On Fri, Oct 17, 2014 at 03:31:28PM +0200, Jiri Slaby wrote: > On 10/17/2014, 02:44 PM, Peter Hurley wrote: > > Hi Jiri, > > > > On 10/17/2014 04:46 AM, Jiri Slaby wrote: > >> On 10/16/2014, 10:54 PM, Peter Hurley wrote: > >>> Note the serial_struct flags for which the kernel ignores and performs > >>> no action. The flags cannot be removed since they form part of the > >>> userspace interface via the TIOCSSERIAL/TIOCGSERIAL ioctls. > >> > >> Hello, > >> > >> would it make sense to mark them deprecated somehow? At build time > > > > A build warning when the macro is expanded would be best, but my > > c-preprocessor-fu is terrible, so I have no idea how to make that work. > > We can define a deprecated type like: > > typedef __u32 __attribute__((deprecated)) depr_tty_t > > and then do define: > > #define ASYNCB_FLAG_1 (depr_tty_t)1 > #define ASYNCB_FLAG_2 (depr_tty_t)2 > > Etc. > > However, I do not know if it is desirable AND whether all compilers out > there used in userspace support that attribute. > > >> or > >> at least warn in the serial core that "current->comm is using a > >> deprecated flag"_ratelimited()? > > > > If we just print the message at TIOCSSERIAL if any of the deprecated > > bits are set, that would be ok. Probably the only issue would be that > > setserial could cause this message at will, so log flooding would be > > a concern. > > That's why _ratelimited(). So something like the patch attached. But it > needs to be put to a separate function, out of the line. > > /me currently builds a kernel to see who, if anybody, uses the flags on > a up-to-date system... What ever happened with this test? Care to resend it as a "real" patch so we can annoy userspace? :) thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
