Hi guys,
> -----Original Message----- > From: James Morse [mailto:james.mo...@arm.com] > Sent: Friday, February 15, 2019 3:23 AM > To: Mark Rutland; Zhang, Lei > Cc: 'Will Deacon'; 'Catalin Marinas'; 'linux-kernel@vger.kernel.org'; > 'linux-arm-ker...@lists.infradead.org' > Subject: Re: [PATCH v4] arm64: Add workaround for Fujitsu A64FX erratum 010001 > I think we should do this: never set NFDx on A64FX. I don't think we can > maintain > the TCR > swivel before any memory access in the KPTI trampoline. (It already uses the > FAR as a > scratch register!) > > The errata means we can't use these bits. Its simpler than trying to work > around > the symptoms. I think you mean it may be a problem to modify the KPTI trampoline because some patches about KPTI will be merged to mainline in the near future. I understood that. I should discuss with my colleagues whether we can set NFDx=0 all of time on A64FX. And thanks for your patch. If we can set NFDx=0 all of time, I will review, test and report the result. Best Regards, Zhang Lei
