On Sat, 2011-07-30 at 14:53 -0600, David Ahern wrote: > A page fault occurred walking the callchain while creating a perf > sample for the context-switch event. To handle the page fault the > mmap_sem is needed, but it is currently held by setup_arg_pages. > (setup_arg_pages calls shift_arg_pages with the mmap_sem held. > shift_arg_pages then calls move_page_tables which has a cond_resched > at the top of its for loop - hitting that cond_resched is what caused > the context switch.) > > This is an extension of Anton's proposed patch: > https://lkml.org/lkml/2011/7/24/151 > adding case for 32-bit ppc. > > Tested on the system that first generated the panic and then again > with latest kernel using a PPC VM. I am not able to test the 64-bit > path - I do not have H/W for it and 64-bit PPC VMs (qemu on Intel) > is horribly slow. > > Signed-off-by: David Ahern <dsah...@gmail.com> > CC: Benjamin Herrenschmidt <b...@kernel.crashing.org> > CC: Anton Blanchard <an...@samba.org>
Hmm, Paul, didn't you fix something like this early on? Anyway, I've no objections since I'm really not familiar enough with the PPC side of things. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
