diff options
Diffstat (limited to 'pkgs')
| -rw-r--r-- | pkgs/os-specific/linux/kernel/common-config.nix | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/pkgs/os-specific/linux/kernel/common-config.nix b/pkgs/os-specific/linux/kernel/common-config.nix index 4e366a87d09..fb583551f1b 100644 --- a/pkgs/os-specific/linux/kernel/common-config.nix +++ b/pkgs/os-specific/linux/kernel/common-config.nix @@ -1007,6 +1007,28 @@ let # Keeping it a built-in ensures it will be used if possible. FB_SIMPLE = yes; + # https://docs.kernel.org/arch/arm/mem_alignment.html + # tldr: + # when buggy userspace code emits illegal misaligned LDM, STM, + # LDRD and STRDs, the instructions trap, are caught, and then + # are emulated by the kernel. + # + # This is the default on armv7l, anyway, but it is explicitly + # enabled here for the sake of providing context for the + # aarch64 compat option which follows. + ALIGNMENT_TRAP = mkIf (stdenv.hostPlatform.system == "armv7l-linux") yes; + + # https://patchwork.kernel.org/project/linux-arm-kernel/patch/20220701135322.3025321-1-ardb@kernel.org/ + # tldr: + # when encountering alignment faults under aarch64, this option + # makes the kernel attempt to handle the fault by doing the + # same style of misaligned emulation that is performed under + # armv7l (see above option). + # + # This minimizes the potential for aarch32 userspace to behave + # differently when run under aarch64 kernels compared to when + # it is run under an aarch32 kernel. + COMPAT_ALIGNMENT_FIXUPS = mkIf (stdenv.hostPlatform.system == "aarch64-linux") (whenAtLeast "6.1" yes); } // optionalAttrs (versionAtLeast version "5.4" && (stdenv.hostPlatform.system == "x86_64-linux" || stdenv.hostPlatform.system == "aarch64-linux")) { # Required for various hardware features on Chrome OS devices CHROME_PLATFORMS = yes; |