CVE-2026-64165: ARM: integrator: Fix early initialization

In the Linux kernel, the following vulnerability has been resolved:

ARM: integrator: Fix early initialization

Starting with commit bdb249fce9ad4 ("ARM: integrator: read counter using syscon/regmap"), intcpinitearly calls sysconregmaplookupbycompatible which in turn calls ofsysconregister. This function allocates memory. Since the memory management code has not been initialized at that time, the call always fails. It either returns -ENOMEM or crashes as follows.

Unable to handle kernel NULL pointer dereference at virtual address 0000000c when read [0000000c] pgd=00000000 Internal error: Oops: 5 [#1] ARM Modules linked in: CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.15.0-rc5-00026-g5fcc9bf84ee5 #1 PREEMPT Hardware name: ARM Integrator/CP (Device Tree) PC is at kmalloccachenoprof+0xec/0x39c LR is at kmalloccachenoprof+0x34/0x39c ... Call trace: kmalloccachenoprof from ofsysconregister+0x7c/0x310 ofsysconregister from devicenodegetregmap+0xa4/0xb0 devicenodegetregmap from intcpinitearly+0xc/0x40 intcpinitearly from startkernel+0x60/0x688 startkernel from 0x0

The crash is seen due to a dereferenced pointer which is not supposed to be NULL but is NULL if the memory management subsystem has not been initialized. The crash is not seen with all versions of gcc. Some versions such as gcc 9.x apparently do not dereference the pointer, presumably if tracing is disabled. The problem has been reproduced with gcc 10.x, 11.x, and 13.x. Either case, if the crash is not seen, the call to sysconregmaplookupbycompatible returns -ENOMEM, and schedclockregister is never called.

Fix the problem by moving the early initialization code into the standard machine initialization code.