Messages in this thread | | | Date | Wed, 17 Feb 2010 17:03:50 +0100 | From | Frederic Weisbecker <> | Subject | Re: Regression in ptrace (Wine) starting with 2.6.33-rc1 |
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On Mon, Feb 15, 2010 at 11:47:24AM -0800, Roland McGrath wrote: > > - The other one with 'locally'/'globally' enabled breakpoints. > > There is no "local/global" enablement. That distinction is meaningless > given the way the kernel uses the hardware. Which of those bits you set > has no material effect on the watchpoint/trap behavior.
Yeah.
> The only regression is in the observed bit pattern read back from dr7. > To be 100% compatible, the hw_breakpoint ptrace-compatibility front-end > should record the state of the useless bits to report back, so the only > differences from the bit pattern written are whatever ones the real > hardware would have shown from writing dr7 and reading it back.
Agreed. We have to match the previous ABI, it's a regression.
We have the NULL breakpoint address thing fixed (will push it to Ingo). We now need to fix the local/global flag storage.
The fastest way to do so is to keep a per thread dr7 variable. I'm looking at it and will send a fix soon.
We can think about something proper later.
Thanks.
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