David P. Reed wrote: > Replace use of outb to "unused" diagnostic port 0x80 for time delay > with udelay based time delay on x86_64 architecture machines. Fix for > bugs 9511 and 6307 in bugzilla, plus bugs reported in > bugzilla.redhat.com. > > Derived from suggestion (that didn't compile) by Pavel Machek, and > tested, also based on measurements of typical timings of out's > collated by Rene Herman from many in the community. > > This patch fixes a number of bugs known to cause problems on HP > Pavilion dv9000z and dv6000z laptops - in the form of solid freezes > when hwclock is used to show or set the time. Also, it potentially > improves bus utilization on SMP machines, by using a waiting process > that doesn't tie up the ISA/LPC bus for 1 or 2 microseconds. >
kvm will forward a virtual machine's writes to port 0x80 to the real port. The reason is that the write is much faster than exiting and emulating it; the difference is measurable when compiling kernels. Now if the cause is simply writing to port 0x80, then we must stop doing that. But if the reason is the back-to-back writes, when we can keep it, since the other writes will be trapped by kvm and emulated. Do you which is the case? -- Any sufficiently difficult bug is indistinguishable from a feature. ------------------------------------------------------------------------- SF.Net email is sponsored by: Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
