On 12/6/18 3:24 PM, John Nielsen wrote: >> On Dec 6, 2018, at 4:04 PM, Xin LI <delp...@gmail.com> wrote: >> >> On Thu, Dec 6, 2018 at 11:37 AM John Nielsen <li...@jnielsen.net> wrote: >>> >>> I have upgraded two physical machines from 11-STABLE to 12-STABLE recently >>> (one is 12.0-PRERELEASE r341380 and the other is 12.0-PRERELEASE r341391). >>> I noticed today that neither machine seems to be utilizing /dev/crypto. >>> Typically I see at least ssh/sshd have the device open plus some programs >>> from ports. But 'fuser' doesn't list any processes on either machine: >>> >>> # fuser /dev/crypto >>> /dev/crypto: >>> >>> Both machines are running custom kernels that include "device crypto" and >>> "device cryptodev". One of them additionally has "device aesni". >>> >>> Is anyone else seeing this? Any idea what would cause it? >> >> Your average OpenSSL applications should not use /dev/crypto, if your >> goal is to utilize AES-NI (which does not require /dev/crypto). On >> capable systems, AES-NI would be used automatically (and it's faster >> this way). > > Thanks for the response. Is there a way to verify that AES-NI is being used > for e.g. ssh? I'm also curious why/when/how the change to not use (or > support?) /dev/crypto from base openssl was made.
I suspect it was something we just didn't test in the flurry of other work during the OpenSSL upgrade. However, it is much faster to use the AES-NI instructions in userland than to use a system call that copies the data into a kernel buffer, uses the sames AES-NI instructions, then copies the data back out again along with the overhead of a pair of user <--> kernel transitions. If you have an actual crypto offload device (as in a PCI-e card or something), then you might be interested in /dev/crypto (and we should fix that eventually), but AES-NI is just faster software crypto and is best done directly in userland. -- John Baldwin _______________________________________________ freebsd-stable@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
