Although there was some discussion http://thread.gmane.org/gmane.linux.kernel/680723
about removing IRQF_SAMPLE_RANDOM from the remaining network drivers in May of 2008, but they still appears to be there in 2.6.29.
drivers/net/ibmlana.c
drivers/net/macb.c
drivers/net/3c523.c
drivers/net/3c527.c
drivers/net/netxen/netxen_nic_main.c
drivers/net/cris/eth_v10.c
drivers/net/xen-netfront.c
drivers/net/atlx/atl1.c
drivers/net/qla3xxx.c
drivers/net/tg3.c
drivers/net/niu.c
So what is the plan? If I send a patch to add IRQF_SAMPLE_RANDOM to others (like the Blackfin) networking drivers - will it get rejected?
We have lots of embedded headless systems (no keyboard/mouse, no soundcard, no video) systems with *no* sources of entropy - and people using SSL.
I didn't really find any docs which describe what should have IRQF_SAMPLE_RANDOM on it or not. I did find Matt Mackall describing it as:We currently assume that IRQF_SAMPLE_RANDOM means 'this is a completely
trusted unobservable entropy source' which is obviously wrong for
network devices but is right for some other classes of device.
Currently - I see most things I see using IRQF_SAMPLE_RANDOM would also fail the "completely unobservable" test. Other than the TRNG that are inside the CPU - what does pass?