1. 13 Apr, 2022 1 commit
    • Javier Martinez Canillas's avatar
      efi: Allow to enable EFI runtime services by default on RT · a031651f
      Javier Martinez Canillas authored
      Commit d9f283ae ("efi: Disable runtime services on RT") disabled EFI
      runtime services by default when the CONFIG_PREEMPT_RT option is enabled.
      
      The rationale for that commit is that some EFI calls could take too much
      time, leading to large latencies which is an issue for Real-Time kernels.
      
      But a side effect of that change was that now is not possible anymore to
      enable the EFI runtime services by default when CONFIG_PREEMPT_RT is set,
      without passing an efi=runtime command line parameter to the kernel.
      
      Instead, let's add a new EFI_DISABLE_RUNTIME boolean Kconfig option, that
      would be set to n by default but to y if CONFIG_PREEMPT_RT is enabled.
      
      That way, the current behaviour is preserved but gives users a mechanism
      to enable the EFI runtimes services in their kernels if that is required.
      For example, if the firmware could guarantee bounded time for EFI calls.
      
      Also, having a separate boolean config could allow users to disable the
      EFI runtime services by default even when CONFIG_PREEMPT_RT is not set.
      Reported-by: default avatarAlexander Larsson <alexl@redhat.com>
      Fixes: d9f283ae ("efi: Disable runtime services on RT")
      Signed-off-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
      Link: https://lore.kernel.org/r/20220331151654.184433-1-javierm@redhat.comSigned-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
      a031651f
  2. 03 Apr, 2022 8 commits
  3. 02 Apr, 2022 31 commits