[J][PATCH v2 0/2] Long kernel command line on s390x (LP: 1960580)

frank.heimes at canonical.com frank.heimes at canonical.com
Thu Feb 17 19:02:45 UTC 2022


BugLink: https://bugs.launchpad.net/bugs/1960580

Allow to handle command lines with a length of up to 4096 bytes by kernel.
It happened in the past that our supported command line size of 896 bytes
was sometimes too short - while x86, powerpc, and arm each support 2048 bytes.

This requires:
 - an ABI interface to the kernel image, so that tools can figure out if the
   kernel supports large command lines (might be a feature bitmap at a fixed
   location)
 - zipl, genprotimg, qemu, kexec-tools and changes (depending on the kernel
   side implementation)
 - in-kernel ipl support changes (IPL from reader)

v2: converted 277c8389386e ("390/kexec_file: move kernel image size check")
    into a backport, due to required context adjustments

Sven Schnelle (2):
  s390/kexec_file: move kernel image size check
  s390: support command lines longer than 896 bytes

 arch/s390/boot/head.S                 | 37 +++++++++------------------
 arch/s390/boot/ipl_parm.c             |  4 +--
 arch/s390/include/asm/setup.h         |  8 +++---
 arch/s390/include/uapi/asm/setup.h    |  2 --
 arch/s390/kernel/asm-offsets.c        |  1 +
 arch/s390/kernel/early.c              |  2 +-
 arch/s390/kernel/machine_kexec_file.c | 35 +++++++++++++------------
 7 files changed, 39 insertions(+), 50 deletions(-)

-- 
2.25.1




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