>[mailto:xen-devel-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Keir Fraser
>Sent: Wednesday, August 10, 2005 9:12 PM
>On 10 Aug 2005, at 14:01, Gerd Knorr wrote:
>>> Sure? The patch below fixes it for me.
>> Uhm, well, it doesn't really fix it.
>>> The tlbflush stuff is red herring btw, the real difference is
>>> optimization. Build with "optimize=n" boot fine, others don't.
>> While looking into this I've noticed the bug comes and goes away
>> with the optimization level. Building with -O1 works fine,
>> building with -O2 breaks (both with the patch mailed applied).
>> There might be something wrong with the inline assembler ...
>See the fix I just this minute checked in :-)
>Hopefully it should fix all these weirdnesses....
> -- Keir
Is similar fix also required by __put_user_64?
#define __put_user_u64(x, addr, retval, errret) \
: "=r"(retval) \
: "A" (x), "r" (addr), "i"(errret), "0"(retval))
I'm not sure exact rules for compiler to choose registers. But once
compiler optimizes retval or addr to reuse eax/edx under some condition,
user will also see either incorrect return value, or incorrect content
written to incorrect address. Can we assume such optimization never
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