On Tue, Sep 10, 2013 at 1:50 PM, Linus Torvalds <[email protected]> wrote: > Of course, maybe even the stupid add_device_randomness() is fast > enough. I just wanted to point out that it definitely isn't some > optimized thing.
When I posted the patch that mixes in the whole SMBIOS table: commit d114a33387472555188f142ed8e98acdb8181c6d Author: Tony Luck <[email protected]> Date: Fri Jul 20 13:15:20 2012 -0700 dmi: Feed DMI table to /dev/random driver I asked whether there was any size issue - as it tends to be a few kilobytes on laptops and desktops, and tens of kilobytes on servers. The answer I got back then was not to worry - digesting a few kilobytes wouldn't be a problem. I just threw in a debug message to check and saw: dmi_walk_early: added 10342 bytes in 339968 cycles So a couple of hundred microseconds for me. There are plenty of machine specific values buried in there (e.g. serial numbers for all the DIMMs) ... so this looks like a good use of this much boot time. -Tony -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
