Launching VM w/ AVIC disabled together with pass-through device
results in NULL pointer dereference bug with the following call trace.
RIP: 0010:svm_refresh_apicv_exec_ctrl+0x17e/0x1a0 [kvm_amd]
Call Trace:
kvm_vcpu_update_apicv+0x44/0x60 [kvm]
kvm_arch_vcpu_ioctl_run+0x3f4/0x1c80 [kvm]
kvm_vcpu_ioctl+0x3d8/0x650 [kvm]
do_vfs_ioctl+0xaa/0x660
? tomoyo_file_ioctl+0x19/0x20
ksys_ioctl+0x67/0x90
__x64_sys_ioctl+0x1a/0x20
do_syscall_64+0x57/0x190
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Investigation shows that this is due to the uninitialized usage of
struct vapu_svm.ir_list in the svm_set_pi_irte_mode(), which is
called from svm_refresh_apicv_exec_ctrl().
The ir_list is initialized only if AVIC is enabled. So, fixes by
adding a check if AVIC is enabled in the svm_refresh_apicv_exec_ctrl().
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206579
Fixes: 8937d76239 ("kvm: x86: svm: Add support to (de)activate posted interrupts.")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
93fd9666c2