Message ID | 51DFE7D3.3090002@imgtec.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 7a58ab9..6a6a096 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1736,6 +1736,7 @@ endchoice config KVM_GUEST bool "KVM Guest Kernel" + depends on BROKEN_ON_SMP help Select this option if building a guest kernel for KVM (Trap & Emulate) mode
Make KVM_GUEST depend on BROKEN_ON_SMP so that it cannot be enabled with SMP. SMP kernels use ll/sc instructions for an atomic section in the tlb fill handler, with a tlbp instruction contained in the middle. This cannot be emulated with trap & emulate KVM because the tlbp instruction traps and the eret to return to the guest code clears the LLbit which makes the sc instruction always fail. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org --- arch/mips/Kconfig | 1 + 1 file changed, 1 insertion(+)