Pkg xen devel - Mar 2023 - Bug#1032480: xen: Important cherry-picks for bookworm/updates

Package: src:xen
Version: 4.17.0+46-gaaf74a532c-1
Severity: important

Two major bugs have shown with the release of new hardware from AMD.
Since the new hardware is likely to become common during the life of
Debian/bookworm, you may wish to grab them early:

ad15a0a8ca2515d8ac58edfc0bc1d3719219cb77
x86/time: prevent overflow with high frequency TSCs

Turns out the latest generation is fast enough to cause overflows.



I haven't found a patch for the other one yet.  There is some issue with
the latest generation which needs "x2apic=false" on Xen's
command-line
in order to get interrupts to domain 0.  I'm guessing the latest from AMD
broke the PIC emulation.

If this isn't actually patched yet, I suspect it soon will be.  I
haven't
observed anything on xen-devel, so perhaps the workaround was found too
quickly to get noticed as urgent.


Now to continuing the work on figuring out the consequences from
upgrading hardware a bit too early...


-- 
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On Tue, Mar 07, 2023 at 01:13:56PM -0800, Elliott Mitchell
wrote:
> 
> ad15a0a8ca2515d8ac58edfc0bc1d3719219cb77
> x86/time: prevent overflow with high frequency TSCs
Okay, looks like this one had already been grabbed.  Sorry for the way
too late alert.  Thanks for staying on top of what was happening with
upstream Xen.

> I haven't found a patch for the other one yet.  There is some issue
with
> the latest generation which needs "x2apic=false" on Xen's
command-line
> in order to get interrupts to domain 0.  I'm guessing the latest from
AMD
> broke the PIC emulation.
> 
> If this isn't actually patched yet, I suspect it soon will be.  I
haven't
> observed anything on xen-devel, so perhaps the workaround was found too
> quickly to get noticed as urgent.
This one though looks potentially more and less serious.  The workaround
is simpler than the above ("x2apic=false" on Xen's command-line,
instead
of "tsc_mode = 1" for *every* VM).  Yet the underlying problem could
be
more severe.


-- 
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  \_CS\   |  _____  -O #include <stddisclaimer.h> O-   _____  |   /  _/
8A19\___\_|_/58D2 7E3D DDF4 7BA6 <-PGP-> 41D1 B375 37D0 8714\_|_/___/5445

Your message dated Sun, 30 Jul 2023 17:53:45 -0700
with message-id <ZMcGGcZy1LPIJ7yG at mattapan.m5p.com>
and subject line Close #1032480
has caused the Debian Bug report #1032480,
regarding xen: Important cherry-picks for bookworm/updates
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner at bugs.debian.org
immediately.)


-- 
1032480: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1032480
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems
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