Re: [PATCH] Kbuild: Disable the -Wformat-security gcc flag

On Tue, Feb 10, 2009 at 10:11 PM, Kyle Moffett <kyle@xxxxxxxxxxxxxxx> wrote:
On Thu, Feb 5, 2009 at 3:26 AM, Floris Kraak <randakar@xxxxxxxxx> wrote:
There are probably some real bugs in there. On the other hand there is
some overhead to fixing the warnings. Kernel text size increase,
possibly some CPU overhead from parsing the format string. Hopefully
none of these calls are in really hot code paths ;-)

Actually, I would really suspect that CPU time would *decrease* for
most of these, because instead of groveling through the whole argument
string looking for '%' symbols we would do a single "%s" lookup
followed by a basic strncpy(dmesg_buffer + offset, arg,
dmesg_buffer_size - offset);


True enough.
Still increasing kernel text in a number of cases.

I've been thinking that in a lot of them (most of the 'banner' and
'version' substitutions, basically) I can probably get away with
moving the string argument into the function that uses it without
losing the __initdata section advantage - it just gets moved from an
__initdata segment into an __init declared function anyway.. or
something that should be declared __init at any rate since what the
hell is it using __initdata segment data for otherwise?

Unless some expert on these section markers can dispute that line of
reasoning, anyway ;-)
It means redoing most - possibly all - of the trivial patch though.

Getting rid if a few warnings most people don't even get is more work
than I thought. And to think I was considering looking into other
types of warnings as well ..
I should consider it a nice exercise in learning kernel development
practices I guess ..

Regards,
Floris
---
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deserve neither liberty nor safety."
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"The course of history shows that as a government grows, liberty
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