From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from s3.sipsolutions.net ([2a01:4f8:191:4433::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n4pnz-00CfC8-3h for linux-um@lists.infradead.org; Tue, 04 Jan 2022 19:49:12 +0000 Message-ID: <41fe09354fc736fb1ff2cb429e035633f24176ce.camel@sipsolutions.net> Subject: Re: Occasional hung with UM after enable VMAP_STACK From: Johannes Berg Date: Tue, 04 Jan 2022 20:49:05 +0100 In-Reply-To: <8c26a869-0cbe-a38c-8a8d-9f3f171f7e72@collabora.com> References: <8c26a869-0cbe-a38c-8a8d-9f3f171f7e72@collabora.com> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Walter Lozano , linux-um@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Sjoerd Simons , ritesh sarraf On Tue, 2022-01-04 at 16:26 -0300, Walter Lozano wrote: > > Thank you for your quick response. The Debian configuration on package > user-mode-linux have these settings > > CONFIG_HAVE_ARCH_VMAP_STACK=y > CONFIG_VMAP_STACK=y OK, so it actually _is_ enabled. > as you can see in [1]. I did run some tests disabling those settings, > which passed without any hung. > > Unfortunately the "occasional" behavior makes this issue a bit tricky to > debug. > Right. Hm. I've been running our tests with it for about three months and haven't observed any hangs, but I guess that doesn't mean much. To be honest, I have no particular reason to even want it, other than that it catches accidental DMA from stack more easily ... so I guess if we can't find anything, we might as well revert it. Feels like it _should_ work though, since it's just a different location for the stack. johannes _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um