Bug#990462: Bug#990319: unblock: intel-microcode/3.20210608.2

[Justin B Rye <justin.byam.rye@gmail.com>]

Paul Gevers wrote:
>> We could replace this with "See the instructions in the DSA (also in
>> the intel-microcode README.Debian)".  Mind you, it would be nice if
>> that README started with "TLDR: boot with dis_ucode_ldr"!
> 
> To get this straight, you only propose to replace the piece between
> brackets (inclusive) with that right? I think it's worth saying "you can
> recover".

Yes, though I was vaguely thinking that in the process of adding
markup we might reorganise the links, since we don't need full URLs in
the text.  Something like

   <section id="intel-microcode">
     <!-- buster to bullseye -->
     <title>Intel CPU microcode issues</title>
     <para>
       The <systemitem role="package">intel-microcode</systemitem> package
       currently in bullseye and buster-security (see <ulink
       url="https://www.debian.org/security/2021/dsa-4934";>DSA-4934-1</ulink>)
       is known to contain two significant bugs. For some CoffeeLake CPUs this
       update <ulink
       url="https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/issues/56";>may
       break network interfaces</ulink> that use <systemitem
       role="package">firmware-iwlwifi</systemitem>, and for some Skylake
       R0/D0 CPUs on systems using a very outdated firmware/BIOS, <ulink
       url="https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/issues/31";>the
       system may hang on boot</ulink>.
     </para>
     <para>
       If you held back the update from DSA-4934-1 due to either of these
       issues, or do not have the security archive enabled, be aware that
       upgrading to the <systemitem
       role="package">intel-microcode</systemitem> package in bullseye may
       cause your system to hang on boot or break iwlwifi. In that case, you
       can recover by disabling microcode loading on boot; see the
       instructions in the DSA, which are also in the <systemitem
       role="package">intel-microcode</systemitem>
       <filename>README.Debian</filename>.
     </para>
   </section>

(When it says "currently in bullseye and buster-security", are there
plans for this to change?  If not, drop the "currently"; if so, we
have to remember to update the release notes when it happens.)
-- 
JBR	with qualifications in linguistics, experience as a Debian
	sysadmin, and probably no clue about this particular package