NVIDIA: SAUCE: target/arm: Add sysfs detection for KVM CCA capability#12
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ianm-nv wants to merge 1 commit intoNVIDIA:nvidia_unstable-10.1from
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NVIDIA: SAUCE: target/arm: Add sysfs detection for KVM CCA capability#12ianm-nv wants to merge 1 commit intoNVIDIA:nvidia_unstable-10.1from
ianm-nv wants to merge 1 commit intoNVIDIA:nvidia_unstable-10.1from
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Add runtime detection of the KVM CCA capability number by reading from the kernel's sysfs module parameter. This allows QEMU to automatically discover the correct capability number without needing version-specific hardcoded values that may become stale. The ARM CCA host patches underwent a naming change from RME to RMI in v11: - v10 (Linux 6.17): KVM_CAP_ARM_RME, sysfs param kvm_cap_arm_rme - v11 (Linux 6.18+): KVM_CAP_ARM_RMI, sysfs param kvm_cap_arm_rmi Detection order: 1. Try v11 sysfs path (/sys/module/kvm/parameters/kvm_cap_arm_rmi) 2. Try v10 sysfs path (/sys/module/kvm/parameters/kvm_cap_arm_rme) 3. Fall back to uname detection for 6.16 dev kernel (capability == 243) 4. Use compile-time KVM_CAP_ARM_RME as last resort This allows the same QEMU binary to work with linux-nvidia-6.16 (dev), linux-nvidia-6.17 (v10 host patches), and linux-nvidia-6.18+ (v11 host patches). Signed-off-by: Ian May <ianm@nvidia.com>
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LGTM!
Acked-by: Matthew R. Ochs <mochs@nvidia.com>
NathanChenNVIDIA
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LGTM
Acked-by: Nathan Chen nathanc@nvidia.com
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Merged, closing PR. |
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Add runtime detection of the KVM CCA capability number by reading from the kernel's sysfs module parameter. This allows QEMU to automatically discover the correct capability number without needing version-specific hardcoded values that may become stale.
The ARM CCA host patches underwent a naming change from RME to RMI in v11:
Detection order:
This allows the same QEMU binary to work with linux-nvidia-6.16 (dev), linux-nvidia-6.17 (v10 host patches), and linux-nvidia-6.18+ (v11 host patches).
Here is a ref to the kernel patch that enables the sysfs capability.
I've tested this with the following kernels:
6.16-pset
6.17-nvidia-devel
6.17-nvidia
6.18-nvidia