From a4c331ce8c2378d98e0edfcdeedec308ef6ff163 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 7 Jan 2020 21:07:35 +0100 Subject: [PATCH] wireless: wext: avoid gcc -O3 warning After the introduction of CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3, the wext code produces a bogus warning: In function 'iw_handler_get_iwstats', inlined from 'ioctl_standard_call' at net/wireless/wext-core.c:1015:9, inlined from 'wireless_process_ioctl' at net/wireless/wext-core.c:935:10, inlined from 'wext_ioctl_dispatch.part.8' at net/wireless/wext-core.c:986:8, inlined from 'wext_handle_ioctl': net/wireless/wext-core.c:671:3: error: argument 1 null where non-null expected [-Werror=nonnull] memcpy(extra, stats, sizeof(struct iw_statistics)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from arch/x86/include/asm/string.h:5, net/wireless/wext-core.c: In function 'wext_handle_ioctl': arch/x86/include/asm/string_64.h:14:14: note: in a call to function 'memcpy' declared here The problem is that ioctl_standard_call() sometimes calls the handler with a NULL argument that would cause a problem for iw_handler_get_iwstats. However, iw_handler_get_iwstats never actually gets called that way. Marking that function as noinline avoids the warning and leads to slightly smaller object code as well. Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20200107200741.3588770-1-arnd@arndb.de Signed-off-by: Johannes Berg --- net/wireless/wext-core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/wireless/wext-core.c b/net/wireless/wext-core.c index 5e677dac2a0ce..69102fda9ebd4 100644 --- a/net/wireless/wext-core.c +++ b/net/wireless/wext-core.c @@ -657,7 +657,8 @@ struct iw_statistics *get_wireless_stats(struct net_device *dev) return NULL; } -static int iw_handler_get_iwstats(struct net_device * dev, +/* noinline to avoid a bogus warning with -O3 */ +static noinline int iw_handler_get_iwstats(struct net_device * dev, struct iw_request_info * info, union iwreq_data * wrqu, char * extra) -- 2.39.5