Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDave Jones <davej@redhat.com>

Split trivial #if defined(__KERNEL__) && X conditionals to make automated
disintegration easier.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

This change adds support for /proc/sys/debug/exception-trace to tile.
Like x86 and sparc, by default it is set to "1", generating a one-line
printk whenever a user process crashes.  By setting it to "2", we get
a much more complete userspace diagnostic at crash time, including
a user-space backtrace, register dump, and memory dump around the
address of the crash.

Some vestiges of the Tilera-internal version of this support are
removed with this patch (the show_crashinfo variable and the
arch_coredump_signal function).  We retain a "crashinfo" boot parameter
which allows you to set the boot-time value of exception-trace.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>

The current tile rt_sigreturn() syscall pattern uses the common idiom
of loading up pt_regs with all the saved registers from the time of
the signal, then anticipating the fact that we will clobber the ABI
"return value" register (r0) as we return from the syscall by setting
the rt_sigreturn return value to whatever random value was in the pt_regs
for r0.

However, this breaks in our 64-bit kernel when running "compat" tasks,
since we always sign-extend the "return value" register to properly
handle returned pointers that are in the upper 2GB of the 32-bit compat
address space.  Doing this to the sigreturn path then causes occasional
random corruption of the 64-bit r0 register.

Instead, we stop doing the crazy "load the return-value register"
hack in sigreturn.  We already have some sigreturn-specific assembly
code that we use to pass the pt_regs pointer to C code.  We extend that
code to also set the link register to point to a spot a few instructions
after the usual syscall return address so we don't clobber the saved r0.
Now it no longer matters what the rt_sigreturn syscall returns, and the
pt_regs structure can be cleanly and completely reloaded.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>

Rather than just using pt_regs, it now contains the actual saved
state explicitly, similar to pt_regs.  By doing it this way, we
provide a cleaner API for userspace (or equivalently, we avoid the
need for libc to provide its own definition of sigcontext).

While we're at it, move PT_FLAGS_xxx to where they are not visible
from userspace.  And always pass siginfo and mcontext to signal
handlers, even if they claim they don't need it, since sometimes
they actually try to use it anyway in practice.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>

This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read.  Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:

- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
  also avoid partial-line printks except in bootup code.
  - checkpatch: Use exposed structs rather than typedefs.
  - checkpatch: Change some C99 comments to C89 comments.

In addition, a couple of minor other changes are rolled in
to this commit:

- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
  some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.

This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: NPaul Mundt <lethal@linux-sh.org>