db30144b5c
The pt_regs.trap field keeps 4 low bits for some metadata about the trap or how it was handled, which is masked off in order to test the architectural trap number. Add a set_trap() accessor to set this, equivalent to TRAP() for returning it. This is actually not quite the equivalent of TRAP() because it always clears the low bits, which may be harmless if it can only be updated via ptrace syscall, but it seems dangerous. In fact settting TRAP from ptrace doesn't seem like a great idea so maybe it's better deleted. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Make it a static inline rather than a shouty macro] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200507121332.2233629-2-mpe@ellerman.id.au
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.