On Thu, 16 Feb 2017 00:10:30 +0900 Masami Hiramatsu <[email protected]> wrote:
> On Fri, 10 Feb 2017 11:04:34 -0500 > Steven Rostedt <[email protected]> wrote: > > > On Fri, 10 Feb 2017 22:21:55 +0900 > > Masami Hiramatsu <[email protected]> wrote: > > > > > Since tracing/*probe_events will accept a probe definition > > > up to 4096 - 2 ('\n' and '\0') bytes, it must show 4094 instead > > > of 4096 in warning message. > > > > Actually, during the testing I found that we don't need the '\n'. > > > > echo -n 'p:irq do_IRQ a=@jiffies_64' > kprobe_events > > > > works just fine. My tests work with 4095 characters. Before and after > > my patch. > > Yeah, I see. I concider the case that if the writer writes > 4095 chars command + '\n' + next command, it will fail, that > is what I pointed out below note. > > > > > > > Note that there is one possible case of exceed 4094. If user > > > prepare 4096 bytes null-terminated string and syscall write > > > it with the count == 4095, then it can be accepted. However, > > > if user puts a '\n' after that, it must rejected. > > > So IMHO, the warning message should indicate shorter one, > > > since it is safer. > > Thank you, > OK, I'll just add the patch as is. Thanks, -- Steve
