RFR(m): 8074552: SafeFetch32 and SafeFetchN do not work in error handling

[Andrew Dinn]

On 19/03/15 09:35, Thomas Stüfe wrote:
> this may be the case. I do not know the zero port very good.
> 
> SefeFetch handling needs support from both signal handler and access
> routines to ucontext_t (ucontext_set_pc(), ucontext_get_pc()). Both is
> missing.
> 
> In theory it could be added, because doing so requires no assembly of any
> sorts. But it looks like the zero port avoids any technique which requires
> fiddling around with the ucontext_t in the signal handler to jump to a
> continuation point. This looks intentional and I do not want to introduce
> any code which breaks the intention of zero port.
> 
> Of course, the other way would be just to disable the test for zero.
> 
> What would be the right way?

Coleen, thanks very much for checking to see if this fix causes an issue
for zero.

Thomas, I have pointed the relevant Red Hat developers at this thread.
One of them should respond soon.

regards,


Andrew Dinn
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