User:Pietinger/Experimental/Manual Configuring Kernel Version 6.7

Note
Even though this page is in the user namespace, corrections and additions are much appreciated! This is simply wiki policy, this page can be moved to the main wiki as soon as it achieves critical mass ^more.

Manual Configuring Kernel Version 6.7

I wrote this article because some Gentoo users want try BCACHEFS which needs at least Linux kernel 6.7.

Upgrade from 6.6

If you do the make oldconfig there is only one question where you cannot simply accept the default via <return>:

AMD PCI USB host support (USB_PCI_AMD) [Y/n/?] (NEW)

Choose n here if you have an Intel CPU.

Because CONFIG_DEBUG_ENTRY was disabled by default in 6.6 you will get it again disabled. Please read on in the next but one chapter.

New Installation

Please configure according to the instructions of User:Pietinger/Tutorials/Manual_Configuring_Kernel_Version_6.6. But in 6.7. one option has been dropped: "AMD IOMMU Version 2 driver".

If you have an AMD, enable the following:

KERNEL Kernels 6.7

Device Drivers  --->
    [*] USB support  --->
        [*]     AMD PCI USB host support (NEW)

CONFIG_DEBUG_ENTRY

In the default configuration of 6.7 CONFIG_DEBUG_ENTRY is now enabled, while the help says: "This option enables sanity checks in x86's low-level entry code. Some of these sanity checks may slow down kernel entries and exits or otherwise impact performance. If unsure, say N". Please decide for yourself if you want to have it activated:

KERNEL Kernels 6.7

Kernel hacking  --->
    x86 Debugging  --->
        [?] Debug low-level entry code

Bcachefs

KERNEL Kernels 6.7 - Adding Bcachefs support

File Systems --->
   <*> bcachefs filesystem support (EXPERIMENTAL)
      [ ]   bcachefs quota support
      [ ]   bcachefs erasure coding (RAID5/6) support (EXPERIMENTAL)
      [*]   bcachefs POSIX ACL support
      [ ]   bcachefs runtime info
      [ ]   bcachefs debugging
      [ ]   bcachefs unit and performance tests
      [ ]   bcachefs lock time statistics
      [ ]   disable latency accounting and time stats

If a lscpu shows ssse3 and/or avx2 it is recommended to enable also:

KERNEL Adding Bcachefs support - Accelerated Cryptographic Algorithms

-*- Cryptographic API  --->
    Accelerated Cryptographic Algorithms for CPU (x86)  --->
        [*] Ciphers: ChaCha20, XChaCha20, XChaCha12 (SSSE3/AVX2/AVX-512VL)
        [*] Hash functions: Poly1305 (SSE2/AVX2)
        [*] Hash functions: SHA-224 and SHA-256 (SSSE3/AVX/AVX2/SHA-NI)
        [*] CRC32c (SSE4.2/PCLMULQDQ)