* 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 -- 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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