dracut icon indicating copy to clipboard operation
dracut copied to clipboard

[Enhancement] Support adding ACPI tables to early cpio archive for microcode patching

Open nagmat84 opened this issue 10 months ago • 0 comments

This enhancement ask to add an option to include patched ACPI tables into the early CPIO archive which Dracut currently already creates for microcode update.

Some BIOS/(U)EFI firmware report buggy ACPI tables to the operating system. The Linux kernel supports overriding those ACPI tables with a patched ACPI table very early in the boot process. The patched ACPI tables must be included in an uncompressed, early CPIO archive at the location /kernel/firmware/acpi/<name of table>.aml (see Kernel Documentation: Override ACPI Tables). This CPIO archive must be loaded by the kernel before any "actual" initramfs. In this respect, this early CPIO archive isn't much different from the CPIO archive for CPU microcode patching, it can even be the same.

An enhancement could looks as follows:

  1. Add a new command line option --acpi-tables <directory> or configuration option include_acpi_tables=<directory>
  2. When Dracut builds the early CPIO archive for microcode CPU updates, Dracut copies any *.aml file which it find in that directory into /kernel/firmware/acpi/ of the early CPIO archive.

nagmat84 avatar Dec 13 '24 12:12 nagmat84