• Petr Mladek's avatar
    printk: split code for making free space in the log buffer · 0a581694
    Petr Mladek authored
    The check for free space in the log buffer always passes when "first_seq"
    and "next_seq" are equal.  In theory, it might cause writing outside of
    the log buffer.
    
    Fortunately, the current usage looks safe because the used "text" and
    "dict" buffers are quite limited.  See the second patch for more details.
    
    Anyway, it is better to be on the safe side and add a check.  An easy
    solution is done in the 2nd patch and it is improved in the 4th patch.
    
    5th patch fixes the computation of the printed message length.
    
    1st and 3rd patches just do some code refactoring to make the other
    patches easier.
    
    This patch (of 5):
    
    There will be needed some fixes in the check for free space.  They will be
    easier if the code is moved outside of the quite long log_store()
    function.
    
    This patch does not change the existing behavior.
    Signed-off-by: default avatarPetr Mladek <pmladek@suse.cz>
    Cc: Jan Kara <jack@suse.cz>
    Cc: Jiri Kosina <jkosina@suse.cz>
    Cc: Kay Sievers <kay@vrfy.org>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    0a581694
printk.c 72.6 KB