On (20/05/20 21:40), Andrew Morton wrote:
> > On (20/05/20 18:00), Andrew Morton wrote:
> > [..]
> > > I'm wondering if we shold add a kernel puts() (putsk()? yuk) which can
> > > puts() a string of any length.
> > >
> > > I'm counting around 150 instances of printk("%s", ...) and pr_foo("%s",
> > > ...) which could perhaps be converted, thus saving an argument.
> >
> > Can you point me at some examples?
> >
>
> ./arch/powerpc/kernel/udbg.c: printk("%s", s);
> ./arch/powerpc/xmon/nonstdio.c: printk("%s", xmon_outbuf);
> ./arch/um/os-Linux/drivers/ethertap_user.c: printk("%s", output);
> ./arch/um/os-Linux/drivers/ethertap_user.c: printk("%s", output);
> ./arch/um/os-Linux/drivers/tuntap_user.c: printk("%s",
> out
Hmm, interesting.
output = uml_kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
read_output(fd, output, UM_KERN_PAGE_SIZE);
printk("%s", output);
kfree(output);
> etc.
>
> My point is, if we created a length-unlimited puts() function for printing the
> kernel command line, it could be reused in such places
A function that prints the kernel command line is a bit different
in the way that we can split command line arguments - they are
space separated, which is very convenient - so we would pr_cont()
parts of command line individually. This has an advantage that we
won't \r\n in the middle of the parameter.
Looking at examples, it seems that most of them simply do a single
printk() with arbitrary sized buffers that contain random data,
not necessarily space separated. So same problem - we truncate
messages (maybe?), but needs a slightly different solution (?).
-ss
