On Thu, 11 Jun 2020 17:31:59 +0530, Aneesh Kumar K.V wrote:

__pa() do check for addr value passed and if < PAGE_OFFSET
results in BUG.

 #define __pa(x)								\
({									\
	VIRTUAL_BUG_ON((unsigned long)(x) < PAGE_OFFSET);		\
	(unsigned long)(x) & 0x0fffffffffffffffUL;			\
})

[...]

Applied to powerpc/fixes.

[1/1] powerpc/kvm/book3s64: Fix kernel crash with nested kvm & DEBUG_VIRTUAL
      https://git.kernel.org/powerpc/c/c1ed1754f271f6b7acb1bfdc8cfb62220fbed423

cheers