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Adding check to forward only if the hvc is trapped >>>> from the nested VM. >>> >>> I disagree. HVC from EL2 must be routed to the same EL2. HVC from EL1 >>> must be routed to the EL2 controlling EL1. >> >> Thanks, Understood, In NV case, hvc has to be forwarded to L1 >> irrespective of it origin (L1 or L2). Need to add hvc handler in the >> smccc_filter.c for the vm (when run as L1), so that it is handled and >> returns with required args set. > > Why? This test checks under which conditions an HVC/SMC gets routed to > userspace. What does it even mean to test HVC if it doesn't make it > outside of the guest itself? smccc_filter.c has 2 tests (test_filter_denied and test_filter_fwd_to_user), which runs the vm(guest_code). I was trying to modify test_filter_denied to run in vEL2, which led to this patch/discussion. I agree, it does not makes sense to run this test for vEL2. test_filter_fwd_to_user is not feasible to run in vEL2. Thanks for the feedback. BTW, I could add hvc handler and run test_filter_denied in vEL2. -- Thanks, Ganapat/GK