On Fri, Mar 29, 2024 at 12:02:00AM +1100, Michael Ellerman wrote: > The chacha-p10-crypto module provides optimised chacha routines for > Power10. It also selects CRYPTO_ARCH_HAVE_LIB_CHACHA which says it > provides chacha_crypt_arch() to generic code. > > Notably the module needs to provide chacha_crypt_arch() regardless of > whether it is loaded on Power10 or an older CPU. > > The implementation of chacha_crypt_arch() already has a fallback to > chacha_crypt_generic(), however the module as a whole fails to load on > pre-Power10, because of the use of module_cpu_feature_match(). > > This breaks for example loading wireguard: > > jostaberry-1:~ # modprobe -v wireguard > insmod > /lib/modules/6.8.0-lp155.8.g7e0e887-default/kernel/arch/powerpc/crypto/chacha-p10-crypto.ko.zst > modprobe: ERROR: could not insert 'wireguard': No such device > > Fix it by removing module_cpu_feature_match(), and instead check the > CPU feature manually. If the CPU feature is not found, the module > still loads successfully, but doesn't register the Power10 specific > algorithms. That allows chacha_crypt_generic() to remain available for > use, fixing the problem. > > [root@fedora ~]# modprobe -v wireguard > insmod /lib/modules/6.8.0-00001-g786a790c4d79/kernel/net/ipv4/udp_tunnel.ko > insmod > /lib/modules/6.8.0-00001-g786a790c4d79/kernel/net/ipv6/ip6_udp_tunnel.ko > insmod /lib/modules/6.8.0-00001-g786a790c4d79/kernel/lib/crypto/libchacha.ko > insmod > /lib/modules/6.8.0-00001-g786a790c4d79/kernel/arch/powerpc/crypto/chacha-p10-crypto.ko > insmod > /lib/modules/6.8.0-00001-g786a790c4d79/kernel/lib/crypto/libchacha20poly1305.ko > insmod > /lib/modules/6.8.0-00001-g786a790c4d79/kernel/drivers/net/wireguard/wireguard.ko > [ 18.910452][ T721] wireguard: allowedips self-tests: pass > [ 18.914999][ T721] wireguard: nonce counter self-tests: pass > [ 19.029066][ T721] wireguard: ratelimiter self-tests: pass > [ 19.029257][ T721] wireguard: WireGuard 1.0.0 loaded. See > www.wireguard.com for information. > [ 19.029361][ T721] wireguard: Copyright (C) 2015-2019 Jason A. > Donenfeld <ja...@zx2c4.com>. All Rights Reserved. > > Reported-by: Michal Suchánek <msucha...@suse.de> > Closes: https://lore.kernel.org/all/20240315122005.gg20...@kitsune.suse.cz/ > Signed-off-by: Michael Ellerman <m...@ellerman.id.au> > --- > arch/powerpc/crypto/chacha-p10-glue.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-)
Acked-by: Herbert Xu <herb...@gondor.apana.org.au> Thanks, -- Email: Herbert Xu <herb...@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt