On Tue, Feb 23, 2021 at 11:50 AM Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:
If CONFIG_DEBUG_SG=y, and CONFIG_MMU=y:
include/linux/scatterlist.h: In function ‘sg_set_buf’:
arch/m68k/include/asm/page_mm.h:174:49: warning: ordered comparison of pointer with null pointer [-Wextra]
174 | #define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory)
| ^~
or CONFIG_MMU=n:
include/linux/scatterlist.h: In function ‘sg_set_buf’:
arch/m68k/include/asm/page_no.h:33:50: warning: ordered comparison of pointer with null pointer [-Wextra]
33 | #define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
| ^~
Fix this by doing the comparison in the "unsigned long" instead of the
"void *" domain.
Note that for now this is only seen when compiling btrfs, due to commit
e9aa7c285d20a69c ("btrfs: enable W=1 checks for btrfs"), but as people
are doing more W=1 compile testing, it will start to show up elsewhere,
too.
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
Probably we want this as a fix for v5.12, to avoid the build bots
nagging about it all the time?
arch/m68k/include/asm/page_mm.h | 2 +-
arch/m68k/include/asm/page_no.h | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/m68k/include/asm/page_mm.h b/arch/m68k/include/asm/page_mm.h
index 7f5912af2a52ea0a..9b1672f9b2e22cdf 100644
--- a/arch/m68k/include/asm/page_mm.h
+++ b/arch/m68k/include/asm/page_mm.h
@@ -171,7 +171,7 @@ static inline __attribute_const__ int __virt_to_node_shift(void)
#include <asm-generic/memory_model.h>
#endif
-#define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory)
+#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && ((unsigned long)kaddr) < (unsigned long)high_memory)
While preparing the pull request, I noticed I misplaced the braces in
the second part.
Will send a v2...
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
