A simple fix for a null pointer dereference in vmx_vcpu_run() with an ugly-but-safe prereq patch. The even uglier ASM_CALL_CONSTRAINT is gone in v2 as I finally figured out why vmx_return was undefined: GCC dropped the entire asm blob because all outputs were deemed unused. v2: - Document why there is no exact upstream commit for the fix, with --verbose. [Greg] - Tag the asm blob as volatile and drop the ASM_CALL_CONSTRAINT hack. Sean Christopherson (2): KVM: VMX: Explicitly reference RCX as the vmx_vcpu pointer in asm blobs KVM: VMX: Mark RCX, RDX and RSI as clobbered in vmx_vcpu_run()'s asm blob arch/x86/kvm/vmx.c | 91 +++++++++++++++++++++++++--------------------- 1 file changed, 50 insertions(+), 41 deletions(-) -- 2.26.0