On Mon, 31 Mar 2014 18:32:40 +0200 (CEST) Thomas Gleixner <[email protected]> wrote:
> On Mon, 31 Mar 2014, Vince Weaver wrote: > > > > This turned up with the perf_fuzzer, haswell, 3.14. > > > > I'm not sure if this is related to the other object corruption bug I am > > seeing. The sympstoms are similar (BUG when dereferencing low invalid > > kernel address) but this time the hrtimer code is not involved at all. > > > > This isn't reproducible, that is if I re-run the fuzzer with the same > > random seed after reboot the bug doesn't trigger. > > > > > > [ 5498.573458] BUG: unable to handle kernel NULL pointer dereference at > > 000000000000006c > > [ 5498.585181] IP: [<ffffffff81189111>] kfree+0x91/0x220 > > [ 5498.593887] PGD 0 > > [ 5498.599365] Oops: 0000 [#1] SMP > > [ 5498.606127] Dumping ftrace buffer: > > [ 5498.612973] (ftrace buffer empty) > > [ 5498.619868] Modules linked in: nfsd auth_rpcgss ..... > > [ 5498.720303] CPU: 1 PID: 13 Comm: ksoftirqd/1 Tainted: G W > > 3.14.0+ #14 > > It's already tainted with W, so there was a warning before that > crash. It would be interesting to see that as well. > Agreed, as the crash points to some pretty straight forward code. If something happened to a task, it can corrupt the task ret_stack pointer which would cause ftrace_graph_exit_task() to crash too. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
