2376 Commits

Author SHA1 Message Date
Álvaro Fernández Rojas
3604b4510c MIPS: BMIPS: Add BCM6358 support
BCM6358 has a shared TLB which conflicts with current SMP support, so it must
be disabled for now.
BCM6358 uses >= 0xfffe0000 addresses for internal registers, which need to be
remapped (by using a simplified version of BRCM63xx ioremap.h).
However, 0xfff80000 is a better address, since it also covers BCM3368, leaving
the possibility to add it in the future.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Cc: f.fainelli@gmail.com
Cc: jogo@openwrt.org
Cc: cernekee@gmail.com
Cc: robh@kernel.org
Cc: simon@fire.lp0.eu
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13040/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:09 +02:00
Florian Fainelli
f337967d6d MIPS: BMIPS: Add cpu-feature-overrides.h
BMIPS_GENERIC being multiplatform and intended to support BMIPS3200,
BMIPS3300, BMIPS4350, BMIPS4380 and BMIPS5000-class processors, there is
not much more we can put in there since they do not share the same I and
D cache line sizes at all (doubled for every new generation
essentially), some processors have a S-cache, some don't, some have a
FPU, some don't.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13013/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:07 +02:00
Kelvin Cheung
9ec88b60cb MIPS: Loongson1B: Some updates/fixes for LS1B
- Add DMA device
- Add NAND device
- Add GPIO device
- Add LED device
- Update the defconfig and rename it to loongson1b_defconfig
- Fix ioremap size
- Other minor fixes

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: dmaengine@vger.kernel.org
Cc: linux-gpio@vger.kernel.org
Cc: linux-mtd@lists.infradead.org
Patchwork: https://patchwork.linux-mips.org/patch/13033/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:05 +02:00
Matt Redfearn
5e7c1c918a MIPS: Introduce plat_get_fdt a platform API to retrieve the FDT
Early access to the kernel command line requires early access to the FDT
for platforms which pass the command line within the device tree. There
was no common way to retrieve the location of the FDT without incurring
side effects, such as plat_mem_setup which, on Malta at least,
initializes a bunch of other stuff.

This patch adds plat_get_ftd() for IMG platforms.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12988/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:03 +02:00
Matt Redfearn
b1b4fad5cc MIPS: seccomp: Support compat with both O32 and N32
Previously the seccomp would only support strict mode on O32 userland
programs when the kernel had support for both O32 and N32 ABIs. Remove
kludge and support both ABIs.

With this patch in place, the seccomp_bpf self test now passes
global.mode_strict_support with N32 userland.

Suggested-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: IMG-MIPSLinuxKerneldevelopers@imgtec.com
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12917/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:01 +02:00
Stephen Boyd
3d2ca73af4 MIPS: Use generic clkdev.h header
The generic header file is equivalent to the MIPS one, so use the
generic one instead.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12261/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:58 +02:00
Paul Burton
37d22a0d79 MIPS: Sync icache & dcache in set_pte_at
It's possible for pages to become visible prior to update_mmu_cache
running if a thread within the same address space preempts the current
thread or runs simultaneously on another CPU. That is, the following
scenario is possible:

    CPU0                            CPU1

    write to page
    flush_dcache_page
    flush_icache_page
    set_pte_at
                                    map page
    update_mmu_cache

If CPU1 maps the page in between CPU0's set_pte_at, which marks it valid
& visible, and update_mmu_cache where the dcache flush occurs then CPU1s
icache will fill from stale data (unless it fills from the dcache, in
which case all is good, but most MIPS CPUs don't have this property).
Commit 4d46a67a3eb8 ("MIPS: Fix race condition in lazy cache flushing.")
attempted to fix that by performing the dcache flush in
flush_icache_page such that it occurs before the set_pte_at call makes
the page visible. However it has the problem that not all code that
writes to pages exposed to userland call flush_icache_page. There are
many callers of set_pte_at under mm/ and only 2 of them do call
flush_icache_page. Thus the race window between a page becoming visible
& being coherent between the icache & dcache remains open in some cases.

To illustrate some of the cases, a WARN was added to __update_cache with
this patch applied that triggered in cases where a page about to be
flushed from the dcache was not the last page provided to
flush_icache_page. That is, backtraces were obtained for cases in which
the race window is left open without this patch. The 2 standout examples
follow.

When forking a process:

[   15.271842] [<80417630>] __update_cache+0xcc/0x188
[   15.277274] [<80530394>] copy_page_range+0x56c/0x6ac
[   15.282861] [<8042936c>] copy_process.part.54+0xd40/0x17ac
[   15.289028] [<80429f80>] do_fork+0xe4/0x420
[   15.293747] [<80413808>] handle_sys+0x128/0x14c

When exec'ing an ELF binary:

[   14.445964] [<80417630>] __update_cache+0xcc/0x188
[   14.451369] [<80538d88>] move_page_tables+0x414/0x498
[   14.457075] [<8055d848>] setup_arg_pages+0x220/0x318
[   14.462685] [<805b0f38>] load_elf_binary+0x530/0x12a0
[   14.468374] [<8055ec3c>] search_binary_handler+0xbc/0x214
[   14.474444] [<8055f6c0>] do_execveat_common+0x43c/0x67c
[   14.480324] [<8055f938>] do_execve+0x38/0x44
[   14.485137] [<80413808>] handle_sys+0x128/0x14c

These code paths write into a page, call flush_dcache_page then call
set_pte_at without flush_icache_page inbetween. The end result is that
the icache can become corrupted & userland processes may execute
unexpected or invalid code, typically resulting in a reserved
instruction exception, a trap or a segfault.

Fix this race condition fully by performing any cache maintenance
required to keep the icache & dcache in sync in set_pte_at, before the
page is made valid. This has the added bonus of ensuring the cache
maintenance always happens in one location, rather than being duplicated
in flush_icache_page & update_mmu_cache. It also matches the way other
architectures solve the same problem (see arm, ia64 & powerpc).

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reported-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Cc: Lars Persson <lars.persson@axis.com>
Fixes: 4d46a67a3eb8 ("MIPS: Fix race condition in lazy cache flushing.")
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable <stable@vger.kernel.org> # v4.1+
Patchwork: https://patchwork.linux-mips.org/patch/12722/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:58 +02:00
Paul Burton
763fee97e7 MIPS: Flush dcache for flush_kernel_dcache_page
The flush_kernel_dcache_page function was previously essentially a nop.
This is incorrect for MIPS, where if a page has been modified & either
it aliases or it's executable & the icache doesn't fill from dcache then
the content needs to be written back from dcache to the next level of
the cache hierarchy (which is shared with the icache).

Implement this by simply calling flush_dcache_page, treating this
kmapped cache flush function (flush_kernel_dcache_page) exactly the same
as its non-kmapped counterpart (flush_dcache_page).

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Lars Persson <lars.persson@axis.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12719/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:57 +02:00
Zubair Lutfullah Kakakhel
b5a6455cde MIPS: Detect DSP v3 support
DSPv3 is supported on all MIPSr6 systems which indicate support for DSPv2.

This doesn't require any changes to the kernel's handling of DSP
resources. The patch is to detect support and indicate it in /proc/cpuinfo

DSP v3 introduces a new instruction BPOSGE32C

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12918/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:57 +02:00
James Hogan
0c94fa33b4 MIPS: cpu: Convert MIPS_CPU_* defs to (1ull << x)
The MIPS_CPU_* definitions have now filled the first 32-bits, and are
getting longer since they're written in hex without zero padding. Adding
my 8 extra MIPS_CPU_* definitions which I haven't upstreamed yet this is
getting increasingly ugly as the comments get shifted progressively to
the right. Its also error prone, and I've seen this cause mistakes on 3
separate occasions now, not helped by it being a conflict hotspot.

Convert all the MIPS_CPU_* definitions to the form (1ull << x). Humans
are better at incrementing than shifting.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10045/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:56 +02:00
James Hogan
c0291f7c73 MIPS: cpu: Alter MIPS_CPU_* definitions to fill gap
The MIPS_CPU_* definitions accidentally missed bits 27..30 when
MIPS_CPU_EVA was added, and further definitions have continued from
there.

Shift all the definitions since MIPS_CPU_EVA right by 4 so there are no
gaps.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10044/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:55 +02:00
Florian Fainelli
738a3f7902 MIPS: BMIPS: Add early CPU initialization code
Port the stblinux-3.3 code to perform a bunch of CPU-specific initialization,
make it compatible with run-time detection of the CPU, and unroll the
brcmstb-specific macros: BDEV_RB(), BDEV_UNSET.

The "pref 30" disabling is done as a quirk. This is a preliminary change to
allow the use of the "rotr" instruction gated by cpu_has_rixi.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jon.fraser@broadcom.com
Cc: pgynther@google.com
Cc: paul.burton@imgtec.com
Cc: ddaney.cavm@gmail.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12504/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:55 +02:00
Ralf Baechle
04cc89d120 MIPS: Make flush_thread
Avoids function calls to an empty function.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:54 +02:00
Paul Burton
ad8319ea46 MIPS: Support R_MIPS_PC{21,26} rela-style relocs
MIPS64 code uses rela-style relocs, and MIPS64r6 modules may include the
new R_MIPS_PC21 & R_MIPS_PC26 relocations. We thus need to support these
relocations in order to load MIPS64r6 kernel modules. They are similar
to the existing R_MIPS_PC16 relocation but applying to a wider field.
Implement support for them by genericising the existing R_MIPS_PC16
implementation such that it can be used for different field widths, and
calling it for all 3 reloc types.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12434/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:54 +02:00
Paul Burton
1dbf6a81c8 MIPS: Add M6250 cases to CPU switch statements
Add casses supporting the M6250 CPU to various switch statements in the
core MIPS kernel code that define behaviour dependent upon the CPU.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12374/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:53 +02:00
Paul Burton
df8b1a5ee9 MIPS: Add M6250 PRID & cpu_type_enum values
Define the processor ID for the M6250 CPU and add a value to the enum
cpu_type_enum for the core.

[ralf@linux-mips.org: Fix merge conflict.]

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12373/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:53 +02:00
Paul Burton
1091bfa20b MIPS: Add P6600 cases to CPU switch statements
Add cases supporting the P6600 CPU to various switch statements in
core MIPS kernel code that define behaviour dependent upon the CPU.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petri Gynther <pgynther@google.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12343/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:52 +02:00
Paul Burton
5cd0d5beef MIPS: Add P6600 PRID & cpu_type_enum values
Define the processor ID for the P6600 core and add a value to the enum
cpu_type_enum for the core.

[ralf@linux-mips.org: Fix merge conflict.]

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12342/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:52 +02:00
Ralf Baechle
bff3d472b8 MIPS: <asm/cpu.h>: Reformat to 80 columns.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:51 +02:00
Paul Burton
5a3e7c02d8 MIPS: smp-cps: Support MIPSr6 Virtual Processors
Introduce support for bringing up Virtual Processors in MIPSr6 systems
as CPUs, much like their VPE parallel from the now-deprecated MT ASE.
The existing mips_cps_boot_vpes function fits the MIPSr6 architecture
pretty well - it can now simply write the mask of running VPs to the
VC_RUN register, rather than looping through each & starting or stopping
as appropriate as is done for VPEs from the MT ASE. Thus the VP support
is in general an extension & simplification of the existing MT ASE VPE
(aka SMVP) support.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12339/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton
f12401d721 MIPS: smp-cps: Pull boot config retrieval out of mips_cps_boot_vpes
The mips_cps_boot_vpes function previously included code to retrieve
pointers to the core & VPE boot configuration structs. These structures
were used both by mips_cps_boot_vpes and by its mips_cps_core_entry
callsite. In preparation for skipping the call to mips_cps_boot_vpes on
some invocations of mips_cps_core_entry, pull the calculation of those
pointers out into a separate function such that it can continue to be
shared.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12337/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton
a60ae81e5e MIPS: CM: Fix mips_cm_max_vp_width for UP kernels
Fix mips_cm_max_vp_width for UP kernels where it previously referenced
smp_num_siblings, which is not declared for UP kernels. This led to
build errors such as the following:

  drivers/built-in.o: In function `$L446':
  irq-mips-gic.c:(.text+0x1994): undefined reference to `smp_num_siblings'
  drivers/built-in.o:irq-mips-gic.c:(.text+0x199c): more undefined references to `smp_num_siblings' follow

On UP kernels simply return 1, leaving the reference to smp_num_siblings
in place only for SMP kernels.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12332/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:48 +02:00
Paul Burton
db8e00af7b MIPS: CM: Add CM GCR_BEV_BASE accessors
Generate accessor functions for the GCR_BEV_BASE register introduced by
CM3, for use by a later patch.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12331/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:48 +02:00
Markos Chandras
88036557ba MIPS: CPC: Add start, stop and running CM3 CPC registers
Add the new CM3 registers for controlling bringing up and powering down
VPs on MIPSR6 cores.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12330/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:48 +02:00
Paul Burton
f270d881fa MIPS: Detect MIPSr6 Virtual Processor support
MIPSr6 introduces support for "Virtual Processors", which are
conceptually similar to VPEs from the now-deprecated MT ASE. Detect
whether the system supports VPs using the VP bit in Config5, adding
cpu_has_vp for use by later patches.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12327/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:47 +02:00
Aaro Koskinen
6ecffafe24 MIPS: Octeon: board_type_to_string: return NULL for unsupported board
Return NULL for unsupported board.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12581/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:41 +02:00
David Daney
c6d2b22eb5 MIPS: OCTEON: Add SMP support for OCTEON cn78xx et al.
OCTEON chips with the CIU3 interrupt controller use a different IPI
mechanism that previous models.

Add plat_smp_ops for the cn78xx and probing code to choose between the
two types of ops.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12499/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:41 +02:00
David Daney
ce210d35bb MIPS: OCTEON: Add support for OCTEON III interrupt controller.
Add irq_chip support for both IPI and "normal" interrupts of the CIU3
controller.  Document the device tree binding for the CIU3.

Some functions are non-static as they will be used by follow-on
support for MSI-X.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: devicetree@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12500/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:41 +02:00
David Daney
182a6d1cd3 MIPS: OCTEON: Add model checking support for cn73xx, cnf75xx and cn78xx
Follow on patchs need to be able to distinguish the new models.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12498/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:40 +02:00
David Daney
2df11221bd MIPS: OCTEON: Add register definitions for cn73xx, cnf75xx and cn78xx.
These new members of the OCTEON III family have some new registers,
update some of the definitions for use in follow on patches.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12497/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:40 +02:00
David Daney
1d2753a66a MIPS: Select CONFIG_HANDLE_DOMAIN_IRQ and make it work.
Per the subject, always select HANDLE_DOMAIN_IRQ, and implement
set_irq_regs() so that it actually works.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12496/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:40 +02:00
David Daney
7d52ab163c MIPS: OCTEON: Extend number of supported CPUs past 32
To support more than 48 CPUs, the bootinfo structure grows a new
coremask structure.  Add the definition of the structure and add it to
struct cvmx_bootinfo.  In prom_init(), copy the new coremask data into
the sysinfo structure, and use it in smp_setup().

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12319/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:39 +02:00
David Daney
58546e3b73 MIPS: OCTEON: Remove dead code from cvmx-sysinfo.
Get rid of the long unused code.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12318/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:39 +02:00
David Daney
b8c8f66507 MIPS: Add CPU identifiers and probing for Cavium CN73xx and CNF75xx processors.
Add new processor identifiers for Cavium CN73xx and CNF75xx
processors, and probe for them in cpu-probe.c

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12311/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:38 +02:00
Ralf Baechle
34ae8e3688 MIPS: highmem: Turn flush_cache_kmaps into a no-op.
It was calling flush_cache_all() which is a no-op since a long time anyway
and which was overkill in the old days when it was actually doing something
because only the D-cache needs to be flushed, never the I-cache, never
the S-cache.  Since however highmem on MIPS is still only supported on
processors that don't suffer from cache aliases, we could turn
flush_cache_kmaps() into a no-op - but for paranoia's sake we rather make
it BUG_ON(cpu_has_dc_aliases()).

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:38 +02:00
Joshua Kinard
128639395b MIPS: Adjust set_pte() SMP fix to handle R10000_LLSC_WAR
Update the recent changes to set_pte() that were added in 46011e6ea392
to handle R10000_LLSC_WAR, and format the assembly to match other areas
of the MIPS tree using the same WAR.

This also incorporates a patch recently sent in my Markos Chandras,
"Remove local LL/SC preprocessor variants", so that patch doesn't need
to be applied if this one is accepted.

Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Fixes: 46011e6ea392 ("MIPS: Make set_pte() SMP safe.)
Cc: David Daney <david.daney@cavium.com>
Cc: Linux/MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/11103/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:05 +02:00
Ralf Baechle
05490626d5 MIPS: Move definitions for 32/64-bit agonstic inline assembler to new file.
Inspired by Markos Chandras' patch.  I just didn't want do pull bitsops.h
into pgtable.h.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
References: https://patchwork.linux-mips.org/patch/11052/
2016-05-09 12:00:05 +02:00
James Hogan
92e9953c58 MIPS: Fix MSA assembly warnings
Building an MSA capable kernel with a toolchain that supports MSA
produces warnings such as this:

arch/mips/kernel/r4k_fpu.S:229: Warning: the `msa' extension requires 64-bit FPRs

This is due to ".set msa" without ".set fp=64" in the non doubleword MSA
load/store macros, since MSA requires the 64-bit FPU registers (FR=1).
Add the missing fp=64 in these macros to silence the warnings.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13063/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:05 +02:00
James Hogan
143e93d74e MIPS: Fix MSA assembly with big thread offsets
When lockdep is enabled on a 64-bit kernel the FPR offset into the
thread structure exceeds the maximum range of the MSA ld.d/st.d
instructions. For example THREAD_FPR31 = 4644 (instead of 2448), while
the signed immediate field is only 10 bits with an implicit multiply by
8, giving a maximum offset of 511*8 = 4088.

This isn't a problem when the toolchain doesn't support MSA as the
ld_*/st_* macros perform the addition separately into $1 with [d]addui
which has a 16bit signed immediate field.

Fix the case where the toolchain does support MSA by doing a single
addition of THREAD_FPR0 into $1 with [d]addui, and doing the ld_*/st_*
relative to that.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13064/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:05 +02:00
James Hogan
ea16885734 MIPS: Fix MSA ld_*/st_* asm macros to use PTR_ADDU
The MSA ld_*/st_* assembler macros for when the toolchain doesn't
support MSA use addu to offset the base address. However it is a virtual
memory pointer so fix it to use PTR_ADDU which expands to daddu for
64-bit kernels.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.3.y-
Patchwork: https://patchwork.linux-mips.org/patch/13062/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:04 +02:00
Paul Burton
8a3c8b48ac MIPS: Use copy_s.fmt rather than copy_u.fmt
In revision 1.12 of the MSA specification, the copy_u.w instruction has
been removed for MIPS32 & the copy_u.d instruction has been removed for
MIPS64. Newer toolchains (eg. Codescape SDK essentials 2015.10) will
complain about this like so:

arch/mips/kernel/r4k_fpu.S:290: Error: opcode not supported on this
processor: mips32r2 (mips32r2) `copy_u.w $1,$w26[3]'

Since we always copy to the width of a GPR, simply use copy_s instead of
copy_u to fix this.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.3.x+
Patchwork: https://patchwork.linux-mips.org/patch/13061/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:04 +02:00
James Hogan
a7e89326b4 MIPS: Fix watchpoint restoration
Commit f51246efee2b ("MIPS: Get rid of finish_arch_switch().") moved the
__restore_watch() call from finish_arch_switch() (i.e. after resume()
returns) to before the resume() call in switch_to(). This results in
watchpoints only being restored when a task is descheduled, preventing
the watchpoints from being effective most of the time, except due to
chance before the watchpoints are lazily removed.

Fix the call sequence from switch_to() through to
mips_install_watch_registers() to pass the task_struct pointer of the
next task, instead of using current. This allows the watchpoints for the
next (non-current) task to be restored without reintroducing
finish_arch_switch().

Fixes: f51246efee2b ("MIPS: Get rid of finish_arch_switch().")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.3.x-
Patchwork: https://patchwork.linux-mips.org/patch/12726/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:02 +02:00
James Hogan
5daebc477d MIPS: Fix siginfo.h to use strict posix types
Commit 85efde6f4e0d ("make exported headers use strict posix types")
changed the asm-generic siginfo.h to use the __kernel_* types, and
commit 3a471cbc081b ("remove __KERNEL_STRICT_NAMES") make the internal
types accessible only to the kernel, but the MIPS implementation hasn't
been updated to match.

Switch to proper types now so that the exported asm/siginfo.h won't
produce quite so many compiler errors when included alone by a user
program.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Christopher Ferris <cferris@google.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 2.6.30-
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12477/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:00 +02:00
Nikolay Martynov
e03ac9f0c3 mips: Fix CPC_BASE_ADDR mask to match datasheet
According to 'MIPS32® interAptivTM Multiprocessing
System Programmer’s Guide' CPC_BASE_ADDR takes bits [31:15].

This change is tested ith mt7621 which wasn't working without it.

Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11766/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:00 +02:00
Maciej W. Rozycki
3b143cca6e MIPS: traps: Correct the SIGTRAP debug ABI in do_watch' and do_trap_or_bp'
Follow our own rules set in <asm/siginfo.h> for SIGTRAP signals issued
from `do_watch' and `do_trap_or_bp' by setting the signal code to
TRAP_HWBKPT and TRAP_BRKPT respectively, for Watch exceptions and for
those Breakpoint exceptions whose originating BREAK instruction's code
does not have a special meaning.  Keep Trap exceptions unaffected as
these are not debug events.

No existing user software is expected to examine signal codes for these
signals as SI_KERNEL has been always used here.  This change makes the
MIPS port more like other Linux ports, which reduces the complexity and
provides for performance improvement in GDB.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Luis Machado <lgustavo@codesourcery.com>
Cc: linux-mips@linux-mips.org
Cc: gdb@sourceware.org
Patchwork: https://patchwork.linux-mips.org/patch/12758/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 12:32:09 +02:00
Adam Buchbinder
92a76f6d85 MIPS: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12617/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 12:32:09 +02:00
Ralf Baechle
62d8e64423 MIPS: Wire up preadv2 and pwrite2 syscalls.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 09:41:34 +02:00
James Hogan
e95008a121 MIPS: cpu_name_string: Use raw_smp_processor_id().
If cpu_name_string() is used in non-atomic context when preemption is
enabled, it can trigger a BUG such as this one:

BUG: using smp_processor_id() in preemptible [00000000] code: unaligned/156
caller is __show_regs+0x1e4/0x330
CPU: 2 PID: 156 Comm: unaligned Tainted: G        W       4.3.0-00366-ga3592179816d-dirty #1501
Stack : ffffffff80900000 ffffffff8019bc18 000000000000005f ffffffff80a20000
         0000000000000000 0000000000000009 ffffffff8019c0e0 ffffffff80835648
         a8000000ff2bdec0 ffffffff80a1e628 000000000000009c 0000000000000002
         ffffffff80840000 a8000000fff2ffb0 0000000000000020 ffffffff8020e43c
         a8000000fff2fcf8 ffffffff80a20000 0000000000000000 ffffffff808f2607
         ffffffff8082b138 ffffffff8019cd1c 0000000000000030 ffffffff8082b138
         0000000000000002 000000000000009c 0000000000000000 0000000000000000
         0000000000000000 a8000000fff2fc40 0000000000000000 ffffffff8044dbf4
         0000000000000000 0000000000000000 0000000000000000 ffffffff8010c400
         ffffffff80855bb0 ffffffff8010d008 0000000000000000 ffffffff8044dbf4
         ...
Call Trace:
[<ffffffff8010d008>] show_stack+0x90/0xb0
[<ffffffff8044dbf4>] dump_stack+0x84/0xe0
[<ffffffff8046d4ec>] check_preemption_disabled+0x10c/0x110
[<ffffffff8010c40c>] __show_regs+0x1e4/0x330
[<ffffffff8010d060>] show_registers+0x28/0xc0
[<ffffffff80110748>] do_ade+0xcc8/0xce0
[<ffffffff80105b84>] resume_userspace_check+0x0/0x10

This is possible because cpu_name_string() is used by __show_regs(),
which is used by both show_regs() and show_registers(). These two
functions are used by various exception handling functions, only some of
which ensure that interrupts or preemption is disabled.

However the following have interrupts explicitly enabled or not
explicitly disabled:
- do_reserved() (irqs enabled)
- do_ade() (irqs not disabled)

This can be hit by setting /sys/kernel/debug/mips/unaligned_action to 2,
and triggering an address error exception, e.g. an unaligned access or
access to kernel segment from user mode.

To fix the above cases, use raw_smp_processor_id() instead. It is
unusual for CPU names to be different in the same system, and even if
they were, its possible the process has migrated between the exception
of interest and the cpu_name_string() call anyway.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12212/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-03-29 23:56:36 +02:00
Linus Torvalds
8f40842e42 MTD updates for v4.6
NAND:
  * Add sunxi_nand randomizer support
  * begin refactoring NAND ecclayout structs
  * fix pxa3xx_nand dmaengine usage
  * brcmnand: fix support for v7.1 controller
  * add Qualcomm NAND controller driver
 
 SPI NOR:
  * add new ls1021a, ls2080a support to Freescale QuadSPI
  * add new flash ID entries
  * support bottom-block protection for Winbond flash
  * support Status Register Write Protect
  * remove broken QPI support for Micron SPI flash
 
 JFFS2:
  * improve post-mount CRC scan efficiency
 
 General:
  * refactor bcm63xxpart parser, to later extend for NAND
  * add writebuf size parameter to mtdram
 
 Other minor code quality improvements
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Merge tag 'for-linus-20160324' of git://git.infradead.org/linux-mtd

Pull MTD updates from Brian Norris:
 "NAND:
   - Add sunxi_nand randomizer support
   - begin refactoring NAND ecclayout structs
   - fix pxa3xx_nand dmaengine usage
   - brcmnand: fix support for v7.1 controller
   - add Qualcomm NAND controller driver

  SPI NOR:
   - add new ls1021a, ls2080a support to Freescale QuadSPI
   - add new flash ID entries
   - support bottom-block protection for Winbond flash
   - support Status Register Write Protect
   - remove broken QPI support for Micron SPI flash

  JFFS2:
   - improve post-mount CRC scan efficiency

  General:
   - refactor bcm63xxpart parser, to later extend for NAND
   - add writebuf size parameter to mtdram

  Other minor code quality improvements"

* tag 'for-linus-20160324' of git://git.infradead.org/linux-mtd: (72 commits)
  mtd: nand: remove kerneldoc for removed function parameter
  mtd: nand: Qualcomm NAND controller driver
  dt/bindings: qcom_nandc: Add DT bindings
  mtd: nand: don't select chip in nand_chip's block_bad op
  mtd: spi-nor: support lock/unlock for a few Winbond chips
  mtd: spi-nor: add TB (Top/Bottom) protect support
  mtd: spi-nor: add SPI_NOR_HAS_LOCK flag
  mtd: spi-nor: use BIT() for flash_info flags
  mtd: spi-nor: disallow further writes to SR if WP# is low
  mtd: spi-nor: make lock/unlock bounds checks more obvious and robust
  mtd: spi-nor: silently drop lock/unlock for already locked/unlocked region
  mtd: spi-nor: wait for SR_WIP to clear on initial unlock
  mtd: nand: simplify nand_bch_init() usage
  mtd: mtdswap: remove useless if (!mtd->ecclayout) test
  mtd: create an mtd_oobavail() helper and make use of it
  mtd: kill the ecclayout->oobavail field
  mtd: nand: check status before reporting timeout
  mtd: bcm63xxpart: give width specifier an 'int', not 'size_t'
  mtd: mtdram: Add parameter for setting writebuf size
  mtd: nand: pxa3xx_nand: kill unused field 'drcmr_cmd'
  ...
2016-03-24 19:57:15 -07:00
Linus Torvalds
643ad15d47 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
 "This tree adds support for a new memory protection hardware feature
  that is available in upcoming Intel CPUs: 'protection keys' (pkeys).

  There's a background article at LWN.net:

      https://lwn.net/Articles/643797/

  The gist is that protection keys allow the encoding of
  user-controllable permission masks in the pte.  So instead of having a
  fixed protection mask in the pte (which needs a system call to change
  and works on a per page basis), the user can map a (handful of)
  protection mask variants and can change the masks runtime relatively
  cheaply, without having to change every single page in the affected
  virtual memory range.

  This allows the dynamic switching of the protection bits of large
  amounts of virtual memory, via user-space instructions.  It also
  allows more precise control of MMU permission bits: for example the
  executable bit is separate from the read bit (see more about that
  below).

  This tree adds the MM infrastructure and low level x86 glue needed for
  that, plus it adds a high level API to make use of protection keys -
  if a user-space application calls:

        mmap(..., PROT_EXEC);

  or

        mprotect(ptr, sz, PROT_EXEC);

  (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
  this special case, and will set a special protection key on this
  memory range.  It also sets the appropriate bits in the Protection
  Keys User Rights (PKRU) register so that the memory becomes unreadable
  and unwritable.

  So using protection keys the kernel is able to implement 'true'
  PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
  PROT_READ as well.  Unreadable executable mappings have security
  advantages: they cannot be read via information leaks to figure out
  ASLR details, nor can they be scanned for ROP gadgets - and they
  cannot be used by exploits for data purposes either.

  We know about no user-space code that relies on pure PROT_EXEC
  mappings today, but binary loaders could start making use of this new
  feature to map binaries and libraries in a more secure fashion.

  There is other pending pkeys work that offers more high level system
  call APIs to manage protection keys - but those are not part of this
  pull request.

  Right now there's a Kconfig that controls this feature
  (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
  (like most x86 CPU feature enablement code that has no runtime
  overhead), but it's not user-configurable at the moment.  If there's
  any serious problem with this then we can make it configurable and/or
  flip the default"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
  x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
  mm/core, x86/mm/pkeys: Add execute-only protection keys support
  x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
  x86/mm/pkeys: Allow kernel to modify user pkey rights register
  x86/fpu: Allow setting of XSAVE state
  x86/mm: Factor out LDT init from context init
  mm/core, x86/mm/pkeys: Add arch_validate_pkey()
  mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
  x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
  x86/mm/pkeys: Add Kconfig prompt to existing config option
  x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
  x86/mm/pkeys: Dump PKRU with other kernel registers
  mm/core, x86/mm/pkeys: Differentiate instruction fetches
  x86/mm/pkeys: Optimize fault handling in access_error()
  mm/core: Do not enforce PKEY permissions on remote mm access
  um, pkeys: Add UML arch_*_access_permitted() methods
  mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
  x86/mm/gup: Simplify get_user_pages() PTE bit handling
  ...
2016-03-20 19:08:56 -07:00