commit 1005bccd7a4a ("crypto: caam - enable instantiation of all RNG4 state handles") introduces a control when incrementing ent_delay which contains the following comment above it:
/* * If either SH were instantiated by somebody else * (e.g. u-boot) then it is assumed that the entropy * parameters are properly set and thus the function * setting these (kick_trng(...)) is skipped. * Also, if a handle was instantiated, do not change * the TRNG parameters. */ The problem is if u-boot has already instantiated the RNG and TEE/OPTEE is running then instantiate_rng() will always return -EAGAIN and ent_delay will never increment causing the loop to never break. This patch fixes commit 1005bccd7a4a ("crypto: caam - enable instantiation of all RNG4 state handles") by always incrementing ent_delay if and only if both rng4_sh_init and inst_handles are non-zero for a given loop. This should allow the current behavior to continue while allowing the loop to break should (rng4_sh_init=1 && inst_handles 1) be true and instantiate_rng() return -EAGAIN forever. Fixes: 1005bccd7a4a ("crypto: caam - enable instantiation of all RNG4 state handles") Reported-by: Ryan Harkin <ryan.har...@linaro.org> Signed-off-by: Bryan O'Donoghue <pure.lo...@nexus-software.ie> Cc: "Horia Geantă" <horia.gea...@nxp.com> Cc: Aymen Sghaier <aymen.sgha...@nxp.com> Cc: Fabio Estevam <fabio.este...@nxp.com> Cc: Peng Fan <peng....@nxp.com> Cc: Herbert Xu <herb...@gondor.apana.org.au> Cc: "David S. Miller" <da...@davemloft.net> Cc: Lukas Auer <lukas.a...@aisec.fraunhofer.de> --- drivers/crypto/caam/ctrl.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c index 98986d3..0a1e96b 100644 --- a/drivers/crypto/caam/ctrl.c +++ b/drivers/crypto/caam/ctrl.c @@ -704,7 +704,10 @@ static int caam_probe(struct platform_device *pdev) ent_delay); kick_trng(pdev, ent_delay); ent_delay += 400; + } else if (ctrlpriv->rng4_sh_init && inst_handles) { + ent_delay += 400; } + /* * if instantiate_rng(...) fails, the loop will rerun * and the kick_trng(...) function will modfiy the -- 2.7.4