da9ed30d29
The startup code is getting more complicated with features like kaslr and secure boot in place. In a potential unexpected startup code crash case the system would end up in a pgm check loop at address 0, overwriting pgm check old psw value and just making debugging more complicated. To avoid that introduce startup program check handler which is active immediately after kernel start and until early_pgm_check_handler is set in kernel/early.c. So it covers kernel relocation phase and transition to it. This pgm check handler simply saves general/control registers and psw in the save area which should guarantee that we still have something to look at when standalone dumper is called without saving registers. And it does disabled wait with a faulty address in the end. Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.