commit a61674bdfc7c2bf909c4010699607b62b69b7bec upstream.

GCC 6 will include changes to generated code with -mcmodel=large,
which is used to build kernel modules on powerpc64le.  This was
necessary because the large model is supposed to allow arbitrary
sizes and locations of the code and data sections, but the ELFv2
global entry point prolog still made the unconditional assumption
that the TOC associated with any particular function can be found
within 2 GB of the function entry point:

func:
	addis r2,r12,(.TOC.-func)@ha
	addi  r2,r2,(.TOC.-func)@l
	.localentry func, .-func

To remove this assumption, GCC will now generate instead this global
entry point prolog sequence when using -mcmodel=large:

	.quad .TOC.-func
func:
	.reloc ., R_PPC64_ENTRY
	ld    r2, -8(r12)
	add   r2, r2, r12
	.localentry func, .-func

The new .reloc triggers an optimization in the linker that will
replace this new prolog with the original code (see above) if the
linker determines that the distance between .TOC. and func is in
range after all.

Since this new relocation is now present in module object files,
the kernel module loader is required to handle them too.  This
patch adds support for the new relocation and implements the
same optimization done by the GNU linker.

Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The selftest passes on 64-bit LE & BE, and 32-bit.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The selftest passes on 64-bit LE and BE.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This adds include/uapi/asm/eeh.h to kbuild so that the header
file will be exported automatically with below command. The
header file was added by commit ed3e81ff2016 ("powerpc/eeh: Move PE
state constants around")

   make INSTALL_HDR_PATH=/tmp/headers \
        SRCARCH=powerpc headers_install

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently on powerpc we have our own #define for the highest (negative)
errno value, called _LAST_ERRNO. This is defined to be 516, for reasons
which are not clear.

The generic code, and x86, use MAX_ERRNO, which is defined to be 4095.

In particular seccomp uses MAX_ERRNO to restrict the value that a
seccomp filter can return.

Currently with the mismatch between _LAST_ERRNO and MAX_ERRNO, a seccomp
tracer wanting to return 600, expecting it to be seen as an error, would
instead find on powerpc that userspace sees a successful syscall with a
return value of 600.

To avoid this inconsistency, switch powerpc to use MAX_ERRNO.

We are somewhat confident that generic syscalls that can return a
non-error value above negative MAX_ERRNO have already been updated to
use force_successful_syscall_return().

I have also checked all the powerpc specific syscalls, and believe that
none of them expect to return a non-error value between -MAX_ERRNO and
-516. So this change should be safe ...

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Kees Cook <keescook@chromium.org>

Commit ce48b2100785 "powerpc: Add VSX context save/restore, ptrace and
signal support" expanded the 'vmx_reserve' array element to contain 101
double words, but the comment block above was not updated.

Also reorder the constants in the array size declaration to reflect the
logic mentioned in the comment block above. This change helps in
explaining how the HW registers are represented in the array. But no
functional change.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
[mpe: Reworded change log and added whitespace around +'s]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch changes the syscall handler to doom (tabort) active
transactions when a syscall is made and return very early without
performing the syscall and keeping side effects to a minimum (no CPU
accounting or system call tracing is performed). Also included is a
new HWCAP2 bit, PPC_FEATURE2_HTM_NOSC, to indicate this
behaviour to userspace.

Currently, the system call instruction automatically suspends an
active transaction which causes side effects to persist when an active
transaction fails.

This does change the kernel's behaviour, but in a way that was
documented as unsupported.  It doesn't reduce functionality as
syscalls will still be performed after tsuspend; it just requires that
the transaction be explicitly suspended.  It also provides a
consistent interface and makes the behaviour of user code
substantially the same across powerpc and platforms that do not
support suspended transactions (e.g. x86 and s390).

Performance measurements using
http://ozlabs.org/~anton/junkcode/null_syscall.c indicate the cost of
a normal (non-aborted) system call increases by about 0.25%.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We'll want to build the opal-prd daemon with the prd headers, so include
this in the uapi headers list.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This change adds a char device to access the "PRD" (processor runtime
diagnostics) channel to OPAL firmware.

Includes contributions from Vaidyanathan Srinivasan, Neelesh Gupta &
Vishal Kulkarni.

Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The patch defines PCI error types and functions in uapi/asm/eeh.h
and exports function eeh_pe_inject_err(), which will be called by
VFIO driver to inject the specified PCI error to the indicated
PE for testing purpose.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>