1. 08 Mar, 2021 2 commits
    • Will Deacon's avatar
      arm64: Drop support for CMDLINE_EXTEND · cae118b6
      Will Deacon authored
      The documented behaviour for CMDLINE_EXTEND is that the arguments from
      the bootloader are appended to the built-in kernel command line. This
      also matches the option parsing behaviour for the EFI stub and early ID
      register overrides.
      
      Bizarrely, the fdt behaviour is the other way around: appending the
      built-in command line to the bootloader arguments, resulting in a
      command-line that doesn't necessarily line-up with the parsing order and
      definitely doesn't line-up with the documented behaviour.
      
      As it turns out, there is a proposal [1] to replace CMDLINE_EXTEND with
      CMDLINE_PREPEND and CMDLINE_APPEND options which should hopefully make
      the intended behaviour much clearer. While we wait for those to land,
      drop CMDLINE_EXTEND for now as there appears to be little enthusiasm for
      changing the current FDT behaviour.
      
      [1] https://lore.kernel.org/lkml/20190319232448.45964-2-danielwa@cisco.com/
      
      Cc: Max Uvarov <muvarov@gmail.com>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Ard Biesheuvel <ardb@kernel.org>
      Cc: Marc Zyngier <maz@kernel.org>
      Cc: Doug Anderson <dianders@chromium.org>
      Cc: Tyler Hicks <tyhicks@linux.microsoft.com>
      Cc: Frank Rowand <frowand.list@gmail.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Link: https://lore.kernel.org/r/CAL_JsqJX=TCCs7=gg486r9TN4NYscMTCLNfqJF9crskKPq-bTg@mail.gmail.com
      Link: https://lore.kernel.org/r/20210303134927.18975-3-will@kernel.orgSigned-off-by: default avatarWill Deacon <will@kernel.org>
      cae118b6
    • Will Deacon's avatar
      arm64: cpufeatures: Fix handling of CONFIG_CMDLINE for idreg overrides · df304c2d
      Will Deacon authored
      The built-in kernel commandline (CONFIG_CMDLINE) can be configured in
      three different ways:
      
        1. CMDLINE_FORCE: Use CONFIG_CMDLINE instead of any bootloader args
        2. CMDLINE_EXTEND: Append the bootloader args to CONFIG_CMDLINE
        3. CMDLINE_FROM_BOOTLOADER: Only use CONFIG_CMDLINE if there aren't
           any bootloader args.
      
      The early cmdline parsing to detect idreg overrides gets (2) and (3)
      slightly wrong: in the case of (2) the bootloader args are parsed first
      and in the case of (3) the CMDLINE is always parsed.
      
      Fix these issues by moving the bootargs parsing out into a helper
      function and following the same logic as that used by the EFI stub.
      Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
      Fixes: 33200303 ("arm64: cpufeature: Add an early command-line cpufeature override facility")
      Link: https://lore.kernel.org/r/20210303134927.18975-2-will@kernel.orgSigned-off-by: default avatarWill Deacon <will@kernel.org>
      df304c2d
  2. 06 Mar, 2021 4 commits
  3. 05 Mar, 2021 33 commits
  4. 04 Mar, 2021 1 commit
    • Jens Axboe's avatar
      kernel: provide create_io_thread() helper · cc440e87
      Jens Axboe authored
      Provide a generic helper for setting up an io_uring worker. Returns a
      task_struct so that the caller can do whatever setup is needed, then call
      wake_up_new_task() to kick it into gear.
      
      Add a kernel_clone_args member, io_thread, which tells copy_process() to
      mark the task with PF_IO_WORKER.
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      cc440e87