>>> On 23.01.18 at 10:58, <jgr...@suse.com> wrote: > On 23/01/18 10:26, Jan Beulich wrote: >>>>> On 22.01.18 at 13:32, <jgr...@suse.com> wrote: >>> show_guest_stack() and compat_show_guest_stack() stop dumping the >>> stack of the guest whenever its virtual address reaches the same >>> alignment which is used for the hypervisor stacks. >>> >>> Remove this arbitrary limit and try to dump a fixed number of lines >>> instead. >> >> Hmm, I can see your point, but before looking at the change in detail >> I think we need to agree on what behavior we want. Dumping >> arbitrary data as if it was a part of the stack isn't very helpful, limiting >> the risk of which is, I think, the reason for the way things currently >> work (assuming that guest kernels won't have stacks larger than Xen >> itself, and that they too would align them). What would perhaps be >> better is for the guest to supply information about the restrictions it >> enforces on its stacks, which Xen could then use here. In the >> absence of such hints using the values currently being used would >> possibly make sense. > > Currently the stack dump will have the same fixed number of lines as > with my patch. I'm only removing the premature end of dumping whenever > the stack address crosses a 32kB boundary. Linux 64 bit pv guests are > using 16kB stack size. So using this boundary would be more natural.
IOW your change converts a 50:50 chance of dumping non-stack data to 100% (all in case the stack pointer isn't far away from the stack start). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
