On 09/03/2009 02:18 PM, Ingo Molnar wrote: > > * H. Peter Anvin <hpa@xxxxxxxxx> wrote: > >> On 09/03/2009 01:45 PM, Jeremy Fitzhardinge wrote: >>> >>> Two problems: >>> >>> * gcc generates %gs: references for stack-protector, but we use %fs >>> for percpu data (because restoring %fs is faster if it's a null >>> selector; TLS uses %gs). I guess we could use %fs if >>> !CONFIG_CC_STACKPROTECTOR, or %gs if we are using it (though that >>> has some fiddly ramifications for things like ptrace). >> >> Well, by touching two segments we're getting the worst of both >> worlds, so at least assuming some significant number of real-world >> deployments use CC_STACKPROTECTOR, we really don't want to >> pessimize that case too much. > > Fedora has stackprotector enabled so it's used in a widespread way. > > Ingo I'm guessing most distros do, except perhaps embedded ones. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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