- turn the stack canary into a normal __percpu variable on 32-bit which
gets rid of the LAZY_GS stuff and a lot of code.

- Add an insn_decode() API which all users of the instruction decoder
should preferrably use. Its goal is to keep the details of the
instruction decoder away from its users and simplify and streamline how
one decodes insns in the kernel. Convert its users to it.

- kprobes improvements and fixes

- Set the maximum DIE per package variable on Hygon

- Rip out the dynamic NOP selection and simplify all the machinery around
selecting NOPs. Use the simplified NOPs in objtool now too.

- Add Xeon Sapphire Rapids to list of CPUs that support PPIN

- Simplify the retpolines by folding the entire thing into an
alternative now that objtool can handle alternatives with stack
ops. Then, have objtool rewrite the call to the retpoline with the
alternative which then will get patched at boot time.

- Document Intel uarch per models in intel-family.h

- Make Sub-NUMA Clustering topology the default and Cluster-on-Die the
exception on Intel.
x86, sched: Treat Intel SNC topology as default, COD as exception

Commit 1340ccfa9a9a ("x86,sched: Allow topologies where NUMA nodes
share an LLC") added a vendor and model specific check to never
call topology_sane() for Intel Skylake Server systems where NUMA
nodes share an LLC.

Intel Ice Lake and Sapphire Rapids CPUs also enumerate an LLC that is
shared by multiple NUMA nodes. The LLC on these CPUs is shared for
off-package data access but private to the NUMA node for on-package
access. Rather than managing a list of allowable SNC topologies, make
this SNC topology the default, and treat Intel's Cluster-On-Die (COD)
topology as the exception.

In SNC mode, Sky Lake, Ice Lake, and Sapphire Rapids servers do not
emit this warning:

sched: CPU #3's llc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20210310190233.31752-1-alison.schofield@intel.com
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