Messages in this thread | | | Date | Fri, 12 Jun 2015 09:23:02 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 07/12] x86/virt/guest/xen: Remove use of pgd_list from the Xen guest code |
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:
> On Thu, Jun 11, 2015 at 1:37 PM, Linus Torvalds > <torvalds@linux-foundation.org> wrote: > > > > Don't use "for_each_process_thread(g, p)". You only care about each mm, and > > threads all share the same mm, so just do > > > > for_each_process(p) > > > > instead of iterating over all threads too. > > Hmm. I may be wrong. It strikes me that one of the group leaders might have > exited but the subthreads live on. We'd see p->mm being NULL, even though the mm > was originally in use. > > Ugh. So maybe the code really does need to iterate over all threads.
Yeah, for_each_process() is indeed no guarantee that we iterate over all mm's.
We might make it so: but that would mean restricting certain clone_flags variants - not sure that's possible with our current ABI usage?
Thanks,
Ingo
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