On 2021-03-25 09:14, Shameer Kolothum wrote:
From: Marc Zyngier maz@kernel.org
commit 9739f6ef053f104a997165701c6e15582c4307ee upstream.
It looks like we have broken firmware out there that wrongly advertises a GICv2 compatibility interface, despite the CPUs not being able to deal with it.
To work around this, check that the CPU initialising KVM is actually able to switch to MMIO instead of system registers, and use that as a precondition to enable GICv2 compatibility in KVM.
Note that the detection happens on a single CPU. If the firmware is lying *and* that the CPUs are asymetric, all hope is lost anyway.
Cc: stable@vger.kernel.org #5.10 Reported-by: Shameerali Kolothum Thodi shameerali.kolothum.thodi@huawei.com Tested-by: Shameer Kolothum shameerali.kolothum.thodi@huawei.com Signed-off-by: Marc Zyngier maz@kernel.org Message-Id: 20210305185254.3730990-8-maz@kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Shameer Kolothum shameerali.kolothum.thodi@huawei.com
Please hold on on that.
This patch causes a regression, and needs a fix that is currently queued for 5.12 [1]. Once this hits upstream, please add the fix to the series and post it as a whole.
Thanks,
M.
[1] https://lore.kernel.org/r/20210323162301.2049595-1-maz@kernel.org