On Mon, May 13, 2019 at 08:52:41AM +0000, David Laight wrote: > From: christophe leroy > > Sent: 10 May 2019 18:35 > > Le 10/05/2019 à 18:24, Steven Rostedt a écrit : > > > On Fri, 10 May 2019 10:42:13 +0200 > > > Petr Mladek <pmladek@xxxxxxxx> wrote: > > >> - if (probe_kernel_address(ptr, byte)) > > >> + if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) > > >> return "(efault)"; > > "efault" looks a bit like a spellling mistake for "default". It's a special, thus it's in parenthesis, though somebody can be misguided. > > Usually, < PAGE_SIZE means NULL pointer dereference (via the member of a > > struct) > > Maybe the caller should pass in a short buffer so that you can return > "(err-%d)" > or "(null+%#x)" ? In both cases it should be limited to the size of pointer (8 or 16 characters). Something like "(e:%4d)" would work for error codes. The "(null)" is good enough by itself and already an established practice.. -- With Best Regards, Andy Shevchenko
