]> Pileus Git - ~andy/linux/commit
[media] dvb-frontends: Don't use dynamic static allocation
authorMauro Carvalho Chehab <m.chehab@samsung.com>
Sat, 2 Nov 2013 08:05:18 +0000 (05:05 -0300)
committerMauro Carvalho Chehab <m.chehab@samsung.com>
Fri, 8 Nov 2013 11:45:38 +0000 (09:45 -0200)
commit8393796dfa4cf5dffcceec464c7789bec3a2f471
treef8410ce34146d3f4ef8bbcfb109328ea245c5574
parent9736a89dafe07359d9c86bf9c3b815a250b354bc
[media] dvb-frontends: Don't use dynamic static allocation

Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
drivers/media/dvb-frontends/bcm3510.c:230:1: warning: 'bcm3510_do_hab_cmd' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/itd1000.c:69:1: warning: 'itd1000_write_regs.constprop.0' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/mt312.c:126:1: warning: 'mt312_write' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/nxt200x.c:111:1: warning: 'nxt200x_writebytes' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/stb6100.c:216:1: warning: 'stb6100_write_reg_range.constprop.3' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/stv6110.c:98:1: warning: 'stv6110_write_regs' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/stv6110x.c:85:1: warning: 'stv6110x_write_regs' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/tda18271c2dd.c:147:1: warning: 'WriteRegs' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/zl10039.c:119:1: warning: 'zl10039_write' 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>
drivers/media/dvb-frontends/bcm3510.c
drivers/media/dvb-frontends/itd1000.c
drivers/media/dvb-frontends/mt312.c
drivers/media/dvb-frontends/nxt200x.c
drivers/media/dvb-frontends/stb6100.c
drivers/media/dvb-frontends/stv6110.c
drivers/media/dvb-frontends/stv6110x.c
drivers/media/dvb-frontends/tda18271c2dd.c
drivers/media/dvb-frontends/zl10039.c