Update the __flush_tlb_range_op macro not to modify its parameters as
these are unexepcted semantics. In practice, this fixes the call to
mmu_notifier_arch_invalidate_secondary_tlbs() in
__flush_tlb_range_nosync() to use the correct range instead of an empty
range with start=end. The empty range was (un)lucky as it results in
taking the invalidate-all path that doesn't cause correctness issues,
but can certainly result in suboptimal perf.
This has been broken since commit 6bbd42e2df8f ("mmu_notifiers: call
invalidate_range() when invalidating TLBs") when the call to the
notifiers was added to __flush_tlb_range(). It predates the addition of
the __flush_tlb_range_op() macro from commit 360839027a6e ("arm64: tlb:
Refactor the core flush algorithm of __flush_tlb_range") that made the
bug hard to spot.
Fixes: 6bbd42e2df8f ("mmu_notifiers: call invalidate_range() when invalidating TLBs")
Signed-off-by: Piotr Jaroszynski <pjaroszynski@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Raghavendra Rao Ananta <rananta@xxxxxxxxxx>
Cc: SeongJae Park <sj@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Nicolin Chen <nicolinc@xxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: iommu@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
---
arch/arm64/include/asm/tlbflush.h | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index bc94e036a26b..8104aee4f9a0 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -396,33 +396,35 @@ static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
#define __flush_tlb_range_op(op, start, pages, stride, \
asid, tlb_level, tlbi_user, lpa2) \
do { \
+ typeof(start) __flush_start = start; \
+ typeof(pages) __flush_pages = pages; \
int num = 0; \
int scale = 3; \
int shift = lpa2 ? 16 : PAGE_SHIFT; \
unsigned long addr; \
\
- while (pages > 0) { \
+ while (__flush_pages > 0) { \
if (!system_supports_tlb_range() || \
- pages == 1 || \
- (lpa2 && start != ALIGN(start, SZ_64K))) { \
- addr = __TLBI_VADDR(start, asid); \
+ __flush_pages == 1 || \
+ (lpa2 && __flush_start != ALIGN(__flush_start, SZ_64K))) { \
+ addr = __TLBI_VADDR(__flush_start, asid); \
__tlbi_level(op, addr, tlb_level); \
if (tlbi_user) \
__tlbi_user_level(op, addr, tlb_level); \
- start += stride; \
- pages -= stride >> PAGE_SHIFT; \
+ __flush_start += stride; \
+ __flush_pages -= stride >> PAGE_SHIFT; \
continue; \
} \
\
- num = __TLBI_RANGE_NUM(pages, scale); \
+ num = __TLBI_RANGE_NUM(__flush_pages, scale); \
if (num >= 0) { \
- addr = __TLBI_VADDR_RANGE(start >> shift, asid, \
+ addr = __TLBI_VADDR_RANGE(__flush_start >> shift, asid, \
scale, num, tlb_level); \
__tlbi(r##op, addr); \
if (tlbi_user) \
__tlbi_user(r##op, addr); \
- start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \
- pages -= __TLBI_RANGE_PAGES(num, scale); \
+ __flush_start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \
+ __flush_pages -= __TLBI_RANGE_PAGES(num, scale);\
} \
scale--; \
} \
base-commit: 99fa936e8e4f117d62f229003c9799686f74cebc
--
2.22.1.7.gac84d6e93c.dirty
