From: Tobias Klauser <tklauser@xxxxxxxxxx> Subject: fs/fs-writeback.c: adjust dirtytime_interval_handler definition to match prototype Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") changed ctl_table.proc_handler to take a kernel pointer. Adjust the definition of dirtytime_interval_handler to match its prototype in linux/writeback.h which fixes the following sparse error/warning: fs/fs-writeback.c:2189:50: warning: incorrect type in argument 3 (different address spaces) fs/fs-writeback.c:2189:50: expected void * fs/fs-writeback.c:2189:50: got void [noderef] __user *buffer fs/fs-writeback.c:2184:5: error: symbol 'dirtytime_interval_handler' redeclared with different type (incompatible argument 3 (different address spaces)): fs/fs-writeback.c:2184:5: int extern [addressable] [signed] [toplevel] dirtytime_interval_handler( ... ) fs/fs-writeback.c: note: in included file: ./include/linux/writeback.h:374:5: note: previously declared as: ./include/linux/writeback.h:374:5: int extern [addressable] [signed] [toplevel] dirtytime_interval_handler( ... ) Link: https://lkml.kernel.org/r/20200907093140.13434-1-tklauser@xxxxxxxxxx Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Signed-off-by: Tobias Klauser <tklauser@xxxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/fs-writeback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/fs-writeback.c~fs-adjust-dirtytime_interval_handler-definition-to-match-prototype +++ a/fs/fs-writeback.c @@ -2184,7 +2184,7 @@ static int __init start_dirtytime_writeb __initcall(start_dirtytime_writeback); int dirtytime_interval_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) + void *buffer, size_t *lenp, loff_t *ppos) { int ret; _