On Thu, Dec 01, 2011 at 09:44:37AM +0100, Markus Trippelsdorf wrote: > On 2011.11.24 at 09:50 +0100, Markus Trippelsdorf wrote: > > On 2011.11.23 at 10:06 -0600, Christoph Lameter wrote: > > > On Wed, 23 Nov 2011, Markus Trippelsdorf wrote: > > > > > > > > FIX idr_layer_cache: Marking all objects used > > > > > > > > Yesterday I couldn't reproduce the issue at all. But today I've hit > > > > exactly the same spot again. (CCing the drm list) > > > > > > Well this is looks like write after free. > > > > > > > ============================================================================= > > > > BUG idr_layer_cache: Poison overwritten > > > > ----------------------------------------------------------------------------- > > > > Object ffff8802156487c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > > > Object ffff8802156487d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > > > Object ffff8802156487e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > > > Object ffff8802156487f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > > > Object ffff880215648800: 00 00 00 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b ....kkkkkkkkkkkk > > > > Object ffff880215648810: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > > > > > And its an integer sized write of 0. If you look at the struct definition > > > and lookup the offset you should be able to locate the field that > > > was modified. > > It also happens with CONFIG_SLAB. > (If someone wants to reproduce the issue, just run a kexec boot loop and > the bug will occur after a few (~10) iterations.) > Can you provide the kexec command line you are using and full kernel log (mostly interested in kernel option). Cheers, Jerome -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>