The PPC_DT_CPU_FTRs is a bit misplaced in menuconfig, it shows up with
other general kernel options. It's really more at home in the "Platform
Support" section, so move it there.

Also enable it by default, for Book3s 64. It does mostly nothing unless
the device tree properties are found, and we will want it enabled
eventually in distro kernels, so turn it on to start getting more
testing.

Fixes: 5a61ef74 ("powerpc/64s: Support new device tree binding for discovering CPU features")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Provide a dt_cpu_ftrs= cmdline option to disable the dt_cpu_ftrs CPU
feature discovery, and fall back to the "cputable" based version.

Also allow control of advertising unknown features to userspace and
with this parameter, and remove the clunky CONFIG option.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
[mpe: Add explicit early check of bootargs in dt_cpu_ftrs_init()]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The ibm,powerpc-cpu-features device tree binding describes CPU features with
ASCII names and extensible compatibility, privilege, and enablement metadata
that allows improved flexibility and compatibility with new hardware.

The interface is described in detail in ibm,powerpc-cpu-features.txt in this
patch.

Currently this code is not enabled by default, and there are no released
firmwares that provide the binding.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that crashkernel parameter parsing and vmcoreinfo related code is
moved under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE, remove
dependency with CONFIG_KEXEC for CONFIG_FA_DUMP.  While here, get rid of
definitions of fadump_append_elf_note() & fadump_final_note() functions
to reuse similar functions compiled under CONFIG_CRASH_CORE.

Link: http://lkml.kernel.org/r/149035343956.6881.1536459326017709354.stgit@hbathini.in.ibm.comSigned-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: NMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This was a hack we added to work around the allmodconfig build breaking, see
commit fb43e847 ("powerpc: Disable RELOCATABLE for COMPILE_TEST with
PPC64").

Since we merged the thin archives support in commit 43c9127d ("powerpc: Add
option to use thin archives") this hasn't been necessary, so remove it.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Add a simple NMI IPI system that handles concurrency and reentrancy.

The platform does not have to implement a true non-maskable interrupt,
the default is to simply use the debugger break IPI message. This has
now been co-opted for a general IPI message, and users (debugger and
crash) have been reimplemented on top of the NMI system.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
[mpe: Incorporate incremental fixes from Nick]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all architectures converted
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Allow kprobes to be placed on ftrace _mcount() call sites. This optimization
avoids the use of a trap, by riding on ftrace infrastructure.

This depends on HAVE_DYNAMIC_FTRACE_WITH_REGS which depends on MPROFILE_KERNEL,
which is only currently enabled on powerpc64le with newer toolchains.

Based on the x86 code by Masami.
Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This reverts commit 2947ba05.

Dan Williams reported dax-pmem kernel warnings with the following signature:

   WARNING: CPU: 8 PID: 245 at lib/percpu-refcount.c:155 percpu_ref_switch_to_atomic_rcu+0x1f5/0x200
   percpu ref (dax_pmem_percpu_release [dax_pmem]) <= 0 (0) after switching to atomic

... and bisected it to this commit, which suggests possible memory corruption
caused by the x86 fast-GUP conversion.

He also pointed out:

 "
  This is similar to the backtrace when we were not properly handling
  pud faults and was fixed with this commit: 220ced16 "mm: fix
  get_user_pages() vs device-dax pud mappings"

  I've found some missing _devmap checks in the generic
  get_user_pages_fast() path, but this does not fix the regression
  [...]
 "

So given that there are known bugs, and a pretty robust looking bisection
points to this commit suggesting that are unknown bugs in the conversion
as well, revert it for the time being - we'll re-try in v4.13.
Reported-by: NDan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: aneesh.kumar@linux.vnet.ibm.com
Cc: dann.frazier@canonical.com
Cc: dave.hansen@intel.com
Cc: steve.capper@linaro.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Add powerpc support for mmap_rnd_bits and mmap_rnd_compat_bits, which are two
sysctls that allow a user to configure the number of bits of randomness used for
ASLR.

Because of the way the Kconfig for ARCH_MMAP_RND_BITS is defined, we have to
construct at least the MIN value in Kconfig, vs in a header which would be more
natural. Given that we just go ahead and do it all in Kconfig.

At least according to the code (the documentation makes no mention of it), the
value is defined as the number of bits of randomisation *of the page*, not the
address. This makes some sense, with larger page sizes more of the low bits are
forced to zero, which would reduce the randomisation if we didn't take the
PAGE_SIZE into account. However it does mean the min/max values have to change
depending on the PAGE_SIZE in order to actually limit the amount of address
space consumed by the randomisation.

The result of that is that we have to define the default values based on both
32-bit vs 64-bit, but also the configured PAGE_SIZE. Furthermore now that we
have 128TB address space support on Book3S, we also have to take that into
account.

Finally we can wire up the value in arch_mmap_rnd().
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBhupesh Sharma <bhsharma@redhat.com>
Tested-by: NBhupesh Sharma <bhsharma@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

The definition of smp_mb__after_unlock_lock() is currently smp_mb()
for CONFIG_PPC and a no-op otherwise.  It would be better to instead
provide an architecture-selectable Kconfig option, and select the
strength of smp_mb__after_unlock_lock() based on that option.  This
commit therefore creates ARCH_WEAK_RELEASE_ACQUIRE, has PPC select it,
and bases the definition of smp_mb__after_unlock_lock() on this new
ARCH_WEAK_RELEASE_ACQUIRE Kconfig option.
Reported-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Boqun Feng <boqun.feng@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Cc: <linuxppc-dev@lists.ozlabs.org>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Make sparsemem the default on all 64-bit Book3S platforms. It already is
for pseries and ps3, and we need to enable it for powernv because on
POWER9 memory between chips is discontiguous.

For the other platforms sparsemem should work fine, though it might add
a small amount of overhead. We can always force FLATMEM in the
defconfigs if necessary.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Shift the logic for defining THREAD_SHIFT logic to Kconfig in order to
allow override by users.
Signed-off-by: NHamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: NChris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch provides all required callbacks required by the generic
get_user_pages_fast() code and switches x86 over - and removes
the platform specific implementation.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316213906.89528-1-kirill.shutemov@linux.intel.com
[ Minor readability edits. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We have a big list of selects under CONFIG_PPC, and currently they're
completely unsorted. This means people tend to add new selects at the
bottom of the list, and so two commits which both add a new select will
often conflict.

Instead sort it alphabetically. This is nicer in and of itself, but also
means two commits that add a new select will have a greater chance of
not conflicting.

Add a note at the top and bottom asking people to keep it sorted.

And while we're here pad out the 'if' expressions to make them stand
out.
Suggested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The final paragraph of the help text is reversed. We want to enable
this option by default, and disable it if the toolchain has a working
-mprofile-kernel.

Fixes: 8c50b72a ("powerpc/ftrace: Add Kconfig & Make glue for mprofile-kernel")
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Current infrastructure of kprobe uses the unconditional trap instruction
to probe a running kernel. Optprobe allows kprobe to replace the trap
with a branch instruction to a detour buffer. Detour buffer contains
instructions to create an in memory pt_regs. Detour buffer also has a
call to optimized_callback() which in turn call the pre_handler(). After
the execution of the pre-handler, a call is made for instruction
emulation. The NIP is determined in advanced through dummy instruction
emulation and a branch instruction is created to the NIP at the end of
the trampoline.

To address the limitation of branch instruction in POWER architecture,
detour buffer slot is allocated from a reserved area. For the time
being, 64KB is reserved in memory for this purpose.

Instructions which can be emulated using analyse_instr() are the
candidates for optimization. Before optimization ensure that the address
range between the detour buffer allocated and the instruction being
probed is within +/- 32MB.
Signed-off-by: NAnju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The modversion symbol CRCs are emitted as ELF symbols, which allows us
to easily populate the kcrctab sections by relying on the linker to
associate each kcrctab slot with the correct value.

This has a couple of downsides:

 - Given that the CRCs are treated as memory addresses, we waste 4 bytes
   for each CRC on 64 bit architectures,

 - On architectures that support runtime relocation, a R_<arch>_RELATIVE
   relocation entry is emitted for each CRC value, which identifies it
   as a quantity that requires fixing up based on the actual runtime
   load offset of the kernel. This results in corrupted CRCs unless we
   explicitly undo the fixup (and this is currently being handled in the
   core module code)

 - Such runtime relocation entries take up 24 bytes of __init space
   each, resulting in a x8 overhead in [uncompressed] kernel size for
   CRCs.

Switching to explicit 32 bit values on 64 bit architectures fixes most
of these issues, given that 32 bit values are not treated as quantities
that require fixing up based on the actual runtime load offset.  Note
that on some ELF64 architectures [such as PPC64], these 32-bit values
are still emitted as [absolute] runtime relocatable quantities, even if
the value resolves to a build time constant.  Since relative relocations
are always resolved at build time, this patch enables MODULE_REL_CRCS on
powerpc when CONFIG_RELOCATABLE=y, which turns the absolute CRC
references into relative references into .rodata where the actual CRC
value is stored.

So redefine all CRC fields and variables as u32, and redefine the
__CRC_SYMBOL() macro for 64 bit builds to emit the CRC reference using
inline assembler (which is necessary since 64-bit C code cannot use
32-bit types to hold memory addresses, even if they are ultimately
resolved using values that do not exceed 0xffffffff).  To avoid
potential problems with legacy 32-bit architectures using legacy
toolchains, the equivalent C definition of the kcrctab entry is retained
for 32-bit architectures.

Note that this mostly reverts commit d4703aef ("module: handle ppc64
relocating kcrctabs when CONFIG_RELOCATABLE=y")
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Enable support for GCC plugins on powerpc.

Add an additional version check in gcc-plugins-check to advise users to
upgrade to gcc 5.2+ on powerpc to avoid issues with header files (gcc <=
4.6) or missing copies of rs6000-cpus.def (4.8 to 5.1 on 64-bit
targets).
Signed-off-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We added support for HAVE_CONTEXT_TRACKING, but placed the option inside
PPC_PSERIES.

This has the undesirable effect that NO_HZ_FULL can be enabled on a
kernel with both powernv and pseries support, but cannot on a kernel
with powernv only support.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch implements HW breakpoint on the 8xx. The 8xx has
capability to manage HW breakpoints, which is slightly different
than BOOK3S:
1/ The breakpoint match doesn't trigger a DSI exception but a
dedicated data breakpoint exception.
2/ The breakpoint happens after the instruction has completed,
no need to single step or emulate the instruction,
3/ Matched address is not set in DAR but in BAR,
4/ DABR register doesn't exist, instead we have registers
LCTRL1, LCTRL2 and CMPx registers,
5/ The match on one comparator is not on a double word but
on a single word.

The patch does:
1/ Prepare the dedicated registers in call to __set_dabr(). In order
to emulate the double word handling of BOOK3S, comparator E is set to
DABR address value and comparator F to address + 4. Then breakpoint 1
is set to match comparator E or F,
2/ Skip the singlestepping stage when compiled for CONFIG_PPC_8xx,
3/ Implement the exception. In that exception, the matched address
is taken from SPRN_BAR and manage as if it was from SPRN_DAR.
4/ I/D TLB error exception routines perform a tlbie on bad TLBs. That
tlbie triggers the breakpoint exception when performed on the
breakpoint address. For this reason, the routine returns if the match
is from one of those two tlbie.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

BOOK3S also has DABR register and capability to handle data
breakpoints, so this patch enable it on all BOOK3S, not only 64 bits.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

Currently we have optimized hand-coded assembly checksum routines for
big-endian 64-bit systems, but for little-endian we use the generic C
routines. This modifies the optimized routines to work for
little-endian. With this, we no longer need to enable
CONFIG_GENERIC_CSUM. This also fixes a couple of comments in
checksum_64.S so they accurately reflect what the associated instruction
does.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
[mpe: Use the more common __BIG_ENDIAN__]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Unfortunately the stack protector support we merged recently only works
on some toolchains. If the toolchain is built without glibc support
everything works fine, but if glibc is built then it leads to a panic
at boot.

The solution is not rc5 material, so revert the support for now. This
reverts commits:

6533b7c1 ("powerpc: Initial stack protector (-fstack-protector) support")
902e06eb ("powerpc/32: Change the stack protector canary value per task")

Fixes: 6533b7c1 ("powerpc: Initial stack protector (-fstack-protector) support")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Patch series "ima: carry the measurement list across kexec", v8.

The TPM PCRs are only reset on a hard reboot.  In order to validate a
TPM's quote after a soft reboot (eg.  kexec -e), the IMA measurement
list of the running kernel must be saved and then restored on the
subsequent boot, possibly of a different architecture.

The existing securityfs binary_runtime_measurements file conveniently
provides a serialized format of the IMA measurement list.  This patch
set serializes the measurement list in this format and restores it.

Up to now, the binary_runtime_measurements was defined as architecture
native format.  The assumption being that userspace could and would
handle any architecture conversions.  With the ability of carrying the
measurement list across kexec, possibly from one architecture to a
different one, the per boot architecture information is lost and with it
the ability of recalculating the template digest hash.  To resolve this
problem, without breaking the existing ABI, this patch set introduces
the boot command line option "ima_canonical_fmt", which is arbitrarily
defined as little endian.

The need for this boot command line option will be limited to the
existing version 1 format of the binary_runtime_measurements.
Subsequent formats will be defined as canonical format (eg.  TPM 2.0
support for larger digests).

A simplified method of Thiago Bauermann's "kexec buffer handover" patch
series for carrying the IMA measurement list across kexec is included in
this patch set.  The simplified method requires all file measurements be
taken prior to executing the kexec load, as subsequent measurements will
not be carried across the kexec and restored.

This patch (of 10):

The IMA kexec buffer allows the currently running kernel to pass the
measurement list via a kexec segment to the kernel that will be kexec'd.
The second kernel can check whether the previous kernel sent the buffer
and retrieve it.

This is the architecture-specific part which enables IMA to receive the
measurement list passed by the previous kernel.  It will be used in the
next patch.

The change in machine_kexec_64.c is to factor out the logic of removing
an FDT memory reservation so that it can be used by remove_ima_buffer.

Link: http://lkml.kernel.org/r/1480554346-29071-2-git-send-email-zohar@linux.vnet.ibm.comSigned-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andreas Steffen <andreas.steffen@strongswan.org>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Josh Sklar <sklar@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is used in poison.h to offset poison values so that they don't
point directly into user space.

The value we choose sits roughly between user and kernel space, which
means on their own the poison values don't point anywhere useful. If an
attacker can cause an access at some offset from the poison value then
we may still be in trouble, but by putting the poison values between
user and kernel space we maximise the required size of that offset.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Define the Kconfig symbol so that the kexec_file_load() code can be
built, and wire up the syscall so that it can be called.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 2965faa5 ("kexec: split kexec_load syscall from kexec core
code") introduced CONFIG_KEXEC_CORE so that CONFIG_KEXEC means whether
the kexec_load system call should be compiled-in and CONFIG_KEXEC_FILE
means whether the kexec_file_load system call should be compiled-in.
These options can be set independently from each other.

Since until now powerpc only supported kexec_load, CONFIG_KEXEC and
CONFIG_KEXEC_CORE were synonyms. That is not the case anymore, so we
need to make a distinction. Almost all places where CONFIG_KEXEC was
being used should be using CONFIG_KEXEC_CORE instead, since
kexec_file_load also needs that code compiled in.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Partialy copied from commit c743f380 ("ARM: initial stack protector
(-fstack-protector) support")

This is the very basic stuff without the changing canary upon
task switch yet.  Just the Kconfig option and a constant canary
value initialized at boot time.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Add an option to use thin archives to build the kernel.
Thin archives are explained in commit a5967db9 ("kbuild: allow
architectures to use thin archives instead of ld -r").

This is a gradual way to introduce the option to testers.

Some change to the way we invoke ar is required so it can be used
by scripts/link-vmlinux.sh.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
[mpe: Make it an explicit option not dependant on COMPILE_TEST]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Only s390 and powerpc have hardware facilities allowing to measure
cputimes scaled by frequency. On all other architectures
utimescaled/stimescaled are equal to utime/stime (however they are
accounted separately).

Remove {u,s}timescaled accounting on all architectures except
powerpc and s390, where those values are explicitly accounted
in the proper places.
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161031162143.GB12646@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This adds a config option that can help exercise the case when
the kernel is not running at PAGE_OFFSET.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Reviewed-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This came to light when implementing native 64-bit atomics for ARCv2.

The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
to check whether atomic64_dec_if_positive() is available.  It seems it
was needed when not every arch defined it.  However as of current code
the Kconfig option seems needless

 - for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
   generic definition of API is present lib/atomic64.c
 - arches with native 64-bit atomics select it in arch/*/Kconfig and
   define the API in their headers

So I see no point in keeping the Kconfig option

Compile tested for:
 - blackfin (CONFIG_GENERIC_ATOMIC64)
 - x86 (!CONFIG_GENERIC_ATOMIC64)
 - ia64

Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.comSigned-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ming Lin <ming.l@ssi.samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

POWER8 handles unaligned accesses in little endian mode, but commit
0b5e6661 ("powerpc: Don't set HAVE_EFFICIENT_UNALIGNED_ACCESS on
little endian builds") disabled it for all.

The issue with unaligned little endian accesses is specific to POWER7,
so update the Kconfig check to match. Using the stat() testcase from
commit a75c380c ("powerpc: Enable DCACHE_WORD_ACCESS on ppc64le"),
performance improves 15% on POWER8.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Most architectures allow the compression algorithm used to produced the
vmlinuz image to be selected as a kernel config option. In preperation
for supporting algorithms other than gzip in the powerpc boot wrapper
the makefile needs to be modified to use these config options.
Signed-off-by: NOliver O'Halloran <oohall@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

For hugetlb to work with 4K page size, we need MAX_ORDER to be 13 or
more. When switching from a 64K page size to 4K linux page size using
make oldconfig, we end up with a CONFIG_FORCE_MAX_ZONEORDER value of 9.
This results in a 16M hugepage beiing considered as a gigantic huge page
which in turn results in failure to setup hugepages if gigantic hugepage
support is not enabled.

This also results in kernel crash with 4K radix configuration. We
hit the below BUG_ON on radix:

  kernel BUG at mm/huge_memory.c:364!
  Oops: Exception in kernel mode, sig: 5 [#1]
  SMP NR_CPUS=2048 NUMA PowerNV
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.8.0-rc1-00006-gbae9cc6 #1
  task: c0000000f1af8000 task.stack: c0000000f1aec000
  NIP: c000000000c5fa0c LR: c000000000c5f9d8 CTR: c000000000c5f9a4
  REGS: c0000000f1aef920 TRAP: 0700   Not tainted (4.8.0-rc1-00006-gbae9cc6)
  MSR: 9000000102029033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]>  CR: 24000844  XER: 00000000
  CFAR: c000000000c5f9e0 SOFTE: 1
  ....
  NIP [c000000000c5fa0c] hugepage_init+0x68/0x238
  LR [c000000000c5f9d8] hugepage_init+0x34/0x238

Fixes: a7ee5395 ("powerpc/Kconfig: Update config option based on page size")
Cc: stable@vger.kernel.org # v4.7+
Reported-by: NSanthosh <santhog4@linux.vnet.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 2578bfae ("[POWERPC] Create and use CONFIG_WORD_SIZE") added
CONFIG_WORD_SIZE, and suggests that other arches were going to do
likewise.

But that never happened, powerpc is the only architecture which uses it.

So switch to using a simple make variable, BITS, like x86, sh, sparc and
tile. It is also easier to spell and simpler, avoiding any confusion
about whether it's defined due to ordering of make vs kconfig.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>