The -Wmaybe-uninitialized warning triggers for one driver using the output
of the 'insb' I/O helper on x86:
drivers/net/wireless/wl3501_cs.c: In function ‘wl3501_mgmt_scan_confirm’:
drivers/net/wireless/wl3501_cs.c:665:9: error: ‘sig.status’ is used uninitialized in this function [-Werror=uninitialized]
drivers/net/wireless/wl3501_cs.c:668:12: error: ‘sig.cap_info’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
Apparently the assember constraints are slightly off here, as marking the
'addr' argument as a memory output seems appropriate here and gets rid
of the warning. For consistency I'm also adding it as input for outsb().
Unfortunately, this fix triggers another problem when CONFIG_KASAN is
set, again only in this one driver:
drivers/net/wireless/wl3501_cs.c: In function 'wl3501_rx_interrupt':
drivers/net/wireless/wl3501_cs.c:1103:1: error: the frame size of 2232 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]
I'm not an x86 person and gcc inline assembly mystifies me all the time,
so please review this carefully and suggest a better way if this is not
how it should be done.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/x86/include/asm/io.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 7afb0e2f07f4..d107251eabd9 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -328,13 +328,13 @@ static inline unsigned type in##bwl##_p(int port) \
static inline void outs##bwl(int port, const void *addr, unsigned long count) \
{ \
asm volatile("rep; outs" #bwl \
- : "+S"(addr), "+c"(count) : "d"(port)); \
+ : "+S"(addr), "+c"(count) : "d"(port), "m" (addr));\
} \
\
static inline void ins##bwl(int port, void *addr, unsigned long count) \
{ \
asm volatile("rep; ins" #bwl \
- : "+D"(addr), "+c"(count) : "d"(port)); \
+ : "+D"(addr), "+c"(count), "=m" (addr) : "d"(port));\
}
BUILDIO(b, b, char)
--
2.9.0
