idr_remove called for id=4096 which is not allocated

[Tommi Rantala]

Hello,

Saw this WARNING a few times while fuzzing the kernel with Trinity in
a qemu virtual machine:

[   22.883257] idr_remove called for id=4096 which is not allocated.
[   22.884487] Pid: 2303, comm: trinity-child1 Not tainted 3.8.0+ #87
[   22.885601] Call Trace:
[   22.886080]  [<ffffffff8134b111>] idr_remove+0x131/0x1f0
[   22.887107]  [<ffffffff8143c678>] drm_ctxbitmap_free+0x38/0x50
[   22.888158]  [<ffffffff8143cbd3>] drm_rmctx+0x63/0x100
[   22.889091]  [<ffffffff8143d710>] drm_ioctl+0x3d0/0x4d0
[   22.890034]  [<ffffffff8143cb70>] ? drm_newctx+0xb0/0xb0
[   22.890970]  [<ffffffff812fb640>] ? avc_has_perm_flags+0x1d0/0x2a0
[   22.892127]  [<ffffffff812fb498>] ? avc_has_perm_flags+0x28/0x2a0
[   22.893218]  [<ffffffff810f5b18>] ? trace_hardirqs_off_caller+0x28/0xd0
[   22.894401]  [<ffffffff810f5bcd>] ? trace_hardirqs_off+0xd/0x10
[   22.895461]  [<ffffffff811b5ff2>] do_vfs_ioctl+0x532/0x580
[   22.896447]  [<ffffffff812fc7d3>] ? file_has_perm+0x83/0xa0
[   22.897453]  [<ffffffff811b609d>] sys_ioctl+0x5d/0xa0
[   22.898429]  [<ffffffff813571de>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[   22.899629]  [<ffffffff81ca07e9>] system_call_fastpath+0x16/0x1b

Tommi