Just one fix, to make sure the PCR (Processor Compatibility Register) is reset
on boot. Otherwise if we're running in compat mode in a guest (eg. pretending a
Power9 is a Power8) and the host kernel oopses and kdumps then the kdump
kernel's userspace will be running in Power8 mode, and will SIGILL if it uses
Power9-only instructions.
Thanks to:
Michael Neuling.
-----BEGIN PGP SIGNATURE-----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=lmT9
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"Just one fix, to make sure the PCR (Processor Compatibility Register)
is reset on boot.
Otherwise if we're running in compat mode in a guest (eg. pretending a
Power9 is a Power8) and the host kernel oopses and kdumps then the
kdump kernel's userspace will be running in Power8 mode, and will
SIGILL if it uses Power9-only instructions.
Thanks to Michael Neuling"
* tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Clear PCR on boot
b133ef6ea4