Public bug reported:

https://github.com/golang/go/issues/46803
(https://go-review.googlesource.com/c/go/+/328110/)
This seems to be a somehow older issue, since we noticed this discussion on 
5.11:
https://lore.kernel.org/lkml/[email protected]/

Issue where the 5.13 kernel makes binaries built with Go before 1.15.15,
1.16.7, 1.17 prone to crashing when they receive a signal. The upstream
bug report is here https://github.com/golang/go/issues/46803 but the
issue is that the vDSO (virtual dynamic shared object) functions in 5.13
now touch r30 -- of course they preserve it, but before 5.13 they didn't
touch it at all and the Go runtime assumed that if a signal arrived
during a vDSO function the value it had stored in r30 was still valid.

We made sure that everything works on Impish and rebuilt all Go binaries - so 
impish (and newer) is be fine, because for impish we added the above kernel 
patch (the one discussed in the lkml) into 5.13.0-16.16 (in impish-proposed):
 fe57d86f7c3f ("powerpc/vdso: Don't use r30 to avoid breaking Go lang")
But we are still a bit concerned about older kernels / backports,
since this could be an issue with running older containers on newer hosts, and 
it potentially can be an issue for snaps, too.

** Affects: ubuntu-power-systems
     Importance: Undecided
     Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage)
         Status: Opinion

** Affects: golang (Ubuntu)
     Importance: Undecided
     Assignee: bugproxy (bugproxy)
         Status: Opinion

** Package changed: libpmemobj-cpp (Ubuntu) => golang (Ubuntu)

** Also affects: ubuntu-power-systems
   Importance: Undecided
       Status: New

** Changed in: ubuntu-power-systems
     Assignee: (unassigned) => Ubuntu on IBM Power Systems Bug Triage 
(ubuntu-power-triage)

** Changed in: golang (Ubuntu)
     Assignee: (unassigned) => bugproxy (bugproxy)

** Changed in: ubuntu-power-systems
       Status: New => Opinion

** Changed in: golang (Ubuntu)
       Status: New => Opinion

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https://bugs.launchpad.net/bugs/1943447

Title:
  Go runtime: ppc64x binaries randomly segfault on linux 5.13rc6
  (#46803)

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