forked from Minki/linux
73937deb4b
restore_hv_regs() is used to copy the hv_regs L1 wants to set to run the nested (L2) guest into the vcpu structure. We need to sanitise these values to ensure we don't let the L1 guest hypervisor do things we don't want it to. We don't let data address watchpoints or completed instruction address breakpoints be set to match in hypervisor state. We also don't let L1 enable features in the hypervisor facility status and control register (HFSCR) for L2 which we have disabled for L1. That is L2 will get the subset of features which the L0 hypervisor has enabled for L1 and the features L1 wants to enable for L2. This could mean we give L1 a hypervisor facility unavailable interrupt for a facility it thinks it has enabled, however it shouldn't have enabled a facility it itself doesn't have for the L2 guest. We sanitise the registers when copying in the L2 hv_regs. We don't need to sanitise when copying back the L1 hv_regs since these shouldn't be able to contain invalid values as they're just what was copied out. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
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uapi/asm |