[PATCH kernel v2 4/4] powerpc/pseries/svm: Allow IOMMU to work in SVM

[Thiago Jung Bauermann]

Alexey Kardashevskiy <aik at ozlabs.ru> writes:

> H_PUT_TCE_INDIRECT uses a shared page to send up to 512 TCE to
> a hypervisor in a single hypercall. This does not work for secure VMs
> as the page needs to be shared or the VM should use H_PUT_TCE instead.
>
> This disables H_PUT_TCE_INDIRECT by clearing the FW_FEATURE_PUT_TCE_IND
> feature bit so SVMs will map TCEs using H_PUT_TCE.
>
> This is not a part of init_svm() as it is called too late after FW
> patching is done and may result in a warning like this:
>
> [    3.727716] Firmware features changed after feature patching!
> [    3.727965] WARNING: CPU: 0 PID: 1 at (...)arch/powerpc/lib/feature-fixups.c:466 check_features+0xa4/0xc0
>
> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>

Reviewed-by: Thiago Jung Bauermann <bauerman at linux.ibm.com>
Tested-by: Thiago Jung Bauermann <bauerman at linux.ibm.com>

-- 
Thiago Jung Bauermann
IBM Linux Technology Center