Messages in this thread |  | | Date | Mon, 22 Feb 2021 10:35:25 +0100 | From | Jonathan Neuschäfer <> | Subject | Re: [PATCH v7 23/23] [DO NOT MERGE] arm64: Cope with CPUs stuck in VHE mode |
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Hi,
On Mon, Feb 08, 2021 at 09:57:32AM +0000, Marc Zyngier wrote: > It seems that the CPU known as Apple M1 has the terrible habit > of being stuck with HCR_EL2.E2H==1, in violation of the architecture.
Minor nitpick from the sideline: The M1 SoC has two kinds of CPU in it (Icestorm and Firestorm), which makes "CPU known as Apple M1" a bit imprecise.
In practicality it seems unlikely though, that Icestorm and Firestorm act differently with regards to the code in this patch.
Best regards, Jonathan Neuschäfer
> > Try and work around this deplorable state of affairs by detecting > the stuck bit early and short-circuit the nVHE dance. It is still > unknown whether there are many more such nuggets to be found... > > Reported-by: Hector Martin <marcan@marcan.st> > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > arch/arm64/kernel/head.S | 33 ++++++++++++++++++++++++++++++--- > arch/arm64/kernel/hyp-stub.S | 28 ++++++++++++++++++++++++---- > 2 files changed, 54 insertions(+), 7 deletions(-) [...] [unhandled content-type:application/pgp-signature] |  |