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charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: joey.gouly@arm.com, linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, broonie@kernel.org, catalin.marinas@arm.com, dave.hansen@linux.intel.com, oliver.upton@linux.dev, shuah@kernel.org, will@kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-Stat-Signature: kjks5y5xzi3538e8ujitd6eiq8pytkx3 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: D8CBC140004 X-Rspam-User: X-HE-Tag: 1701359508-457564 X-HE-Meta: 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 V6SFF1qd zzKlVXQzpRQDvOZ2bmVurDiqBT0ccbADfAkleEFOjUfYtwTq7mJ5H0bx+hfJf3a+UfI1wxi4Ysvic2u9J9eEHDtFgu8Ryhb0qvdrz0Z23ka60xrP43bBnf1/YFFl7u67XqY8ncStynDgwGWtchh0BIowl+Sl8e4nSYKq3YssKOJ0mXUttkQ6mvk3DY5+pb6aCIlfYXyXy6rjMc3YEcCCG9VrPNK6m+YtoGVqsoeMxBd3wM61MFI7j/CXF8w== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 24 Nov 2023 16:34:51 +0000, Joey Gouly wrote: > > Define the new system registers that POE introduces and context switch them. Thinking about it some more, I don't think this is enough. One fundamental thing that POE changes is that read permissions can now be removed from S1 by the guest. Which means that if we take a (for example) a permission fault at S2 and perform (as we do today) a "AT S1E1R" to obtain the faulting IPA, we can end-up with a failing translation because POE, under control of the guest, has removed the read permission. Which is why FEAT_ATS1A exists, and ignores permission overlays so that we can get to the IPA. I think this means we need to teach __translate_far_to_hpfar() about AT S1E1A Thanks, M. -- Without deviation from the norm, progress is not possible.