From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4525CC74A42 for ; Thu, 11 Jul 2019 07:24:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A53420838 for ; Thu, 11 Jul 2019 07:24:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728205AbfGKHY1 (ORCPT ); Thu, 11 Jul 2019 03:24:27 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:40329 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725963AbfGKHY0 (ORCPT ); Thu, 11 Jul 2019 03:24:26 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id E503580617; Thu, 11 Jul 2019 09:24:12 +0200 (CEST) Date: Thu, 11 Jul 2019 09:24:23 +0200 From: Pavel Machek To: Al Viro Cc: Andrew Morton , kernel list , sfr@canb.auug.org.au Subject: Re: next-20190708: kernel BUG at lib/lockref.c:189, softlockups in shrink_dcache...? Message-ID: <20190711072423.GA4219@amd> References: <20190710201311.GA8519@amd> <20190710170912.dd53d6539127bb5b7536788d@linux-foundation.org> <20190711002527.GD17978@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="lrZ03NoBR/3+SXJZ" Content-Disposition: inline In-Reply-To: <20190711002527.GD17978@ZenIV.linux.org.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --lrZ03NoBR/3+SXJZ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu 2019-07-11 01:25:27, Al Viro wrote: > On Wed, Jul 10, 2019 at 05:09:12PM -0700, Andrew Morton wrote: > > On Wed, 10 Jul 2019 22:13:11 +0200 Pavel Machek wrote: > >=20 > > > Hi! > > >=20 > > > I'm getting some nastyness from lockref / memory management. > > >=20 > > > Any ideas? Any ideas who to talk to? > > >=20 > >=20 > > I'd be suspecting Al's a99d7580f66e737 ("Teach shrink_dcache_parent() > > to cope with mixed-filesystem shrink lists"). >=20 > It is, and it's already fixed. See 9bdebc2bd1c4 with fixes folded in; > the incremental is >=20 > diff --git a/fs/dcache.c b/fs/dcache.c > index d8732cf2e302..01b8cae41a71 100644 > --- a/fs/dcache.c > +++ b/fs/dcache.c > @@ -1555,7 +1555,9 @@ void shrink_dcache_parent(struct dentry *parent) > d_walk(parent, &data, select_collect2); > if (data.victim) { > struct dentry *parent; > + spin_lock(&data.victim->d_lock); > if (!shrink_lock_dentry(data.victim)) { > + spin_unlock(&data.victim->d_lock); > rcu_read_unlock(); > } else { > rcu_read_unlock(); Thanks! It only happened once under high load, so it seems it will not be coming back. Pavel =09 --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --lrZ03NoBR/3+SXJZ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAl0m5CcACgkQMOfwapXb+vJQvwCdHiNqf81kN0h6xHfjqhT3+s7P 7gwAnAxjVW+ePAtfguOzBd0DyRDTZl2S =B9pD -----END PGP SIGNATURE----- --lrZ03NoBR/3+SXJZ--