thaws everything back in? People don't like suspend failing. People like to close their lid, throw laptop in bag, and expect laptop to not cook itself to death.