Thanks Ray.
>
> 1. It's not "LockedCpuCount". It's "ArrivedCpuCountUponLock".
> Comments can be:
> Before the door is locked, CpuCount stores the arrived CPU count.
> After the door is locked, CpuCount is set to -1 indicating the door is
> locked.
> ArrivedCpuCpuntUponLock stores the arrived CPU count then.
>
>
Ok, I will update.
> > +/**
> > + Performs an atomic compare exchange operation to get semaphore.
> > + The compare exchange operation must be performed using MP safe
> > + mechanisms.
> > +
> > + @param[in,out] Sem IN: 32-bit unsigned integer
> > + OUT: original integer - 1 if Sem is not locked.
> > + OUT: original integer if Sem is locked
> > (MAX_UINT32).
> > +
> > + @retval Original integer - 1 if Sem is not locked.
> > + Original integer if Sem is locked (MAX_UINT32).
>
> 2. Can just say "MAX_UINT32 if Sem is locked".
>
>
Agree.
> > +
> > + //
> > + // Assign CPU Semaphore pointer
> > + //
> > + CpuSem = (*Context)->CpuSem;
> > + for (CpuIndex = 0; CpuIndex < NumberOfCpus; CpuIndex++) {
> > + CpuSem->Run = (SMM_CPU_SYNC_SEMAPHORE *)SemAddr;
> > + *CpuSem->Run = 0;
> > +
> > + CpuSem++;
> > + SemAddr += OneSemSize;
>
> 5. SafeIntLib was used earlier to make sure no integer overflow.
> But "SemAddr += OneSemSize" is simply ignoring the danger of integer
> overflow.
> I agree (NumberOfCpus + 1) * OneSemSize shouldn't cause integer overflow
> when code runs to here.
> But initial value of SemAddr is not zero. It's still possible the SemAddr +
> (NumberOfCpus+1)*OneSemSize causes integer overflow.
> I am ok if you don't fix it as I don't believe the integer overflow could
> happen
> in 5 years.
SemAddr is the address of allocated buffer (SemBuffer), "SemAddr +=
OneSemSize" will make SemAddr point to the part of allocated buffer. is it
possible integer overflow? If so, the allocatepage should fail?
Thanks,
Jiaxin
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