On Tue, May 07, 2019 at 01:50:29PM +0200, Petr Mladek wrote: > On Mon 2019-05-06 19:43:19, Josh Poimboeuf wrote: > > On Tue, Apr 30, 2019 at 11:10:49AM +0200, Petr Mladek wrote: > > > klp_try_switch_task() is called under klp_mutex. The buffer for > > > debugging messages might be static. > > > > The patch description is missing a "why" (presumably to reduce stack > > usage). > > Exactly. I thought that it was obvious. But I am infected by printk > code where line buffers are 1k and nobody wants them on the stack. > > 128bytes in klp_try_switch_task() context are acceptable but > it is still rather big buffer. > > OK, what about the following commit message? > > "klp_try_switch_task() is called under klp_mutex. The buffer for > debugging messages might be static to reduce stack usage." It's better to use imperative language. It would also be good to reverse the order of the wording by starting with the problem. Something like: The err_buf array uses 128 bytes of stack space. Move it off the stack by making it static. It's safe to use a shared buffer because klp_try_switch_task() is called under klp_mutex. -- Josh
