forked from Minki/linux
f7af5209b8
In existing real mode ICP code, when updating the virtual ICP state, if there is a required action that cannot be completely handled in real mode, as for instance, a VCPU needs to be woken up, flags are set in the ICP to indicate the required action. This is checked when returning from hypercalls to decide whether the call needs switch back to the host where the action can be performed in virtual mode. Note that if h_ipi_redirect is enabled, real mode code will first try to message a free host CPU to complete this job instead of returning the host to do it ourselves. Currently, the real mode PCI passthrough interrupt handling code checks if any of these flags are set and simply returns to the host. This is not good enough as the trap value (0x500) is treated as an external interrupt by the host code. It is only when the trap value is a hypercall that the host code searches for and acts on unfinished work by calling kvmppc_xics_rm_complete. This patch introduces a special trap BOOK3S_INTERRUPT_HV_RM_HARD which is returned by KVM if there is unfinished business to be completed in host virtual mode after handling a PCI passthrough interrupt. The host checks for this special interrupt condition and calls into the kvmppc_xics_rm_complete, which is made an exported function for this reason. [paulus@ozlabs.org - moved logic to set r12 to BOOK3S_INTERRUPT_HV_RM_HARD in book3s_hv_rmhandlers.S into the end of kvmppc_check_wake_reason.] Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> |
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uapi/asm |