powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range

This patch makes sure we update the mmu_gather page size even if we are
requesting for a fullmm flush. This avoids triggering VM_WARN_ON in code
paths like __tlb_remove_page_size that explicitly check for removing range page
size to be same as mmu gather page size.

Fixes: 5a609934 ("powerpc/64s/radix: tlb do not flush on page size when fullmm")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/tlb.h

@@ -49,13 +49,11 @@ static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep,
 static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
 						     unsigned int page_size)
 {
-	if (tlb->fullmm)
-		return;
-
 	if (!tlb->page_size)
 		tlb->page_size = page_size;
 	else if (tlb->page_size != page_size) {
-		tlb_flush_mmu(tlb);
+		if (!tlb->fullmm)
+			tlb_flush_mmu(tlb);
 		/*
 		 * update the page size after flush for the new
 		 * mmu_gather.