lkml.org 
[lkml]   [2019]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] x86, random: Fix get_random_bytes() warning in x86 start_kernel
On Sun, Feb 03, 2019 at 08:09:37AM -0500, Prarit Bhargava wrote:
> Ted, the bug I'm trying to fix is the warning:
>
> random: get_random_bytes called from start_kernel+0x8e/0x587 with crng_init=0
>
> during early boot. Even with the kernel parameter the warning appears.

Sometimes the warnings are real, and shouldn't be suppressed. A
Debian maintainer once tried to suppress a compile-time warning, and
it was disastrous for security. :-)

What line number is that corresponding to? It sounds like something
is trying to use get_random_bytes() before the random driver was
initialized, and so the first question is does it really need to call
get_random_bytes() then or can it be moved?

> > Also, relying on the TSC for entropy is not something we should be
> > recommending.
>
> The current code uses the TSC. It is not something new I'm introducing.

But we don't *rely* on it. That's a big difference.

- Ted

\
 
 \ /
  Last update: 2019-02-04 16:56    [W:0.170 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site