Messages in this thread | | | Subject | Re: [PATCH 3/5] arm64: Detect disabled HVC early | From | Rafał Miłecki <> | Date | Thu, 12 Aug 2021 21:47:18 +0200 |
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On 12.08.2021 21:02, Marc Zyngier wrote: > Having HVC disabled from EL3 while the kernel is entered at EL2 > is a complete nightmare. > > We end-up taking an UNDEF at the worse possible moment (checking > for VHE) and even if we didn't, having KVM enabled would signify > the premature end of the kernel. > > Instead, try and detect this stupid case by issuing a HVC > for HVC_RESET_VECTORS, which does nothing when the stubs > are live. If we get HVC_STUB_ERR back, that's because the > UNDEF handler has kicked in. > > In this situation, close your eyes, block your nose, and gracefully > pretend we have booted at EL1. > > Reported-by: Rafał Miłecki <zajec5@gmail.com> > Signed-off-by: Marc Zyngier <maz@kernel.org>
This does the trick.
Tested-by: Rafał Miłecki <rafal@milecki.pl>
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