[lkml]   [2014]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v2] n_tty: Fix read_buf race condition, increment read_head after pushing data
On Tue, Nov 11, 2014 at 2:04 PM, Måns Rullgård <> wrote:
> Christian Riesch <> writes:
[...]>> diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
>> index 2e900a9..b09f326 100644
>> --- a/drivers/tty/n_tty.c
>> +++ b/drivers/tty/n_tty.c
>> @@ -321,7 +321,9 @@ static void n_tty_check_unthrottle(struct tty_struct *tty)
>> static inline void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
>> {
>> - *read_buf_addr(ldata, ldata->read_head++) = c;
>> + *read_buf_addr(ldata, ldata->read_head) = c;
>> + /* increment read_head _after_ placing the character in the buffer */
>> + ldata->read_head++;
>> }
> Is that comment really necessary?

No, I am pretty sure that removing the comment would not break the code ;-)

I just thought it would be good to have some kind of reminder here.
Otherwise someone may think: Hey, it would be a good idea to do the
increment right in the first line. And submit a patch for it.
But I am also ok with removing the comment. So if you like me to post
a v3 without the comment, I'll be happy to do that.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2014-11-12 09:01    [W:0.050 / U:11.284 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site