14369 2021-04-29 07:07:23 +0000 rng-tools: rngd hang when use jitter entropy with internal timer 2021-11-09 02:14:21 +0000 1 1 7 Build System, Metadata & Runtime OE-Core oe-core other 3.3 x86 Multiple RESOLVED FIXED backport Medium+ normal 3.4 M4 1 mingli.yu mingli.yu JPEWhacker randy.macleod --- --- No (bug/feature does not impact docs) oldest_to_newest 90151 0 mingli.yu 2021-04-29 07:07:23 +0000 The rngd hang when the board only has jitter entropy and also coarse resolution timer. And the issue can be reproduced in any board when force to use the internal timer as below: 1, apply below patch for libjitterentropy recipe which rng-tools depends(this pach force to use the internal timer). $ git diff diff --git a/jitterentropy-base.c b/jitterentropy-base.c index 6dbb484..07397cb 100644 --- a/jitterentropy-base.c +++ b/jitterentropy-base.c @@ -1387,7 +1387,8 @@ int jent_entropy_init(void) if (sha3_tester()) return EHASH; - ret = jent_time_entropy_init(0); + //ret = jent_time_entropy_init(0); + ret = 1; #ifdef JENT_CONF_ENABLE_INTERNAL_TIMER jent_force_internal_timer = 0; 2, use the jitter entropy as below: rngd -f -x hwrng -x rdrand 90168 1 randy.macleod 2021-04-29 15:18:48 +0000 We are following the general kernel security/ rngd recommendations. There are other sources of entropy such as virt-io. maybe we should be using haveved? 90200 2 mingli.yu 2021-04-30 02:04:50 +0000 (In reply to comment #1) > We are following the general kernel security/ rngd recommendations. > There are other sources of entropy such as virt-io. > > maybe we should be using haveved? The bug against the jitter entropy source, such as on the borad nxp-s32g2xx, we only have the jitter entropy source and also need to use the internal timer as the coarse resolution timer. 90201 3 mingli.yu 2021-04-30 02:05:32 +0000 The bug against the jitter entropy source, such as on the borad nxp-s32g2xx, we only have the jitter entropy source and also need to use the internal timer as the coarse resolution timer. 90267 4 randy.macleod 2021-05-06 14:35:13 +0000 Mingli, Please work with the upstream developers to figure out how to deal with the behaviour on this board. 90269 5 randy.macleod 2021-05-06 14:36:09 +0000 Again: We are following the general kernel security/ rngd recommendations. There are other sources of entropy such as virt-io. maybe we should be using haveved? 90377 6 randy.macleod 2021-05-13 15:33:36 +0000 We're talking about this on the oe-core email list. 91915 7 mingli.yu 2021-11-09 02:14:21 +0000 https://git.openembedded.org/openembedded-core/commit/?id=ea06a05bf00ffc004184faa93a41deee84105f8a https://git.openembedded.org/openembedded-core/commit/?id=28b3d8c01966d16f8ab8d61beaf9527f987f1ec6