Re: [PATCH v2] checkpatch: Add a warning for log messages that don't end in a new line

From: Logan Gunthorpe
Date: Mon Nov 27 2017 - 12:07:22 EST




On 27/11/17 02:25 AM, Joe Perches wrote:
[]
diff -u -p a/lib/locking-selftest.c b/lib/locking-selftest.c
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -1186,7 +1186,7 @@ static void dotest(void (*testcase_fn)(v

static inline void print_testname(const char *testname)
{
- printk("%33s:", testname);
+ printk("%33s:\n", testname);
}

Coincidentally, the checkpatch script does not hit this false positive. This because a pr_cont actually follows in a #define. It doesn't feel right but checkpatch does do the correct thing on this one.

diff -u -p a/lib/dynamic_debug.c b/lib/dynamic_debug.c
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -562,7 +562,8 @@ void __dynamic_pr_debug(struct _ddebug *
vaf.fmt = fmt;
vaf.va = &args;

- printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf);
+ printk(KERN_DEBUG "%s%pV\n", dynamic_emit_prefix(descriptor, buf),
+ &vaf);

va_end(args);
}

This is a valid false positive that I also missed. However, it can actually be very easily ignored by checking if the format string ends in %pV. There were about 100 cases in my results that match this.


diff -u -p a/drivers/tty/serial/ioc4_serial.c b/drivers/tty/serial/ioc4_serial.c
--- a/drivers/tty/serial/ioc4_serial.c
+++ b/drivers/tty/serial/ioc4_serial.c
@@ -2858,8 +2858,7 @@ ioc4_serial_attach_one(struct ioc4_drive
"sgi-ioc4serial", soft)) {
control->ic_irq = idd->idd_pdev->irq;
} else {
- printk(KERN_WARNING
- "%s : request_irq fails for IRQ 0x%x\n ",
+ printk(KERN_WARNING "%s : request_irq fails for IRQ 0x%x\n \n",
__func__, idd->idd_pdev->irq);
}
ret = ioc4_attach_local(idd);

[]

This isn't an issue for the checkpatch script as it doesn't try to fix it, it only warns that it is wrong (as it is actually wrong).


diff -u -p a/drivers/isdn/gigaset/ev-layer.c b/drivers/isdn/gigaset/ev-layer.c
--- a/drivers/isdn/gigaset/ev-layer.c
+++ b/drivers/isdn/gigaset/ev-layer.c
@@ -411,7 +411,7 @@ static void add_cid_event(struct cardsta
unsigned next, tail;
struct event_t *event;

- gig_dbg(DEBUG_EVENT, "queueing event %d for cid %d", type, cid);
+ gig_dbg(DEBUG_EVENT, "queueing event %d for cid %d\n", type, cid);

spin_lock_irqsave(&cs->ev_lock, flags);

This is why I elected to only look at printk, pr_xxx, and dev_xxx in v2 of my patch. So this is another false positive the checkpatch script would not hit.


Logan