media: stv0367: Don't use dynamic static allocation
authorMauro Carvalho Chehab <m.chehab@samsung.com>
Sat, 2 Nov 2013 08:17:01 +0000 (05:17 -0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 4 Dec 2013 18:57:33 +0000 (10:57 -0800)
commit6d3ac5e79294ecf2c437de63e9a38d125b7c5922
treec8d582694554368ac0074b35cd9c54d0b4c6fa87
parentbea929cb3ef0887cccf8e30331574f23f530ba99
media: stv0367: Don't use dynamic static allocation

commit 9aca4fb0571ce9cfef680ceb08d19dd008015307 upstream.

Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
drivers/media/dvb-frontends/stv0367.c:791:1: warning: 'stv0367_writeregs.constprop.4' uses dynamic stack allocation [enabled by default]
Instead, let's enforce a limit for the buffer. Considering that I2C
transfers are generally limited, and that devices used on USB has a
max data length of 64 bytes for the control URBs.
So, it seem safe to use 64 bytes as the hard limit for all those devices.
 On most cases, the limit is a way lower than that, but this limit
is small enough to not affect the Kernel stack, and it is a no brain
limit, as using smaller ones would require to either carefully each
driver or to take a look on each datasheet.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/media/dvb-frontends/stv0367.c