On Wed, May 11, 2016 at 06:17:51PM +0000, Abhishek Kulkarni wrote: > Thanks very much Mark. Should I raise a bug about this on freebsd.org?
That would be helpful, thanks. > > Regards > Abhishek Kulkarni > > > > > On 5/11/16, 9:49 AM, "Mark Johnston" <[email protected] on behalf of > [email protected]> wrote: > > >On Sat, May 07, 2016 at 08:55:56PM +0000, Abhishek Kulkarni wrote: > >> Hello All, > >> > >> I was using Dtrace using the FBT provider on an arm platform with witness > >> enabled. When FBT is used with the kernel module, it generates a kernel > >> panic or the system becomes unresponsive. Is this problem know or seen > >> before. I am copying the kernel backtrace below for reference. The issue > >> seems to be with a blockable sleep lock(kld_sx) acquired which is > >> conflicting with the td->td_critnest positive value. > > > >Unfortunately, I think this is expected. The ARM port of DTrace will > >call into the kernel linker from probe context to perform stack > >unwinding. This is a bug since the kernel linker cannot be entered in > >arbitrary contexts - the thread might already hold the linker lock, or > >might hold a critical section as in your example. > > > >This is a known issue, but I'm not sure if anyone is working on fixing > >it. > > > >-Mark _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-dtrace To unsubscribe, send any mail to "[email protected]"
