[cc list trimmed] Hello Oliver! Fri, Apr 13, 2007 at 04:52:45PM +0200 you wrote: > Using cmpxchg8b with a lock prefix wouldn't be a good idea > anyway. If I remember correctly, the lock cmpxchg8b > combination was the cause of the infamous "F00F" bug of > old Pentium processors. It causes them to freeze. AFAICT the bug only manifested itself when the instruction had an invalid register operand: www.intel.com/support/processors/pentium/ppiie/ : > It is illegal to use a register as the destination. ... If a > register is used as the destination, the processor normally stops > execution of the CMPXCH8B instruction, signals this error > condition and executes an error handler in software. > This erratum occurs if the CMPXCHG8B instruction is also locked ... > and an invalid register destination is used. So normal instructions should be OK. The fix was there to protect the system from malicious code which could hang it. -- DoubleF No virus detected in this message. Ehrm, wait a minute... /kernel: pid 56921 (antivirus), uid 32000: exited on signal 9 Oh yes, no virus:)
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