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charset=us-ascii Content-Disposition: inline In-Reply-To: <20221109234832.GE307514@darkstar.musicnaut.iki.fi> ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1668037884; a=rsa-sha256; cv=pass; b=vq8Q1/itNEGeuWRPrbGJIYjXzXMkBo+WVGQlIuH+84Epj7FBXeCjXvFGkGkn7wtK/9erPx Mh7Zy3a8bqvokJhPYPqbqSA9Mg5XJdubkxb6/dJONKybTELxCklfro4WiIFijIPawVFVGU JhAxaunem4Z2VhTa7Ke/x9E6aoOzV/o= ARC-Authentication-Results: i=2; imf29.hostedemail.com; dkim=pass header.d=iki.fi header.s=lahtoruutu header.b="R5/i0NbI"; arc=pass ("iki.fi:s=lahtoruutu:i=1"); spf=pass (imf29.hostedemail.com: domain of aaro.koskinen@iki.fi designates 185.185.170.37 as permitted sender) smtp.mailfrom=aaro.koskinen@iki.fi; dmarc=none ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668037884; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=rTBJWXlCBEfCiw4GBwY4/JZJS0qKN69t0qMTsAB6HnM=; b=TZs4xIReTC2jCS1EXd+hWXEljbdZbAH3TV2wEME/+w40Vevck989NSX6HYPQ248fmkOAAp MAtGcRIC5pznv5Z0Z9dM6QKlpXrfvnEpyF3H2aFmYuEPFSTO28r08ggDK/yOPDyqkKuhFH ZcI1EAuol3QfnSEophgOxbcnbA9WalY= X-Stat-Signature: hri1fobgxk3xg1aizsnsf6p5r8m4fdnt X-Rspamd-Queue-Id: 0C171120007 Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=iki.fi header.s=lahtoruutu header.b="R5/i0NbI"; arc=pass ("iki.fi:s=lahtoruutu:i=1"); spf=pass (imf29.hostedemail.com: domain of aaro.koskinen@iki.fi designates 185.185.170.37 as permitted sender) smtp.mailfrom=aaro.koskinen@iki.fi; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1668037883-230610 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Nov 10, 2022 at 01:48:35AM +0200, Aaro Koskinen wrote: > On Wed, Nov 09, 2022 at 01:39:12PM -0800, Linus Torvalds wrote: > > On Wed, Nov 9, 2022 at 12:56 PM Paul Cercueil wrote: > > > > > > It worked fine on some boards, but on others it had about a 25% chance > > > of booting, and 75% chance of hanging at boot. I tried printk-debugging > > > it, and was coming to the conclusion that it's memory corruption of > > > some sort. > > > > > > Then I switched to SLUB and all the problems are gone. Same with SLAB. > > > > > > So while I can't say for sure that SLOB is broken (it might be > > > triggering a bug somewhere else), I am highly suspicious that it is. > > > > I have this distinct memory of having seen other reports like this, > > but my google-fu is not strong enough to back that up. > > > > There definitely has been recurring noise about SLOB issues. There's a > > reason people have wanted to remove it for years and years. > > Some of the reported SLOB issues have been actually real driver bugs, > that go unnoticed when SLUB/SLAB are used (unless perhaps debug stuff > is enabled). I'm not saying kernel should keep SLUB, but it's good at ^^^^ SLOB, sorry for a typo. > failing early when there is a bug. See e.g. commit 120ee599b5bf ("staging: > octeon-usb: prevent memory corruption") > > A.