From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Skvortsov Subject: Re: [Regression] BUG: unable to handle kernel NULL pointer dereference Date: Sun, 1 Mar 2015 12:30:01 +0300 Message-ID: <20150301093001.GA1696@nest> References: <20150203202152.GD5784@nuc-i3427.alporthouse.com> <20150204182627.GA2272@crion86> <20150204184217.GG10991@nuc-i3427.alporthouse.com> <20150223201239.GC3871@crion86> <20150223212031.GI15204@nuc-i3427.alporthouse.com> <20150223234245.GA24485@phenom.ffwll.local> <20150228122037.GA12590@nest> <20150228211013.GB13459@nuc-i3427.alporthouse.com> <20150228215701.GA1732@nest> <20150301082920.GC13459@nuc-i3427.alporthouse.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0095322673==" Return-path: In-Reply-To: <20150301082920.GC13459@nuc-i3427.alporthouse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Chris Wilson , Daniel Vetter , Jani Nikula , David Airlie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Sitsofe Wheeler List-Id: dri-devel@lists.freedesktop.org --===============0095322673== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="3V7upXqbjpZ4EhLz" Content-Disposition: inline --3V7upXqbjpZ4EhLz Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 01 Mar, Chris Wilson wrote: > On Sun, Mar 01, 2015 at 12:57:01AM +0300, Andrey Skvortsov wrote: > > On 28 Feb, Chris Wilson wrote: > > > On Sat, Feb 28, 2015 at 03:20:37PM +0300, Andrey Skvortsov wrote: > > > > Unfortunately this is not the last bug, that breaks i915/drm working > > > > on my laptop. Sometimes system successfully loads with couple warni= ngs mentioned in > > > > previous mail: > > > >=20 > > > > [ 26.922953] WARNING: CPU: 1 PID: 767 at drivers/gpu/drm/i915/i91= 5_gem.c:4525 i915_gem_free_object+0x13f/0x288 [i915]() > > > > [ 26.922954] WARN_ON(obj->frontbuffer_bits) > > >=20 > > > That's inocuous, but for the serious hang, you may want to try > > > video=3DSVIDEO-1:d on the kernel commandline to workaround the hang. = (Check > > > /sys/class/drm/card/ for the actual name of the connector for TV). I > > > think Ville mentioned he was looking/looked at the atomic-vs-load_det= ect > > > changes that is at the heart of the issue here. (Admittedly he did say > > > it was worthy of a drink or two.) > > > -Chris > >=20 > > Thank you for the help. I've tried to add to the kernel command line > > 'video=3Dcard0-SVIDEO-1:d video=3Dcard0-VGA-1:d'. But despite of that > > kernel crashes with 'BUG: unable to handle kernel NULL pointer > > dereference at' occasionally. >=20 > Remove the card0- and combine both into a single video=3D stanza: > video=3DSVIDEO-1:d,VGA-1:d I've just tried that, but the crash with NULL pointer dereference still hap= pens. --=20 Best regards, Andrey Skvortsov Secure e-mail with gnupg: See http://www.gnupg.org/ PGP Key ID: 0x57A3AEAD --3V7upXqbjpZ4EhLz Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJU8twZAAoJEAF8y6L1SLCthNgP/1d5iHvy1OfLvlCjQwrqb9o2 eEVMzi+mU+pmiyk15W/61TYzfI1l0eisG0f4z+YWFWqeyostjYZ/v2hHxdZE/klZ OXDqSKyMTEgImKZMpU4zoOPd9OOQ38QMx6l69JXAW2bS5iEaR/m5ovK31VsZuRzj ZRt6eO3znhdW1i+fVejnAdec/xMiUEI20vybZ91ZPraGIgkMWh2WI7FeKVVQGLMj KZPOPjHU0kIIFio6/urA5Wk+E+A17AqCs4x0kYX2KuqjI1x9gQ+7fHmpyhqCYXkv xEqHKcQvFw7RTut8sNw9YKbj5k5OCvO2Q88Sm+w8cRgc/M8F7uFmJ/PRix8AGh4I f5aPJNPZYEU+vu6Sj0kG3+tAvfcO8wzbztI8fwazbq1A1wX23r2PMeyyP/dnomdg bI/gdy+P3ZHuPjoGc1EUV6XyyHufKaYLrdIfc4A+ZVn/8GOQVHQIf1KyORLpWKJ6 HmY+1FlKpF3QMcjpqSR+j7CAWdgJsmIUL2eFXhAyTVQPGiLMfZ0Yj2F5hHHOs0H2 PFNLz46k8TFL19wJbOS2AKZLhi7JRvFLPxi5OUPuWn/4PYAVua4WEwGlkIzS5yEA KxiF8Ao4EEotBTqqPtYSycLN9g3KBH1WrLrBIsAdMWrUdOoQBxdQvAfpHgFbYHBa uovALhK6zXXItwiKZfE0 =pypy -----END PGP SIGNATURE----- --3V7upXqbjpZ4EhLz-- --===============0095322673== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4 IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9saXN0 cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK --===============0095322673==--