On Fri, 28 Jan 2022 at 11:14, Christophe Leroy
[off-list ref] wrote:

Le 28/01/2022 à 11:08, Anders Roxell a écrit :

quoted

Clang warns:

arch/powerpc/mm/book3s64/radix_tlb.c:1191:23: error: variable 'hstart' is uninitialized when used here [-Werror,-Wuninitialized]
                                 __tlbiel_va_range(hstart, hend, pid,
                                                   ^~~~~~
arch/powerpc/mm/book3s64/radix_tlb.c:1175:23: note: initialize the variable 'hstart' to silence this warning
                 unsigned long hstart, hend;
                                     ^
                                      = 0
arch/powerpc/mm/book3s64/radix_tlb.c:1191:31: error: variable 'hend' is uninitialized when used here [-Werror,-Wuninitialized]
                                 __tlbiel_va_range(hstart, hend, pid,
                                                           ^~~~
arch/powerpc/mm/book3s64/radix_tlb.c:1175:29: note: initialize the variable 'hend' to silence this warning
                 unsigned long hstart, hend;
                                           ^
                                            = 0
2 errors generated.

Rework the 'if (IS_ENABLE(CONFIG_TRANSPARENT_HUGEPAGE))' so hstart/hend
always gets initialized, this will silence the warnings. That will also
simplify the 'else' path. Clang is getting confused with these warnings,
but the warnings is a false-positive.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Anders Roxell <redacted>
---
  arch/powerpc/mm/book3s64/radix_tlb.c | 9 +++------
  1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index 7724af19ed7e..7d65965a0688 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c

@@ -1174,12 +1174,9 @@ static inline void __radix__flush_tlb_range(struct mm_struct *mm,
              bool hflush = false;

You should then remove the default initialisation of hflush to false
which has become pointless.

With that fixed,

Reviewed-by: Christophe Leroy <redacted>

Thank you for the review.
I will send a v3 shortly with that fixed.

Cheers,
Anders