On Thu, Jul 5, 2018 at 1:29 AM, Johannes Thumshirn <jthumshirn@xxxxxxx> wrote: > On Wed, Jul 04, 2018 at 11:50:13PM -0700, Dan Williams wrote: >> +static ssize_t memmap_state_store(struct device *dev, >> + struct device_attribute *attr, const char *buf, size_t len) >> +{ >> + int i; >> + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); >> + struct memmap_async_state *async = &nd_pfn->async; >> + >> + if (strcmp(buf, "sync") == 0) >> + /* pass */; >> + else if (strcmp(buf, "sync\n") == 0) >> + /* pass */; >> + else >> + return -EINVAL; > > Hmm what about: > > if (strncmp(buf, "sync", 4)) > return -EINVAL; > > This collapses 6 lines into 4. ...but that also allows 'echo "syncAndThenSomeGarbage" > /sys/.../memmap_state' to succeed.