[PATCH] 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.

Signed-off-by: Aneesh Kumar K.V <redacted>
---
 arch/powerpc/include/asm/tlb.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/tlb.h b/arch/powerpc/include/asm/tlb.h
index 97ecef697e1b..f0e571b2dc7c 100644
--- a/arch/powerpc/include/asm/tlb.h
+++ b/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.

-- 
2.17.1

On Thu,  9 Aug 2018 19:06:59 +0530
"Aneesh Kumar K.V" [off-list ref] wrote:

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.

Signed-off-by: Aneesh Kumar K.V <redacted>

Acked-by: Nicholas Piggin <npiggin@gmail.com>

Thanks, sorry bout that.

"Aneesh Kumar K.V" [off-list ref] writes:

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.

I take it this is a fix for 5a6099346c41 ("powerpc/64s/radix: tlb do not flush on page size when fullmm") ?

cheers

On Thu, 2018-08-09 at 13:36:59 UTC, "Aneesh Kumar K.V" wrote:

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.

Signed-off-by: Aneesh Kumar K.V <redacted>
Acked-by: Nicholas Piggin <npiggin@gmail.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/0b6aa1a20add96437c46db77c9bae2

cheers