On 16.10.2015 17:08, Sergey Fedorov wrote: > On 16.10.2015 04:14, Richard Henderson wrote: >> On 10/16/2015 03:36 AM, Peter Maydell wrote: >>> On 14 October 2015 at 22:02, Richard Henderson <r...@twiddle.net> wrote: >>>> On 10/15/2015 06:34 AM, Peter Maydell wrote: >>>>> This is still the same cryptic comment we have in the >>>>> targets which do do this. Can we have something >>>>> that is a bit more explanatory about what is going on and >>>>> why we need to do this, please? >>>> >>>> Suggestions? >>> ...well, I don't entirely understand the problem it's >>> fixing, which is why I'm asking for a better comment :-) >> Heh. Fair enough. How about >> >> /* The address covered by the breakpoint must be included in >> [tb->pc, tb->pc + tb->size) in order to for it to be >> properly cleared -- thus we increment the PC here so that >> the logic setting tb->size below does the right thing. */ >> >> There are two edge cases that cause the problem with clearing that >> could be described, but I think that the comment becomes too bulky, as >> well as confuses the situation for someone cutting-and-pasting the >> logic to a new port. > Maybe we could rather fix that condition in > tb_invalidate_phys_page_range()? It seems weird that it can't handle a > zero-sized TB.
I think extending "!(tb_end <= start || tb_start >= end)" condition to "!(tb_end <= start || tb_start >= end) || tb_start == start" would work fine. Thoughts? I could prepare a patch for that. Best regards, Sergey
