4e0e45b07d
It's not very nice to zero trap for this, because then system calls no longer have trap_is_syscall(regs) invariant, and we can't distinguish between sc and scv system calls (in a later patch). Take one last unused bit from the low bits of the pt_regs.trap word for this instead. There is not a really good reason why it should be in trap as opposed to another field, but trap has some concept of flags and it exists. Ideally I think we would move trap to 2-byte field and have 2 more bytes available independently. Add a selftests case for this, which can be seen to fail if trap_norestart() is changed to return false. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Make them static inlines] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200507121332.2233629-4-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.