Commit Graph

52 Commits

Author SHA1 Message Date
Nathan Chancellor 72cf3b3df4
MIPS: vdso: Wrap -mexplicit-relocs in cc-option
Clang does not support this option and errors out:

clang-11: error: unknown argument: '-mexplicit-relocs'

Clang does not appear to need this flag like GCC does because the jalr
check that was added in commit 976c23af3e ("mips: vdso: add build
time check that no 'jalr t9' calls left") passes just fine with

$ make ARCH=mips CC=clang CROSS_COMPILE=mipsel-linux-gnu- malta_defconfig arch/mips/vdso/

even before commit d3f703c435 ("mips: vdso: fix 'jalr t9' crash in
vdso code").

-mrelax-pic-calls has been supported since clang 9, which is the
earliest version that could build a working MIPS kernel, and it is the
default for clang so just leave it be.

Fixes: d3f703c435 ("mips: vdso: fix 'jalr t9' crash in vdso code")
Link: https://github.com/ClangBuiltLinux/linux/issues/890
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
2020-02-19 10:30:10 -08:00
Victor Kamensky 976c23af3e
mips: vdso: add build time check that no 'jalr t9' calls left
vdso shared object cannot have GOT based PIC 'jalr t9' calls
because nobody set GOT table in vdso. Contributing into vdso
.o files are compiled in PIC mode and as result for internal
static functions calls compiler will generate 'jalr t9'
instructions. Those are supposed to be converted into PC
relative 'bal' calls by linker when relocation are processed.

Mips global GOT entries do have dynamic relocations and they
will be caught by cmd_vdso_check Makefile rule. Static PIC
calls go through mips local GOT entries that do not have
dynamic relocations. For those 'jalr t9' calls could be present
but without dynamic relocations and they need to be converted
to 'bal' calls by linker.

Add additional build time check to make sure that no 'jalr t9'
slip through because of some toolchain misconfiguration that
prevents 'jalr t9' to 'bal' conversion.

Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: bruce.ashfield@gmail.com
Cc: richard.purdie@linuxfoundation.org
2020-02-15 12:44:03 -08:00
Paul Burton 07015d7a10
MIPS: Disable VDSO time functionality on microMIPS
A check we're about to add to pick up on function calls that depend on
bogus use of the GOT in the VDSO picked up on instances of such function
calls in microMIPS builds. Since the code appears genuinely problematic,
and given the relatively small amount of use & testing that microMIPS
sees, go ahead & disable the VDSO for microMIPS builds.

Signed-off-by: Paul Burton <paulburton@kernel.org>
2020-02-15 12:44:03 -08:00
Victor Kamensky d3f703c435
mips: vdso: fix 'jalr t9' crash in vdso code
Observed that when kernel is built with Yocto mips64-poky-linux-gcc,
and mips64-poky-linux-gnun32-gcc toolchain, resulting vdso contains
'jalr t9' instructions in its code and since in vdso case nobody
sets GOT table code crashes when instruction reached. On other hand
observed that when kernel is built mips-poky-linux-gcc toolchain, the
same 'jalr t9' instruction are replaced with PC relative function
calls using 'bal' instructions.

The difference boils down to -mrelax-pic-calls and -mexplicit-relocs
gcc options that gets different default values depending on gcc
target triplets and corresponding binutils. -mrelax-pic-calls got
enabled by default only in mips-poky-linux-gcc case. MIPS binutils
ld relies on R_MIPS_JALR relocation to convert 'jalr t9' into 'bal'
and such relocation is generated only if -mrelax-pic-calls option
is on.

Please note 'jalr t9' conversion to 'bal' can happen only to static
functions. These static PIC calls use mips local GOT entries that
are supposed to be filled with start of DSO value by run-time linker
(missing in VDSO case) and they do not have dynamic relocations.
Global mips GOT entries must have dynamic relocations and they should
be prevented by cmd_vdso_check Makefile rule.

Solution call out -mrelax-pic-calls and -mexplicit-relocs options
explicitly while compiling MIPS vdso code. That would get correct
and consistent between different toolchains behaviour.

Reported-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: richard.purdie@linuxfoundation.org
2020-02-15 11:04:05 -08:00
Masahiro Yamada 5f2fb52fac kbuild: rename hostprogs-y/always to hostprogs/always-y
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-04 01:53:07 +09:00
Linus Torvalds c5951e7c8e The main MIPS changes for 5.6:
- Support mremap() for the VDSO, primarily to allow CRIU to restore the
   VDSO to its checkpointed location.
 
 - Restore the MIPS32 cBPF JIT, after having reverted the enablement of
   the eBPF JIT for MIPS32 systems in the 5.5 cycle.
 
 - Improve cop0 counter synchronization behaviour whilst onlining CPUs by
   running with interrupts disabled.
 
 - Better match FPU behaviour when emulating multiply-accumulate
   instructions on pre-r6 systems that implement IEEE754-2008 style MACs.
 
 - Loongson64 kernels now build using the MIPS64r2 ISA, allowing them to
   take advantage of instructions introduced by r2.
 
 - Support for the Ingenic X1000 SoC & the really nice little CU Neo
   development board that's using it.
 
 - Support for WMAC on GARDENA Smart Gateway devices.
 
 - Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
   preparation for introducing IP35 (Origin 3*) support.
 
 - Various Kconfig & Makefile cleanups.
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Merge tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS changes from Paul Burton:
 "Nothing too big or scary in here:

   - Support mremap() for the VDSO, primarily to allow CRIU to restore
     the VDSO to its checkpointed location.

   - Restore the MIPS32 cBPF JIT, after having reverted the enablement
     of the eBPF JIT for MIPS32 systems in the 5.5 cycle.

   - Improve cop0 counter synchronization behaviour whilst onlining CPUs
     by running with interrupts disabled.

   - Better match FPU behaviour when emulating multiply-accumulate
     instructions on pre-r6 systems that implement IEEE754-2008 style
     MACs.

   - Loongson64 kernels now build using the MIPS64r2 ISA, allowing them
     to take advantage of instructions introduced by r2.

   - Support for the Ingenic X1000 SoC & the really nice little CU Neo
     development board that's using it.

   - Support for WMAC on GARDENA Smart Gateway devices.

   - Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
     preparation for introducing IP35 (Origin 3*) support.

   - Various Kconfig & Makefile cleanups"

* tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (60 commits)
  MIPS: PCI: Add detection of IOC3 on IO7, IO8, IO9 and Fuel
  MIPS: Loongson64: Disable exec hazard
  MIPS: Loongson64: Bump ISA level to MIPSR2
  MIPS: Make DIEI support as a config option
  MIPS: OCTEON: octeon-irq: fix spelling mistake "to" -> "too"
  MIPS: asm: local: add barriers for Loongson
  MIPS: Loongson64: Select mac2008 only feature
  MIPS: Add MAC2008 Support
  Revert "MIPS: Add custom serial.h with BASE_BAUD override for generic kernel"
  MIPS: sort MIPS and MIPS_GENERIC Kconfig selects alphabetically (again)
  MIPS: make CPU_HAS_LOAD_STORE_LR opt-out
  MIPS: generic: don't unconditionally select PINCTRL
  MIPS: don't explicitly select LIBFDT in Kconfig
  MIPS: sync-r4k: do slave counter synchronization with disabled HW interrupts
  MIPS: SGI-IP30: Check for valid pointer before using it
  MIPS: syscalls: fix indentation of the 'SYSNR' message
  MIPS: boot: fix typo in 'vmlinux.lzma.its' target
  MIPS: fix indentation of the 'RELOCS' message
  dt-bindings: Document loongson vendor-prefix
  MIPS: CU1000-Neo: Refresh defconfig to support HWMON and WiFi.
  ...
2020-01-31 11:28:31 -08:00
Thomas Gleixner 99570c3da9 MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel
The confinement of the 32bit specific VDSO functions missed to define
BUILD_VDSO32 when building a 32bit MIPS kernel:

arch/mips/vdso/vgettimeofday.c: In function __vdso_clock_gettime:
arch/mips/vdso/vgettimeofday.c:17:9: error: implicit declaration of function __cvdso_clock_gettime32

arch/mips/vdso/vgettimeofday.c: In function __vdso_clock_getres:
arch/mips/vdso/vgettimeofday.c:39:9: error: implicit declaration of function __cvdso_clock_getres_time32

Force the define for 32bit builds in the VDSO Makefile.

Fixes: bf279849ad ("lib/vdso: Build 32 bit specific functions in the right context")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul Burton <paulburton@kernel.org>
Link: https://lore.kernel.org/r/87d0bjfaqa.fsf@nanos.tec.linutronix.de
2020-01-16 21:24:25 +01:00
Guoyun Sun ad1df95419
mips/vdso: Support mremap() for vDSO
vDSO VMA address is saved in mm_context for the purpose of using
restorer from vDSO page to return to userspace after signal handling.

In Checkpoint Restore in Userspace (CRIU) project we place vDSO VMA
on restore back to the place where it was on the dump.

Make vDSO code track the VMA address by supplying .mremap() fops
the same way it's done for x86 and arm by:
commit b059a453b1 ("x86/vdso: Add mremap hook to vm_special_mapping")
commit 739586951b ("arm64/vdso: Support mremap() for vDSO").

Signed-off-by: Guoyun Sun <sunguoyun@loongson.cn>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Allison Randal <allison@lohutok.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2020-01-15 10:44:14 -08:00
Vincenzo Frascino 7d2aa4bb90
mips: Fix gettimeofday() in the vdso library
The libc provides a discovery mechanism for vDSO library and its
symbols. When a symbol is not exposed by the vDSOs the libc falls back
on the system calls.

With the introduction of the unified vDSO library on mips this behavior
is not honored anymore by the kernel in the case of gettimeofday().

The issue has been noticed and reported due to a dhclient failure on the
CI20 board:

root@letux:~# dhclient
../../../../lib/isc/unix/time.c:200: Operation not permitted
root@letux:~#

Restore the original behavior fixing gettimeofday() in the vDSO library.

Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com> # CI20 with JZ4780
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: mips-creator-ci20-dev@googlegroups.com
Cc: letux-kernel@openphoenux.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-12-02 10:50:37 -08:00
Alexey Khoroshilov dcf78ee660
MIPS: allow building with kcov coverage
Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to MIPS config.
Disable instrumentation of vdso to avoid build failure.

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-11-11 10:46:53 -08:00
Paul Burton 2f2b4fd674
MIPS: Disable Loongson MMI instructions for kernel build
GCC 9.x automatically enables support for Loongson MMI instructions when
using some -march= flags, and then errors out when -msoft-float is
specified with:

  cc1: error: ‘-mloongson-mmi’ must be used with ‘-mhard-float’

The kernel shouldn't be using these MMI instructions anyway, just as it
doesn't use floating point instructions. Explicitly disable them in
order to fix the build with GCC 9.x.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 3702bba5eb ("MIPS: Loongson: Add GCC 4.4 support for Loongson2E")
Fixes: 6f7a251a25 ("MIPS: Loongson: Add basic Loongson 2F support")
Fixes: 5188129b8c ("MIPS: Loongson-3: Improve -march option and move it to Platform")
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: stable@vger.kernel.org # v2.6.32+
Cc: linux-mips@vger.kernel.org
2019-10-10 11:58:52 -07:00
Paul Burton 8919975b61
MIPS: VDSO: Fix build for binutils < 2.25
Versions of binutils prior to 2.25 are unable to link our VDSO due to an
unsupported R_MIPS_PC32 relocation generated by the ".word _start - ."
line of the inline asm in get_vdso_base(). As such, the intent is that
when building with binutils older than 2.25 we don't build code for
gettimeofday() & friends in the VDSO that rely upon get_vdso_base().

Commit 24640f233b ("mips: Add support for generic vDSO") converted us
to using generic VDSO infrastructure, and as part of that the
gettimeofday() functionality moved to a new vgettimeofday.c file. The
check for binutils < 2.25 wasn't updated to handle this new filename,
and so it continues trying to remove the old unused filename from the
build. The end result is that we try to include the gettimeofday() code
in builds that will fail to link.

Fix this by updating the binutils < 2.25 case to remove vgettimeofday.c
from obj-vdso-y, rather than gettimeofday.c.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 24640f233b ("mips: Add support for generic vDSO")
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-mips@vger.kernel.org
2019-10-02 14:07:32 -07:00
Paul Burton 90800281e7
MIPS: VDSO: Remove unused gettimeofday.c
arch/mips/vdso/gettimeofday.c has been unused since commit 24640f233b
("mips: Add support for generic vDSO"). Remove the dead code.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 24640f233b ("mips: Add support for generic vDSO")
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-mips@vger.kernel.org
2019-10-02 14:07:30 -07:00
Vincenzo Frascino 932bb934ed
mips: compat: vdso: Use legacy syscalls as fallback
The generic VDSO implementation uses the Y2038 safe clock_gettime64() and
clock_getres_time64() syscalls as fallback for 32bit VDSO. This breaks
seccomp setups because these syscalls might be not (yet) allowed.

Implement the 32bit variants which use the legacy syscalls and select the
variant in the core library.

The 64bit time variants are not removed because they are required for the
time64 based vdso accessors.

Cc: Paul Burton <paul.burton@mips.com>
Fixes: 00b26474c2 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: catalin.marinas@arm.com
Cc: will@kernel.org
Cc: tglx@linutronix.de
Cc: salyzyn@android.com
Cc: 0x7f454c46@gmail.com
Cc: luto@kernel.org
2019-09-03 15:35:23 +01:00
Arnd Bergmann 6393e60644
mips: fix vdso32 build, again
The generic vdso support adds the same #if hack in two places,
asm/vdso/vdso.h and config-n32-o32-env.c, but only the second
is actually used. The result lacks the BUILD_VDSO32_64 macro,
and that triggers a build error:

./include/linux/page-flags-layout.h:95:2: error: #error "Not enough bits in page flags"

Move the macro into the other place, and remove the duplicated
bits.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Fixes: ee38d94a0a ("page flags: prioritize kasan bits over last-cpuid")
Fixes: 24640f233b ("mips: Add support for generic vDSO")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-08-06 14:32:15 -07:00
Vincenzo Frascino cdab7e2c73
mips: vdso: Fix flip/flop vdso building bug
Running "make" on an already compiled kernel tree will rebuild the
vdso library even if this has not been modified.

$ make
  GEN     Makefile
  Using linux as source for kernel
  CALL   linux/scripts/atomic/check-atomics.sh
  CALL   linux/scripts/checksyscalls.sh
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]
  CHK     include/generated/compile.h
  VDSO    arch/mips/vdso/vdso.so.dbg.raw
  OBJCOPY arch/mips/vdso/vdso.so.raw
  GENVDSO arch/mips/vdso/vdso-image.c
  CC      arch/mips/vdso/vdso-image.o
  AR      arch/mips/vdso/built-in.a
  AR      arch/mips/built-in.a
  CHK     include/generated/autoksyms.h
  GEN     .version
  CHK     include/generated/compile.h
  UPD     include/generated/compile.h
  CC      init/version.o
  AR      init/built-in.a
  LD      vmlinux.o
  MODPOST vmlinux.o
  MODINFO modules.builtin.modinfo
  KSYM    .tmp_kallsyms1.o
  KSYM    .tmp_kallsyms2.o
  LD      vmlinux
  SORTEX  vmlinux
  SYSMAP  System.map
  Building modules, stage 2.
  ITS     arch/mips/boot/vmlinux.gz.its
  OBJCOPY arch/mips/boot/vmlinux.bin
  MODPOST 7 modules
  GZIP    arch/mips/boot/vmlinux.bin.gz
  ITB     arch/mips/boot/vmlinux.gz.itb

The issue is generated by the fact that "if_changed" is called twice
in a single target.

Fix the build bug merging the two commands into a single function.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-07-26 16:43:38 -07:00
Vincenzo Frascino b4c0f7fa53
mips: vdso: Fix source path
The vdso library for o32 and n32 does not compile compile correctly when
building outside of the source tree due to a wrong inclusion path for
config-n32-o32-env.c resulting in the error below:

cc1: fatal error: arch/mips/vdso/config-n32-o32-env.c:
No such file or dnirectory
compilation terminated.
arch/mips/vdso/Makefile:153: recipe for target
'arch/mips/vdso/vgettimeofday-o32.o' failed
make[3]: *** [arch/mips/vdso/vgettimeofday-o32.o] Error 1
scripts/Makefile.build:490: recipe for target 'arch/mips/vdso' failed

Fix the config-n32-o32-env.c inclusion path prepending the $(srctree)
variable.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[paul.burton@mips.com: Note that this occurs specifically when building
                       outside of the source tree.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-07-26 16:42:27 -07:00
Vincenzo Frascino 1f66c45db3
mips: Add clock_gettime64 entry point
With the release of Linux 5.1 has been added a new syscall,
clock_gettime64, that provided a 64 bit time value for a specified
clock_ID to make the kernel Y2038 safe on 32 bit architectures.

Update the mips32 specific vDSO library accordingly with what it has
been done for the kernel syscall exposing the clock_gettime64 entry
point.

Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-07-25 21:45:52 -07:00
Vincenzo Frascino abed3d826f
mips: Add clock_getres entry point
The generic vDSO library provides an implementation of clock_getres()
that can be leveraged by each architecture.

Add clock_getres() entry point on mips.

Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-07-25 21:45:35 -07:00
Vincenzo Frascino 24640f233b
mips: Add support for generic vDSO
The mips vDSO library requires some adaptations to take advantage of the
newly introduced generic vDSO library.

Introduce the following changes:
 - Modification of vdso.c to be compliant with the common vdso datapage
 - Use of lib/vdso for gettimeofday

Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[paul.burton@mips.com: Prepend $(src) to config-n32-o32-env.c path.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-07-25 21:45:05 -07:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Nick Desaulniers 1e0221374e
mips: vdso: drop unnecessary cc-ldoption
Towards the goal of removing cc-ldoption, it seems that --hash-style=
was added to binutils 2.17.50.0.2 in 2006. The minimal required version
of binutils for the kernel according to
Documentation/process/changes.rst is 2.20.

--build-id was added in 2.18 according to binutils-gdb/ld/NEWS.

Link: https://gcc.gnu.org/ml/gcc/2007-01/msg01141.html
Cc: clang-built-linux@googlegroups.com
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: ralf@linux-mips.org
Cc: jhogan@kernel.org
Cc: Matt Redfearn <matt.redfearn@mips.com>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Hassan Naveed <hnaveed@wavecomp.com>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-04-23 14:53:54 -07:00
Paul Burton 67fc5dc8a5
MIPS: VDSO: Include $(ccflags-vdso) in o32,n32 .lds builds
When generating vdso-o32.lds & vdso-n32.lds for use with programs
running as compat ABIs under 64b kernels, we previously haven't included
the compiler flags that are supposedly common to all ABIs - ie. those in
the ccflags-vdso variable.

This is problematic in cases where we need to provide the -m%-float flag
in order to ensure that we don't attempt to use a floating point ABI
that's incompatible with the target CPU & ABI. For example a toolchain
using current gcc trunk configured --with-fp-32=xx fails to build a
64r6el_defconfig kernel with the following error:

  cc1: error: '-march=mips1' requires '-mfp32'
  make[2]: *** [arch/mips/vdso/Makefile:135: arch/mips/vdso/vdso-o32.lds] Error 1

Include $(ccflags-vdso) for the compat VDSO .lds builds, just as it is
included for the native VDSO .lds & when compiling objects for the
compat VDSOs. This ensures we consistently provide the -msoft-float flag
amongst others, avoiding the problem by ensuring we're agnostic to the
toolchain defaults.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
Cc: linux-mips@vger.kernel.org
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Maciej W . Rozycki <macro@linux-mips.org>
Cc: stable@vger.kernel.org # v4.4+
2019-01-29 11:50:58 -08:00
Paul Burton 0648e50e54
MIPS: VDSO: Use same -m%-float cflag as the kernel proper
The MIPS VDSO build currently doesn't provide the -msoft-float flag to
the compiler as the kernel proper does. This results in an attempt to
use the compiler's default floating point configuration, which can be
problematic in cases where this is incompatible with the target CPU's
-march= flag. For example decstation_defconfig fails to build using
toolchains in which gcc was configured --with-fp-32=xx with the
following error:

    LDS     arch/mips/vdso/vdso.lds
  cc1: error: '-march=r3000' requires '-mfp32'
  make[2]: *** [scripts/Makefile.build:379: arch/mips/vdso/vdso.lds] Error 1

The kernel proper avoids this error because we build with the
-msoft-float compiler flag, rather than using the compiler's default.
Pass this flag through to the VDSO build so that it too becomes agnostic
to the toolchain's floating point configuration.

Note that this is filtered out from KBUILD_CFLAGS rather than simply
always using -msoft-float such that if we switch the kernel to use
-mno-float in the future the VDSO will automatically inherit the change.

The VDSO doesn't actually include any floating point code, and its
.MIPS.abiflags section is already manually generated to specify that
it's compatible with any floating point ABI. As such this change should
have no effect on the resulting VDSO, apart from fixing the build
failure for affected toolchains.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Kevin Hilman <khilman@baylibre.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Kevin Hilman <khilman@baylibre.com>
References: https://lore.kernel.org/linux-mips/1477843551-21813-1-git-send-email-linux@roeck-us.net/
References: https://kernelci.org/build/id/5c4e4ae059b5142a249ad004/logs/
Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v4.4+
2019-01-29 11:50:41 -08:00
Hassan Naveed 1e35918ad9
MIPS: Enable Undefined Behavior Sanitizer UBSAN
Select ARCH_HAS_UBSAN_SANITIZE_ALL in order to allow the user to
enable CONFIG_UBSAN_SANITIZE_ALL and instrument the entire kernel for
ubsan checks.
We exclude the VDSO from this because its build doesn't include the
__ubsan_handle_*() functions that the kernel proper defines in from
lib/ubsan.c, and the VDSO would have no sane way to report errors even
if it had definitions of these functions.

Signed-off-by: Hassan Naveed <hnaveed@wavecomp.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21179/
Cc: <linux-mips@linux-mips.org>
2018-11-20 12:23:06 -08:00
Masahiro Yamada 076f421da5 kbuild: replace cc-name test with CONFIG_CC_IS_CLANG
Evaluating cc-name invokes the compiler every time even when you are
not compiling anything, like 'make help'. This is not efficient.

The compiler type has been already detected in the Kconfig stage.
Use CONFIG_CC_IS_CLANG, instead.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Paul Burton <paul.burton@mips.com> (MIPS)
Acked-by: Joel Stanley <joel@jms.id.au>
2018-11-02 22:49:00 +09:00
Paul Burton 2f0025675f
MIPS: VDSO: Force link endianness
When building the VDSO with clang it appears to invoke ld without
specifying endianness, even though clang itself was provided with a -EB
or -EL flag. This results in the build failing due to a mismatch between
the objects that are the input to ld, and the output it is attempting to
create:

  VDSO    arch/mips/vdso/vdso.so.dbg.raw
  mips-linux-ld: arch/mips/vdso/elf.o: compiled for a big endian system
    and target is little endian
  mips-linux-ld: arch/mips/vdso/elf.o: endianness incompatible with that
    of the selected emulation
  mips-linux-ld: failed to merge target specific data of file
    arch/mips/vdso/elf.o
  ...

Work around this problem by explicitly specifying the link endianness
using -Wl,-EB or -Wl,-EL when -EB or -EL are part of KBUILD_CFLAGS. This
resolves the build failure when using clang, and doesn't have any
negative effect on gcc.

Signed-off-by: Paul Burton <paul.burton@mips.com>
2018-08-07 16:16:13 -07:00
Paul Burton ee67855ecd
MIPS: vdso: Allow clang's --target flag in VDSO cflags
The MIPS VDSO code filters out a subset of known-good flags from
KBUILD_CFLAGS to use when building VDSO libraries. When we build using
clang we need to allow the --target flag through, otherwise we'll
generally attempt to build the VDSO for the architecture of the build
machine rather than for MIPS.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20154/
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
2018-08-06 15:53:33 -07:00
Paul Burton 4467f7ad7d
MIPS: genvdso: Remove GOT checks
Our genvdso tool performs some rather paranoid checking that the VDSO
library isn't attempting to make use of a GOT by constraining the number
of entries that the GOT is allowed to contain to the minimum 2 entries
that are always generated by binutils.

Unfortunately lld prior to revision 334390 generates a third entry,
which is unused & thus harmless but falls foul of genvdso's checks &
causes the build to fail.

Since we already check that the VDSO contains no relocations it seems
reasonable to presume that it also doesn't contain use of a GOT, which
would involve relocations. Thus rather than attempting to work around
this issue by allowing 3 GOT entries when using lld, simply remove the
GOT checks which seem overly paranoid.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20152/
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
2018-08-06 15:28:46 -07:00
Paul Burton 351fdddd36
MIPS: VDSO: Prevent use of smp_processor_id()
VDSO code should not be using smp_processor_id(), since it is executed
in user mode.
Introduce a VDSO-specific path which will cause a compile-time
or link-time error (depending upon support for __compiletime_error) if
the VDSO ever incorrectly attempts to use smp_processor_id().

[Matt Redfearn <matt.redfearn@imgtec.com>: Move before change to
smp_processor_id in series]

Signed-off-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/17932/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
2018-07-27 19:36:16 -07:00
Matt Redfearn ce6828faeb
MIPS: VDSO: Replace __mips_isa_rev with MIPS_ISA_REV
Remove the need to check that __mips_isa_rev is defined by using the
newly added MIPS_ISA_REV.

Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18678/
Signed-off-by: James Hogan <jhogan@kernel.org>
2018-03-09 11:22:48 +00:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Corey Minyard 866b6a89c6 MIPS: Add DWARF unwinding to assembly
This will allow kdump dumps to work correclty with MIPS and
future DWARF unwinding of the stack to give accurate tracebacks.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16990/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06 11:01:52 +02:00
Paul Burton 16ae123e89 MIPS: VDSO: Avoid use of linux/irqchip/mips-gic.h
Our VDSO code makes use of macros from linux/irqchip/mips-gic.h to
provide offsets to register values, but these are trivial offsets to the
two 32 bit halves of a 64 bit value. Replace use of the macros with zero
(ie. omit adding an offset) and the size of the low 32 bit of the value.
This removes our need for linux/irqchip/mips-gic.h & prepares us for it
to be removed.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17047/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04 13:53:14 +02:00
Paul Burton e83f7e02af MIPS: CPS: Have asm/mips-cps.h include CM & CPC headers
With Coherence Manager (CM) 3.5 information about the topology of the
system, which has previously only been available through & accessed from
the CM, is now also provided by the Cluster Power Controller (CPC). This
includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a
new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG.

In preparation for adjusting functions such as mips_cm_numcores(), which
have previously only needed to access the CM, to also access the CPC
this patch modifies the way we use the various CPS headers. Rather than
having users include asm/mips-cm.h or asm/mips-cpc.h individually we
instead have users include asm/mips-cps.h which in turn includes
asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access
to both CM & CPC registers by including one header, and most importantly
it makes asm/mips-cps.h an ideal location for helper functions which
need to access the various components of the CPS.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17015/
Patchwork: https://patchwork.linux-mips.org/patch/17217/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30 00:57:27 +02:00
Goran Ferenc b399ee28c2 MIPS: VDSO: Fix clobber lists in fallback code paths
Extend clobber lists to include all GP registers.

Fixes: 0b523a85e1 ("MIPS: VDSO: Add implementation of gettimeofday() fallback")

Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Bo Hu <bohu@google.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jin Qian <jinqian@google.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16879/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-07 13:53:25 +02:00
Aleksandar Markovic bdb94f6e82 MIPS: VDSO: Fix a mismatch between comment and preprocessor constant
Sync the comment with its preprocessor constant counterpart.

Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Miodrag Dinic <miodrag.dinic@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16641/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-29 02:42:30 +02:00
Goran Ferenc 0b523a85e1 MIPS: VDSO: Add implementation of gettimeofday() fallback
This patch adds gettimeofday_fallback() function that wraps assembly
invocation of gettimeofday() syscall using __NR_gettimeofday.

This function is used if pure VDSO implementation gettimeofday()
does not succeed for any reason. Its imeplementation is enclosed in
"#ifdef CONFIG_MIPS_CLOCK_VSYSCALL" to be in sync with the similar
arrangement for __vdso_gettimeofday().

If syscall invocation via __NR_gettimeofday fails, register a3 will
be set. So, after the syscall, register a3 is tested and the return
valuem is negated if it's set.

Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16640/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-29 02:42:30 +02:00
Goran Ferenc 180902e08f MIPS: VDSO: Add implementation of clock_gettime() fallback
This patch adds clock_gettime_fallback() function that wraps assembly
invocation of clock_gettime() syscall using __NR_clock_gettime.

This function is used if pure VDSO implementation of clock_gettime()
does not succeed for any reason. For example, it is called if the
clkid parameter of clock_gettime() is not one of the clkids listed
in the switch-case block of the function __vdso_clock_gettime()
(one such case for clkid is CLOCK_BOOTIME).

If syscall invocation via __NR_clock_gettime fails, register a3 will
be set. So, after the syscall, register a3 is tested and the return
value is negated if it's set.

Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16639/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-29 02:42:29 +02:00
Goran Ferenc 8ec7f15b8c MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse()
Fix incorrect calculation in do_monotonic() and do_monotonic_coarse()
function that in turn caused incorrect values returned by the vdso
version of system call clock_gettime() on mips64 if its system clock
ID parameter was CLOCK_MONOTONIC or CLOCK_MONOTONIC_COARSE.

Consider these variables and their types on mips32 and mips64:

tk->wall_to_monotonic.tv_sec  s64, s64   (kernel/vdso.c)
vdso_data.wall_to_mono_sec    u32, u32   (kernel/vdso.c)
to_mono_sec                   u32, u32   (vdso/gettimeofday.c)
ts->tv_sec                    s32, s64   (vdso/gettimeofday.c)

For mips64 case, u32 vdso_data.wall_to_mono_sec variable is updated
from the 64-bit signed variable tk->wall_to_monotonic.tv_sec
(kernel/vdso.c:76) which is a negative number holding the time passed
from 1970-01-01 to the time boot started. This 64-bit signed value is
currently around 47+ years, in seconds. For instance, let this value
be:

-1489757461

or

11111111111111111111111111111111 10100111001101000001101011101011

By updating 32-bit vdso_data.wall_to_mono_sec variable, we lose upper
32 bits (signed 1's).

to_mono_sec variable is a parameter of do_monotonic() and
do_monotonic_coarse() functions which holds vdso_data.wall_to_mono_sec
value. Its value needs to be added (or subtracted considering it holds
negative value from the tk->wall_to_monotonic.tv_sec) to the current
time passed from 1970-01-01 (ts->tv_sec), which is again something like
47+ years, but increased by the time passed from the boot to the
current time. ts->tv_sec is 32-bit long in case of 32-bit architecture
and 64-bit long in case of 64-bit architecture. Consider the update of
ts->tv_sec (vdso/gettimeofday.c:55 & 167):

ts->tv_sec += to_mono_sec;

mips32 case: This update will be performed correctly, since both
ts->tv_sec and to_mono_sec are 32-bit long and the sign in to_mono_sec
is preserved. Implicit conversion from u32 to s32 will be done
correctly.

mips64 case: This update will be wrong, since the implicit conversion
will not be done correctly. The reason is that the conversion will be
from u32 to s64. This is because to_mono_sec is 32-bit long for both
mips32 and mips64 cases and s64..33 bits of converted to_mono_sec
variable will be zeros.

So, in order to make MIPS64 implementation work properly for
MONOTONIC and MONOTONIC_COARSE clock ids on mips64, the size of
wall_to_mono_sec variable in mips_vdso_data union and respective
parameters in do_monotonic() and do_monotonic_coarse() functions
should be changed from u32 to u64. Because of consistency, this
size change from u32 and u64 is also done for wall_to_mono_nsec
variable and corresponding function parameters.

As far as similar situations for other architectures are concerned,
let's take a look at arm. Arm has two distinct vdso_data structures
for 32-bit & 64-bit cases, and arm's wall_to_mono_sec and
wall_to_mono_nsec are u32 for 32-bit and u64 for 64-bit cases.
On the other hand, MIPS has only one structure (mips_vdso_data),
hence the need for changing the size of above mentioned parameters.

Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16638/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-29 02:42:29 +02:00
Robert Schiele cfd75c2db1 MIPS: VDSO: Explicitly use -fno-asynchronous-unwind-tables
Not every toolchain has -fno-asynchronous-unwind-tables per default on
MIPS. This patch specifies the necessary option explicitly for VDSO
library build.

This prevents the following build failure:
GENVDSO arch/mips/vdso/vdso-image.c
arch/mips/vdso/genvdso: 'arch/mips/vdso/vdso.so.dbg' contains relocation sections
.../arch/mips/vdso/Makefile:84: recipe for target 'arch/mips/vdso/vdso-image.c' failed

Signed-off-by: Robert Schiele <rschiele@gmail.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "Maciej W. Rozycki" <macro@imgtec.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15127/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2017-02-17 11:32:12 +00:00
Arnd Bergmann b668970e61 MIPS: Fix modversions
kernelci.org reports tons of build warnings for linux-next:

35	WARNING: "memcpy" [fs/fat/msdos.ko] has no CRC!
35	WARNING: "__copy_user" [fs/fat/fat.ko] has no CRC!
32	WARNING: EXPORT symbol "memset" [vmlinux] version generation failed, symbol will not be versioned.
32	WARNING: EXPORT symbol "copy_page" [vmlinux] version generation failed, symbol will not be versioned.
32	WARNING: EXPORT symbol "clear_page" [vmlinux] version generation failed, symbol will not be versioned.
32	WARNING: EXPORT symbol "__strncpy_from_user_nocheck_asm" [vmlinux] version generation failed, symbol will not be versioned.

The problem here is mainly the missing asm/asm-prototypes.h header file
that is supposed to include the prototypes for each symbol that is exported
from an assembler file.

A second problem is that the asm/uaccess.h header contains some but not
all the necessary declarations for the user access helpers.

Finally, the vdso build is broken once we add asm/asm-prototypes.h, so
we have to fix this at the same time by changing the vdso header. My
approach here is to just not look for exported symbols in the VDSO
assembler files, as the symbols cannot be exported anyway.

Fixes: 576a2f0c5c ("MIPS: Export memcpy & memset functions alongside their definitions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15038/
Patchwork: https://patchwork.linux-mips.org/patch/15069/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-01-24 18:30:35 +01:00
James Hogan 9445622cfb MIPS: VDSO: Drop duplicated -I*/-E* aflags
The aflags-vdso is based on ccflags-vdso, which already contains the -I*
and -EL/-EB flags from KBUILD_CFLAGS, but those flags are needlessly
added again to aflags-vdso.

Drop the duplication.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reported-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14369/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-11 15:07:30 +02:00
James Hogan 034827c727 MIPS: Fix -mabi=64 build of vdso.lds
The native ABI vDSO linker script vdso.lds is built by preprocessing
vdso.lds.S, with the native -mabi flag passed in to get the correct ABI
definitions. Unfortunately however certain toolchains choke on -mabi=64
without a corresponding compatible -march flag, for example:

cc1: error: ‘-march=mips32r2’ is not compatible with the selected ABI
scripts/Makefile.build:338: recipe for target 'arch/mips/vdso/vdso.lds' failed

Fix this by including ccflags-vdso in the KBUILD_CPPFLAGS for vdso.lds,
which includes the appropriate -march flag.

Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.4.x-
Patchwork: https://patchwork.linux-mips.org/patch/14368/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-11 15:03:47 +02:00
James Hogan bb93078e65 MIPS: Build microMIPS VDSO for microMIPS kernels
MicroMIPS kernels may be expected to run on microMIPS only cores which
don't support the normal MIPS instruction set, so be sure to pass the
-mmicromips flag through to the VDSO cflags.

Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
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> # 4.4.x-
Patchwork: https://patchwork.linux-mips.org/patch/13349/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-28 12:35:12 +02:00
Maciej W. Rozycki 94cc36b84a MIPS: VDSO: Build with `-fno-strict-aliasing'
Avoid an aliasing issue causing a build error in VDSO:

In file included from include/linux/srcu.h:34:0,
                 from include/linux/notifier.h:15,
                 from ./arch/mips/include/asm/uprobes.h:9,
                 from include/linux/uprobes.h:61,
                 from include/linux/mm_types.h:13,
                 from ./arch/mips/include/asm/vdso.h:14,
                 from arch/mips/vdso/vdso.h:27,
                 from arch/mips/vdso/gettimeofday.c:11:
include/linux/workqueue.h: In function 'work_static':
include/linux/workqueue.h:186:2: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
  return *work_data_bits(work) & WORK_STRUCT_STATIC;
  ^
cc1: all warnings being treated as errors
make[2]: *** [arch/mips/vdso/gettimeofday.o] Error 1

with a CONFIG_DEBUG_OBJECTS_WORK configuration and GCC 5.2.0.  Include
`-fno-strict-aliasing' along with compiler options used, as required for
kernel code, fixing a problem present since the introduction of VDSO
with commit ebb5e78cc6 ("MIPS: Initial implementation of a VDSO").

Thanks to Tejun for diagnosing this properly!

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Fixes: ebb5e78cc6 ("MIPS: Initial implementation of a VDSO")
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.3+
Patchwork: https://patchwork.linux-mips.org/patch/13357/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-28 12:35:12 +02:00
James Hogan 2afb974543 MIPS: Fix genvdso error on rebuild
The genvdso program modifies the debug and stripped versions of the
VDSOs in place, and errors if the modification has already taken place.
Unfortunately this means that a rebuild which tries to rerun genvdso to
generate vdso*-image.c without also rebuilding vdso.so.dbg (for example
if genvdso.c is modified) hits a build error like this:

arch/mips/vdso/genvdso 'arch/mips/vdso/vdso.so.dbg' already contains a '.MIPS.abiflags' section

This is fixed by reorganising the rules such that unmodified .so files
have a .raw suffix, and these are copied in the same rule that runs
genvdso on the copies.

I.e. previously we had:

 cmd_vdsold:
  link objects -> vdso.so.dbg

 cmd_genvdso:
  strip vdso.so.dbg -> vdso.so
  run genvdso -> vdso-image.c
   and modify vdso.so.dbg and vdso.so in place

Now we have:

 cmd_vdsold:
  link objects -> vdso.so.dbg.raw

 a new cmd_objcopy based strip rule (inspired by ARM):
  strip vdso.so.dbg.raw -> vdso.so.raw

 cmd_genvdso:
  copy vdso.so.dbg.raw -> vdso.so.dbg
  copy vdso.so.raw -> vdso.so
  run genvdso -> vdso-image.c
   and modify vdso.so.dbg and vdso.so in place

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13250/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 22:47:39 +02:00
James Hogan d5ece1cb07 Fix ld-version.sh to handle large 3rd version part
The ld-version.sh script doesn't handle versions with large (>= 10) 3rd
version components, because the 2nd component is only multiplied by 10
times that of the 3rd component.

For example the following version string:
GNU ld (Codescape GNU Tools 2015.06-05 for MIPS MTI Linux) 2.24.90

gives a bogus version number:
 20000000
+ 2400000
+  900000 = 23300000

Breakage, confusion and mole-whacking ensues.

Increase the multipliers of the first two version components by a factor
of 10 to give space for a 3rd components of up to 99, and update the
sole user of ld-ifversion (MIPS VDSO) accordingly.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11931/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-04 10:22:52 +01:00
Guenter Roeck 398c7500a1 MIPS: VDSO: Fix build error with binutils 2.24 and earlier
Commit 2a037f310b ("MIPS: VDSO: Fix build error") tries to fix a build
error seen with binutils 2.24 and earlier. However, the fix does not work,
and again results in the already known build errors if the kernel is built
with an earlier version of binutils.

CC      arch/mips/vdso/gettimeofday.o
/tmp/ccnOVbHT.s: Assembler messages:
/tmp/ccnOVbHT.s:50: Error: can't resolve `_start' {*UND* section} - `L0 {.text section}
/tmp/ccnOVbHT.s:374: Error: can't resolve `_start' {*UND* section} - `L0 {.text section}
scripts/Makefile.build:258: recipe for target 'arch/mips/vdso/gettimeofday.o' failed
make[2]: *** [arch/mips/vdso/gettimeofday.o] Error 1

Fixes: 2a037f310b ("MIPS: VDSO: Fix build error")
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11926/
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-12-29 23:41:55 +01:00
Qais Yousef 2a037f310b MIPS: VDSO: Fix build error
Commit ebb5e78cc6 ("MIPS: Initial implementation of a VDSO") introduced a
build error.

For MIPS VDSO to be compiled it requires binutils version 2.25 or above but
the check in the Makefile had inverted logic causing it to be compiled in if
binutils is below 2.25.

This fixes the following compilation error:

CC      arch/mips/vdso/gettimeofday.o
/tmp/ccsExcUd.s: Assembler messages:
/tmp/ccsExcUd.s:62: Error: can't resolve `_start' {*UND* section} - `L0' {.text section}
/tmp/ccsExcUd.s:467: Error: can't resolve `_start' {*UND* section} - `L0' {.text section}
make[2]: *** [arch/mips/vdso/gettimeofday.o] Error 1
make[1]: *** [arch/mips/vdso] Error 2
make: *** [arch/mips] Error 2

[ralf@linux-mips: Fixed Sergei's complaint on the formatting of the
cited commit and generally reformatted the log message.]

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: alex@alex-smith.me.uk
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11745/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-12-22 12:23:31 +01:00