On Tue, Aug 21, 2012 at 03:09:30PM +0200, Oleg Nesterov wrote: ...
> > This is true for Intel like architectures that have *one* swbp > > instruction. On Powerpc, gdb for instance, can insert a trap variant at > > the address. Therefore, is_swbp_insn() by definition should return true > > for all trap variants. > > Not in this case, I think. > > OK, I was going to do this later, but this discussion makes me think > I should try to send the patch sooner. > > set_swbp()->is_swbp_at_addr() is simply unneeded and in fact should > be considered as unnecessary pessimization. > > set_orig_insn()->is_swbp_at_addr() makes more sense, but it can't fix > all races with userpace. Still it should die. > > > OK. I will separate out the is_swbp_insn() change into a separate patch. > > Great thanks. And if we remove is_swbp_insn() from set_swbp() and > set_orig_insn() then the semantics of is_swbp_insn() will much more > clear, and in this case I powerpc probably really needs to change it. Oleg, I have posted a new version for review [1] without the is_swbp_insn() change. I will await your changes around is_swbp_at_addr() and make changes to the powerpc code if necessary. Regards, Ananth [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-August/100524.html _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
