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 00:57:01 +0300 Message-ID: <20150228215701.GA1732@nest> References: <20150203191507.GA2374@crion86> <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> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0883492824==" Return-path: In-Reply-To: <20150228211013.GB13459@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 --===============0883492824== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="CE+1k2dSO48ffgeK" Content-Disposition: inline --CE+1k2dSO48ffgeK Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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 warnings = mentioned in > > previous mail: > >=20 > > [ 26.922953] WARNING: CPU: 1 PID: 767 at drivers/gpu/drm/i915/i915_ge= m.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. (Che= ck > /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_detect > changes that is at the heart of the issue here. (Admittedly he did say > it was worthy of a drink or two.) > -Chris 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 Best regards, Andrey Skvortsov --CE+1k2dSO48ffgeK Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJU8jmtAAoJEAF8y6L1SLCtvXIQAMyHy8pDFAUxIfh1QWROdmBG iI3koyi4wnggPF3BgA+EhT/okbUXWSMQ8qcqUH7FeExfXbk4B41MuqH4dJs9iwwK pBxk4AMP3g0XSO5cltv4Wlnn3lxSOBhauHzNgiUChzeH6V+7IndrNkL+gL0fUjVh V9rJFUW477syzdFL39v1sLdUWBzzHQttxmzNpt4di045l3/AXv0JMXUDEeMspYtv ig3i5/qtI2/SD7u/j4MFZ/LN90fwaFu5R2I4Ud6lBvnmbZ9IkgQYzCna/vnP6ztb q9EU74fOLHH4L3qWGXQ+U3MkG3S/GOGBZN+XSFZ0nWvuFHqmk1IafeSOFDuo9pHZ lzPwRdTyymZ/Eq0a7c7zy8CapjhNYtcxCvBfym/x2hJ6aDkk4+s+Cgio3Xs7y+P6 lITimzAsXp21QS7TIf9CxRgawdyu61jnI+1FrDvsjwwXOZts6HBqeip0Oz939FSC hkP0fDQ/HDBT77g0vOXfSqKysIm2GIXA9GXIEYhR3fhklWYtMe+yd3XUtTbcSIwC cjryr5F4riHTJSBo8pkYl7yjHzLgU/btQbZQkMlafPWPNmcFLVQ78T0x+wOprMYZ zw2of0sDJevh3Ehcwe0NvCgzvzaYa4rpESLth+b/ZIWvhpw8gkA7V59FXi10ihT/ fSvYzpHXCjEFFL/Re/hO =gBCG -----END PGP SIGNATURE----- --CE+1k2dSO48ffgeK-- --===============0883492824== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4 IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9saXN0 cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK --===============0883492824==--