Date: Sun, 21 Jul 2013 10:11:24 +0300 From: Konstantin Belousov <kostikbel@gmail.com> To: Andriy Gapon <avg@FreeBSD.org> Cc: freebsd-fs@FreeBSD.org Subject: Re: Deadlock in nullfs/zfs somewhere Message-ID: <20130721071124.GY5991@kib.kiev.ua> In-Reply-To: <51E99477.1030308@FreeBSD.org> References: <CAJ-Vmonk2HAzX38-mbL8hwxiUfL6JyJrMTq0dTBctW=P4dfyEQ@mail.gmail.com> <51E7B686.4090509@FreeBSD.org> <20130718112814.GA5991@kib.kiev.ua> <51E7F05A.5020609@FreeBSD.org> <20130718185215.GE5991@kib.kiev.ua> <51E91277.3070309@FreeBSD.org> <20130719103025.GJ5991@kib.kiev.ua> <51E95CDD.7030702@FreeBSD.org> <20130719184243.GM5991@kib.kiev.ua> <51E99477.1030308@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
--YDTWxoC2E3hrC6hC Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jul 19, 2013 at 10:33:11PM +0300, Andriy Gapon wrote: > on 19/07/2013 21:42 Konstantin Belousov said the following: > > Then, you cannot use VFS suspension. Or, in other words, you are direc= ted > > to abuse the VFS interface. I assure you that any changes to the inter= face > > would not take into account such abuse and probably break your hack. >=20 > So what would be your recommendation about this problem? > Should we add another flavor of VFS suspension? > The one that would mean "all external accesses to this fs must be put on = hold", > but would not imply "this fs is frozen". Suspension is very complicated as it is. Adding another flavour would multiply the current mess^H^H^H^H collection of subtleties. IMO, the best route is to use the KPI properly, i.e. adding the vn_start_write() braces around the top-level entries in the mutating code paths. --YDTWxoC2E3hrC6hC Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (FreeBSD) iQIcBAEBAgAGBQJR64mcAAoJEJDCuSvBvK1BPpgP/05QbPS6lUQ+FEpuwUx7WyBl ZpnCHn2NmkncxS0CslgHxK2BvdsG11pRByk2Q9pw1BcqIarudf0K9emnNNC5erZs jdkYJIJgXHFwfrJsPP+TZbt6NPoPy27qsRtO1SQ+dvYF29ia+K5GZEB17ABrU3wZ TZkJZBH5fF96TFgb/epGD32V5a+s9cVahBrTHvbldFR1fLCMopXFk/SchuHkOsa+ R8Nr7Vg9zxfHKx91a/QUDJkbK7W+dpYphBaXT/wNQ5D8XISPBzKA115wsoJbXjMx ytPsHAugd9w2+tUJNTIHzJ9LGAPNdXdAzxESncERytDbccNm3s/tdjPlH1aCgjVt OrVAJY0p+XkPcAGpANiGpHGKUHsy3M7H4TDbCu+bV1Jnb25dpAf0GTuCoSiELaKr teMPld/vi4qqNUE77yvS20xbybCiCHH3Wwz/J3dGopjkycxdq6wCK+1Zv7N1uv1c 5rNGvezXQv6kL7fD/hTLS5EvvAsFsRsb1ZABeJfU9H1qOur66/A1J4gJs9y969I8 RE8Te2aKP7ETHMUsL70RZPaSywqjZNMt1BcJWFOJNkeui/so55W1+2k4t3AfDoSs jbZcibwKAE6OGb46w+PFLNPKWFfNWk7cU8MWSYwane9YuMdzQakTG+5YBP/8O6KY a12tyQ+ZH88pJFF6CZ/z =Y0Y6 -----END PGP SIGNATURE----- --YDTWxoC2E3hrC6hC--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20130721071124.GY5991>