[tor-bugs] #24500 [Core Tor/Tor]: Confusing log message "Can't get entropy from getrandom()"

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#24500: Confusing log message "Can't get entropy from getrandom()"
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 Reporter:  arma          |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  Medium        |      Milestone:
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Comment (by yawning):

 If you knew that their kernel was ancient, you should have mentioned it
 when filing the bug...

 Ubuntu 16.04 LTS ships with Linux 4.4
 (https://wiki.ubuntu.com/XenialXerus/ReleaseNotes#Linux_kernel_4.4).

 Per comment:7:ticket:24164
 >  Im running Ubuntu 16.04.3 LTS (GNU/Linux 2.6.32-042stab120.11 x86_64)
 and I still get the errors on Tor 0.3.2.5-alpha

 This is most certainly a `ENOSYS`, due to their OpenVZ kernel, which is
 not the kernel shipped by the the version of Ubuntu listed in this bug
 report.

 > What should the relay operator do?

 Ignore the message.  It happens once and only once per launch.  The log
 message could be more informative, and still probably should log errno,
 but apart from that I think it's fine as is.

 I'm personally in favor of leaving this as a `warn`, as `getrandom()`
 support is common place, and falling back to `/dev/urandom` is objectively
 a bad thing.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/24500#comment:3>
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