Commit 3e39c1ab04ba (printk: mark printk_once test variable __read_mostly) added __read_mostly to the __print_once bool in the printk_once() macro, but __read_mostly is defined in <linux/cache.h> which isn't included from <linux/printk.h>. This results in build errors like this: arch/metag/mm/l2cache.c: In function 'meta_l2c_setup': arch/metag/mm/l2cache.c:56: error: '__read_mostly' undeclared This is fixed by adding an include of <linux/cache.h> from <linux/printk.h> since I don't think printk_once() users should need to include <linux/cache.h> for it to work. Note that this actually adds a recursive include, since <linux/cache.h> includes <linux/kernel.h>, which includes <linux/printk.h>. The actual dependencies are all in macros so it doesn't actually seem to result in any build failures, but it's clearly less than ideal. Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx> Cc: Joe Perches <joe@xxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: linux-metag@xxxxxxxxxxxxxxx --- This build failure was caught in today's linux-next. I'm not too keen on this due to the recursive include. Is it better to just workaround the problem by including <linux/cache.h> from the .c file that fails to build, or should the original patch be removed instead? include/linux/printk.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/printk.h b/include/linux/printk.h index abd42dd..b13d00e 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -2,6 +2,7 @@ #define __KERNEL_PRINTK__ #include <stdarg.h> +#include <linux/cache.h> #include <linux/init.h> #include <linux/kern_levels.h> #include <linux/linkage.h> -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
