[Pkg-xen-devel] Bug#900746: xen toolstack xl causes a Segmentation fault on create domu

[Damian Pietras]

I've also hit it on one of my boxes with
4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u8

This is related to too small stack size set for threads in XEN utils
which explicitly set it to use 16KB. Similar issue is reported here for
NTP: https://bugzilla.redhat.com/show_bug.cgi?id=1564527

I've recompilled the package with the attached patch to increase the
stack size from 16KB to 32KB and it works.

Technical details:

The issue appears with modern CPU that support AVX-512 instruction set,
in my case it's Intel(R) Xeon(R) Gold 6148. More details are in this
bug report against glibc: https://bugzilla.redhat.com/show_bug.cgi?id=1
527887#c18

There was a post on xen-users acknowledging the bug that says it's
fixed in XEN 4.11: https://lists.xenproject.org/archives/html/xen-users
/2018-05/msg00034.html





-- 
Damian Pietras
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