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charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1668037719; a=rsa-sha256; cv=pass; b=C0oKrVlSDpb1AB+5UIy1/EQn7P/8ZTewwG6vHIyGiAaR0umPvjaSuNO3YcoCGoPkb2r/7d llJ/VwRYech9xgKEphi8f9hT3qoCIrmyJAMtpu2h4jNkjZ2AiZLSa66Dm6nyGNrO6yOMu4 ME5tz0NhziwOrkUVGcUmRrWDdJk1uB0= ARC-Authentication-Results: i=2; imf05.hostedemail.com; dkim=pass header.d=iki.fi header.s=meesny header.b=auWrSkoE; spf=pass (imf05.hostedemail.com: domain of aaro.koskinen@iki.fi designates 195.140.195.201 as permitted sender) smtp.mailfrom=aaro.koskinen@iki.fi; dmarc=none; arc=pass ("iki.fi:s=meesny:i=1") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668037719; 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=qJTJOn9jstyUEzsYgJ/tqc7eioOfTr+ik31YpBBRsgk=; b=AbUMSpe4sfSfVgLwF03Ocr/09E7Z/eSCGCVBJBNEwdK/vkjSVL3Xag1tw30f3Jkugd/oSR 0RodHnsrH97kvgiU9fSuipn8osO+lwrInmTCwyC8f+bxiuE4zwSqPHCR5uOXLJrX5iyl+P w7WVs3kSrXWCGRNZLNFL7R8V9rtynZo= X-Stat-Signature: gh6q7mjjuzuk9ao7sf9jazcwcp4pjn6x X-Rspam-User: Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=iki.fi header.s=meesny header.b=auWrSkoE; spf=pass (imf05.hostedemail.com: domain of aaro.koskinen@iki.fi designates 195.140.195.201 as permitted sender) smtp.mailfrom=aaro.koskinen@iki.fi; dmarc=none; arc=pass ("iki.fi:s=meesny:i=1") X-Rspamd-Queue-Id: A20C7100004 X-Rspamd-Server: rspam09 X-HE-Tag: 1668037718-2595 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: Hi, 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 failing early when there is a bug. See e.g. commit 120ee599b5bf ("staging: octeon-usb: prevent memory corruption") A.