Change default page table size to 4

Start by inspecting the arm64 kernel configuration and the CONFIG_PGTABLE_LEVELS entry, then reproduce the failure with docker run --rm envoyproxy/envoy:v1.17.0 --version on the reported Raspberry Pi setup. Determine whether changing the default to 4 preserves supported page configurations; done means the kernel builds and Envoy starts without the tcmalloc allocation error.

Describe the bug
Google's tcmalloc assumes a page table size of 4 (which seems to be considered the default) to allocate heap and fails since the kernel is compiled with CONFIG_PGTABLE_LEVELS=3 by default.

To reproduce
As example you could try to run the envoy proxy which uses tcmalloc under the hood.
docker run --rm envoyproxy/envoy:v1.17.0 --version
This will fail with a memory allocation error.

Expected behaviour
The heap allocation should not fail and enovy should print its version information. This can be achieved by setting CONFIG_PGTABLE_LEVELS=4.

Actual behaviour
The heap allocation fails leading to envoy not being able start up and fail with an error message.

System

Raspberry Pi 4 Model B Rev 1.4
PRETTY_NAME="Debian GNU/Linux 10 (buster)"
NAME="Debian GNU/Linux"
VERSION_ID="10"
VERSION="10 (buster)"

Raspberry Pi reference 2020-08-20
Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 7252c154838ec5b4576f29c996ac8fe3750cae12, stage2

Linux raspberrypi-4 5.10.17-v8+ #1421 SMP PREEMPT Thu May 27 14:01:37 BST 2021 aarch64 GNU/Linux
Revision	: d03114
Model		: Raspberry Pi 4 Model B Rev 1.4
Throttled flag  : throttled=0x0
Camera          : supported=0 detected=0

version 7d9a298cda813f747b51fe17e1e417e7bf5ca94d (clean) (release) (start)

Logs
This is the error message you will receive from envoy / tcmalloc when kernel is compiled with CONFIG_PGTABLE_LEVELS=3:

external/com_github_google_tcmalloc/tcmalloc/system-alloc.cc:550] MmapAligned() failed (size, alignment) 1073741824 1073741824 @ 0x55867b9470 0x55867aba14 0x55867ab454 0x5586794e94 0x55867a8684
external/com_github_google_tcmalloc/tcmalloc/arena.cc:34] FATAL ERROR: Out of memory trying to allocate internal tcmalloc data (bytes, object-size) 131072 48 @ 0x55867b9780 0x5586794f10 0x55867a8684

Additional context
This is a conversation from the OpenJDK project which had to deal with the same situation: http://openjdk.5641.n7.nabble.com/ZGC-aarch64-Unable-to-allocate-heap-for-certain-Linux-kernel-configurations-td420728.html
Basically their solution is to try allocating memory multiple times until it succeeds, which does not seem to be ideal.

This is the excerpt from the kernel documentation:

AArch64 Linux uses either 3 levels or 4 levels of translation tables
with the 4KB page configuration, allowing 39-bit (512GB) or 48-bit
(256TB) virtual addresses, respectively, for both user and kernel. With
64KB pages, only 2 levels of translation tables, allowing 42-bit (4TB)
virtual address, are used but the memory layout is the same.

These are the open issues for envoy and tcmalloc