This is a note to let you know that I've just added the patch titled
powerpc/mm: Rearrange if-else block to avoid clang warning
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-mm-rearrange-if-else-block-to-avoid-clang-warning.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From d78c8e32890ef7eca79ffd67c96022c7f9d8cce4 Mon Sep 17 00:00:00 2001
From: Anders Roxell <anders.roxell@xxxxxxxxxx>
Date: Wed, 10 Aug 2022 13:43:18 +0200
Subject: powerpc/mm: Rearrange if-else block to avoid clang warning
From: Anders Roxell <anders.roxell@xxxxxxxxxx>
commit d78c8e32890ef7eca79ffd67c96022c7f9d8cce4 upstream.
Clang warns:
arch/powerpc/mm/book3s64/radix_tlb.c:1191:23: error: variable 'hstart' is uninitialized when used here
__tlbiel_va_range(hstart, hend, pid,
^~~~~~
arch/powerpc/mm/book3s64/radix_tlb.c:1191:31: error: variable 'hend' is uninitialized when used here
__tlbiel_va_range(hstart, hend, pid,
^~~~
Rework the 'if (IS_ENABLE(CONFIG_TRANSPARENT_HUGEPAGE))' so hstart/hend
is always initialized to 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@xxxxxxxx>
Suggested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220810114318.3220630-1-anders.roxell@xxxxxxxxxx
Signed-off-by: Daniel Díaz <daniel.diaz@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/mm/book3s64/radix_tlb.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index 50b70105364f..e50bc5fc7ddf 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -1184,15 +1184,12 @@ static inline void __radix__flush_tlb_range(struct mm_struct *mm,
}
}
} else {
- bool hflush = false;
+ bool hflush;
unsigned long hstart, hend;
- if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
- hstart = (start + PMD_SIZE - 1) & PMD_MASK;
- hend = end & PMD_MASK;
- if (hstart < hend)
- hflush = true;
- }
+ hstart = (start + PMD_SIZE - 1) & PMD_MASK;
+ hend = end & PMD_MASK;
+ hflush = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hstart < hend;
if (type == FLUSH_TYPE_LOCAL) {
asm volatile("ptesync": : :"memory");
--
2.39.2
Patches currently in stable-queue which might be from anders.roxell@xxxxxxxxxx are
queue-4.19/powerpc-mm-rearrange-if-else-block-to-avoid-clang-warning.patch
