Commit Graph

1906 Commits

Author SHA1 Message Date
Andrew Bresticker
a669efc4a3 MIPS: Add hook to get C0 performance counter interrupt
The hardware perf event driver and oprofile interpret the global
cp0_perfcount_irq differently: in the hardware perf event driver
it is an offset from MIPS_CPU_IRQ_BASE and in oprofile it is the
actual IRQ number.  This still works most of the time since
MIPS_CPU_IRQ_BASE is usually 0, but is clearly wrong.  Since the
performance counter interrupt may vary from platform to platform
like the C0 timer interrupt, add the optional get_c0_perfcount_int
hook which returns the IRQ number of the performance counter.
The hook should return < 0 if the performance counter interrupt is
shared with the timer.  If the hook is not present, the CPU vector
reported in C0_IntCtl (cp0_perfcount_irq) is used.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7805/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:53 +01:00
Andrew Bresticker
079a460176 MIPS: i8259: Use IRQ domains
Create a legacy IRQ domain for the 16 i8259 interrupts.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7804/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker
f64e55dcbf MIPS: Set vint handler when mapping CPU interrupts
When mapping an interrupt in the CPU IRQ domain, set the vint handler
for that interrupt if the CPU uses vectored interrupt handling.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7802/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker
85f7cdacbb MIPS: Provide a generic plat_irq_dispatch
For platforms which boot with device-tree or have correctly chained
all external interrupt controllers, a generic plat_irq_dispatch() can
be used.  Implement a plat_irq_dispatch() which simply handles all the
pending interrupts as reported by C0_Cause.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7801/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker
afe8dc2547 MIPS: Rename mips_cpu_intc_init() -> mips_cpu_irq_of_init()
mips_cpu_intc_init() is used for DT-based initialization of the CPU
IRQ domain.  Give it a more appropriate name.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7800/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker
0f84c30535 MIPS: Always use IRQ domains for CPU IRQs
Use an IRQ domain for the 8 CPU IRQs in both the DT and non-DT cases.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7799/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Markos Chandras
97f4ad29da MIPS: cpu: Add 'noftlb' kernel command line option to disable the FTLB
Add new 'noftlb' kernel command line option to disable the FTLB.
Since the kernel command line is not available when probing and
enabling the CPU features in cpu_probe(), we let the kernel configure
the FTLB during the config4 decode operation and we disable the FTLB later
on, once the command line has become available to us. This should have
no negative effects since FTLB isn't used so early in the boot process.
FTLB increases the effective TLB size leading to less TLB misses. However,
sometimes it's useful to be able to disable it when debugging memory related
core features or other hardware components.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/7586/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Joe Perches
7178d2cdd9 mips: Convert pr_warning to pr_warn
Use the much more common pr_warn instead of pr_warning
with the goal of removing pr_warning eventually.

Other miscellanea:

o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/7935/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Eunbong Song
856839b768 MIPS: Add arch_trigger_all_cpu_backtrace() function
Currently, arch_trigger_all_cpu_backtrace() is defined in only x86 and
sparc which have an NMI.  But in case of softlockup, it could be possible
to dump backtrace of all cpus. and this could be helpful for debugging.

for example, if system has 2 cpus.

	CPU 0				CPU 1
 acquire read_lock()

				try to do write_lock()

 ,,,
 missing read_unlock()

In this case, softlockup will occur becasuse CPU 0 does not call
read_unlock().  And dump_stack() print only backtrace for "CPU 0". If
CPU1's backtrace is printed it's very helpful.

[ralf@linux-mips.org: Fixed whitespace and formatting issues.]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8200/
2014-11-24 07:44:49 +01:00
Ralf Baechle
635c990706 MIPS: Remove useless parentheses
Based on the spatch

@@
expression e;
@@
- return (e);
+ return e;

with heavy hand editing because some of the changes are either whitespace
or identation only or result in excessivly long lines.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:49 +01:00
Maciej W. Rozycki
935c2dbec4 MIPS: jump_label.c: Handle the microMIPS J instruction encoding
Implement the microMIPS encoding of the J instruction for the purpose of
the static keys feature, fixing a crash early on in bootstrap as the
kernel is unhappy seeing the ISA bit set in jump table entries.  Make
sure the ISA bit correctly reflects the instruction encoding chosen for
the kernel, 0 for the standard MIPS and 1 for the microMIPS encoding.

Also make sure the instruction to patch is a 32-bit NOP in the microMIPS
mode as by default the 16-bit short encoding is assumed

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8516/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:09 +01:00
Maciej W. Rozycki
99436f7d69 MIPS: jump_label.c: Correct the span of the J instruction
Correct the check for the span of the 256MB segment addressable by the J
instruction according to this instruction's semantics.  The calculation
of the jump target is applied to the address of the delay-slot
instruction that immediately follows.  Adjust the check accordingly by
adding 4 to `e->code' that holds the address of the J instruction
itself.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8515/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:08 +01:00
Huacai Chen
7352c8b13d MIPS: Loongson: Set Loongson-3's ISA level to MIPS64R1
In CPU manual Loongson-3 is MIPS64R2 compatible, but during tests we
found that its EI/DI instructions have problems. So we just set the ISA
level to MIPS64R1.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/8320/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:07 +01:00
Huacai Chen
cc94ea3115 MIPS: Loongson: Fix the write-combine CCA value setting
All Loongson-2/3 processors support _CACHE_UNCACHED_ACCELERATED, not
only Loongson-3A.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/8319/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:07 +01:00
Manuel Lauss
842dfc11ea MIPS: Fix build with binutils 2.24.51+
Starting with version 2.24.51.20140728 MIPS binutils complain loudly
about mixing soft-float and hard-float object files, leading to this
build failure since GCC is invoked with "-msoft-float" on MIPS:

{standard input}: Warning: .gnu_attribute 4,3 requires `softfloat'
  LD      arch/mips/alchemy/common/built-in.o
mipsel-softfloat-linux-gnu-ld: Warning: arch/mips/alchemy/common/built-in.o
 uses -msoft-float (set by arch/mips/alchemy/common/prom.o),
 arch/mips/alchemy/common/sleeper.o uses -mhard-float

To fix this, we detect if GAS is new enough to support "-msoft-float" command
option, and if it does, we can let GCC pass it to GAS;  but then we also need
to sprinkle the files which make use of floating point registers with the
necessary ".set hardfloat" directives.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-07 15:07:36 +01:00
Zubair Lutfullah Kakakhel
30fa0530ff MIPS: CMA: Do not reserve memory if not required
Even if CMA is disabled, the for_each_memblock macro expands
to run reserve_bootmem once. Hence, reserve_bootmem attempts to
reserve location 0 of size 0.

Add a check to avoid that.

Issue was highlighted during testing with EVA enabled.
resrve_bootmem used to exit gracefully when passed arguments to
reserve 0 size location at 0 without EVA.

But with EVA enabled, macros would point to different addresses
and the code would trigger a BUG.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Tested-by: Markos Chandras <markos.chandras@imgtec.com>
Tested-by: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8231/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-29 02:59:25 +01:00
Ralf Baechle
5df4c8dbbc MIPS: Wire up bpf syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-27 03:37:42 +01:00
Markos Chandras
9d26024c96 MIPS: idle: Remove leftover __pastwait symbol and its references
The __pastwait symbol was only used by the address_is_in_r4k_wait_irqoff
function but this is no longer used since the SMTC removal in commit
b633648c5a ('MIPS: MT: Remove SMTC support'). That symbol also led to
build failures under certain random configuration due to the way the
compiler compiled the r4k_wait_irqoff function. If that function was
called multiple times, the __pastwait symbol was redefined breaking the
build like this:

CHK     include/generated/compile.h
CC      arch/mips/kernel/idle.o
{standard input}: Assembler messages:
{standard input}:527: Error: symbol `__pastwait' is already defined

Link: http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=1244879922.24479.30.camel%40falcon
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/7791/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-23 19:24:05 +02:00
Linus Torvalds
ab074ade9c Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
2014-10-19 16:25:56 -07:00
Linus Torvalds
857b50f5d0 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the MIPS pull request for the next kernel:

   - Zubair's patch series adds CMA support for MIPS.  Doing so it also
     touches ARM64 and x86.
   - remove the last instance of IRQF_DISABLED from arch/mips
   - updates to two of the MIPS defconfig files.
   - cleanup of how cache coherency bits are handled on MIPS and
     implement support for write-combining.
   - platform upgrades for Alchemy
   - move MIPS DTS files to arch/mips/boot/dts/"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (24 commits)
  MIPS: ralink: remove deprecated IRQF_DISABLED
  MIPS: pgtable.h: Implement the pgprot_writecombine function for MIPS
  MIPS: cpu-probe: Set the write-combine CCA value on per core basis
  MIPS: pgtable-bits: Define the CCA bit for WC writes on Ingenic cores
  MIPS: pgtable-bits: Move the CCA bits out of the core's ifdef blocks
  MIPS: DMA: Add cma support
  x86: use generic dma-contiguous.h
  arm64: use generic dma-contiguous.h
  asm-generic: Add dma-contiguous.h
  MIPS: BPF: Add new emit_long_instr macro
  MIPS: ralink: Move device-trees to arch/mips/boot/dts/
  MIPS: Netlogic: Move device-trees to arch/mips/boot/dts/
  MIPS: sead3: Move device-trees to arch/mips/boot/dts/
  MIPS: Lantiq: Move device-trees to arch/mips/boot/dts/
  MIPS: Octeon: Move device-trees to arch/mips/boot/dts/
  MIPS: Add support for building device-tree binaries
  MIPS: Create common infrastructure for building built-in device-trees
  MIPS: SEAD3: Enable DEVTMPFS
  MIPS: SEAD3: Regenerate defconfigs
  MIPS: Alchemy: DB1300: Add touch penirq support
  ...
2014-10-18 14:24:36 -07:00
Linus Torvalds
0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Linus Torvalds
ba1a96fc7d Merge branch 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 seccomp changes from Ingo Molnar:
 "This tree includes x86 seccomp filter speedups and related preparatory
  work, which touches core seccomp facilities as well.

  The main idea is to split seccomp into two phases, to be able to enter
  a simple fast path for syscalls with ptrace side effects.

  There's no substantial user-visible (and ABI) effects expected from
  this, except a change in how we emit a better audit record for
  SECCOMP_RET_TRACE events"

* 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86_64, entry: Use split-phase syscall_trace_enter for 64-bit syscalls
  x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls
  x86: Split syscall_trace_enter into two phases
  x86, entry: Only call user_exit if TIF_NOHZ
  x86, x32, audit: Fix x32's AUDIT_ARCH wrt audit
  seccomp: Document two-phase seccomp and arch-provided seccomp_data
  seccomp: Allow arch code to provide seccomp_data
  seccomp: Refactor the filter callback and the API
  seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing
2014-10-14 02:27:06 +02:00
Markos Chandras
8a574cfa26 MIPS: mcount: Adjust stack pointer for static trace in MIPS32
Every mcount() call in the MIPS 32-bit kernel is done as follows:

[...]
move at, ra
jal _mcount
addiu sp, sp, -8
[...]

but upon returning from the mcount() function, the stack pointer
is not adjusted properly. This is explained in details in 58b69401c7
(MIPS: Function tracer: Fix broken function tracing).

Commit ad8c396936 ("MIPS: Unbreak function tracer for 64-bit kernel.)
fixed the stack manipulation for 64-bit but it didn't fix it completely
for MIPS32.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7792/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-26 11:41:17 +02:00
Eric Paris
91397401bb ARCH: AUDIT: audit_syscall_entry() should not require the arch
We have a function where the arch can be queried, syscall_get_arch().
So rather than have every single piece of arch specific code use and/or
duplicate syscall_get_arch(), just have the audit code use the
syscall_get_arch() code.

Based-on-patch-by: Richard Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: linux-xtensa@linux-xtensa.org
Cc: x86@kernel.org
2014-09-23 16:21:26 -04:00
Markos Chandras
4f12b91d2d MIPS: cpu-probe: Set the write-combine CCA value on per core basis
Different cores use different CCA values to achieve write-combine
memory writes. For cores that do not support write-combine we
set the default value to CCA:2 (uncached, non-coherent) which is the
default value as set by the kernel.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7402/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22 13:35:53 +02:00
Zubair Lutfullah Kakakhel
f46493826a MIPS: DMA: Add cma support
Adds cma support to the MIPS architecture.

cma uses memblock. However, mips uses bootmem.
bootmem is informed about any regions reserved by memblock

dma api is modified to use cma reserved memory regions when available

Tested using cma_test. cma_test is a simple driver that assigns blocks
of memory from cma reserved sections.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: catalin.marinas@arm.com
Cc: will.deacon@arm.com
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: arnd@arndb.de
Cc: gregkh@linuxfoundation.org
Cc: m.szyprowski@samsung.com
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7360/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22 13:35:52 +02:00
Andy Lutomirski
a4412fc948 seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing
The secure_computing function took a syscall number parameter, but
it only paid any attention to that parameter if seccomp mode 1 was
enabled.  Rather than coming up with a kludge to get the parameter
to work in mode 2, just remove the parameter.

To avoid churn in arches that don't have seccomp filters (and may
not even support syscall_get_nr right now), this leaves the
parameter in secure_computing_strict, which is now a real function.

For ARM, this is a bit ugly due to the fact that ARM conditionally
supports seccomp filters.  Fixing that would probably only be a
couple of lines of code, but it should be coordinated with the audit
maintainers.

This will be a slight slowdown on some arches.  The right fix is to
pass in all of seccomp_data instead of trying to make just the
syscall nr part be fast.

This is a prerequisite for making two-phase seccomp work cleanly.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: x86@kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
2014-09-03 14:58:17 -07:00
Christoph Lameter
35898716b4 mips: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:51 -04:00
Ralf Baechle
42944521af MIPS: Wire up new syscalls getrandom and memfd_create.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-26 03:03:40 +02:00
Markos Chandras
56d2960958 MIPS: CPS: Initialize EVA before bringing up VPEs from secondary cores
The CPS code is doing several memory loads when configuring the VPEs
from secondary cores, so the segmentation control registers must be
initialized in time otherwise the kernel will crash with strange
TLB exceptions.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7424/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-26 02:18:57 +02:00
Markos Chandras
ad61ba23f1 MIPS: scall64-o32: Fix indirect syscall detection
Commit 4c21b8fd8f (MIPS: seccomp: Handle indirect system calls (o32))
added indirect syscall detection for O32 processes running on MIPS64
but it did not work as expected. The reason is the the scall64-o32
implementation differs compared to scall32-o32. In the former, the v0
(syscall number) register contains the absolute syscall number
(4000 + X) whereas in the latter it contains the relative syscall
number (X). Fix the code to avoid doing an extra addition, and load
the v0 register directly to the first argument for syscall_trace_enter.
Moreover, set the .reorder assembler option in order to have better
control on this part of the assembly code.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7481/
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-26 02:18:56 +02:00
Yang Wei
014365f583 MIPS: perf: Mark pmu interupt IRQF_NO_THREAD
In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded

in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0

[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-26 02:18:51 +02:00
Yang Wei
91ffaa2783 MIPS: kdump: Set correct value to kexec_indirection_page variable
Since there is not indirection page in crash type, so the vaule of the head
field of kimage structure is not equal to the address of indirection page but
IND_DONE. so we have to set kexec_indirection_page variable to the address of
the head field of image structure.

[ralf@linux-mips.org: Don't add pointless empty line, fix trailing
whitespace damage.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7499/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-25 16:33:44 +02:00
Markos Chandras
6521d9a436 MIPS: CPS: Initialize EVA before bringing up VPEs from secondary cores
The CPS code is doing several memory loads when configuring the VPEs
from secondary cores, so the segmentation control registers must be
initialized in time otherwise the kernel will crash with strange
TLB exceptions.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7424/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-19 18:24:41 +02:00
Markos Chandras
5245689900 MIPS: scall64-o32: Fix indirect syscall detection
Commit 4c21b8fd8f (MIPS: seccomp: Handle indirect system calls (o32))
added indirect syscall detection for O32 processes running on MIPS64
but it did not work as expected. The reason is the the scall64-o32
implementation differs compared to scall32-o32. In the former, the v0
(syscall number) register contains the absolute syscall number
(4000 + X) whereas in the latter it contains the relative syscall
number (X). Fix the code to avoid doing an extra addition, and load
the v0 register directly to the first argument for syscall_trace_enter.
Moreover, set the .reorder assembler option in order to have better
control on this part of the assembly code.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7481/
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-19 18:24:40 +02:00
Yang Wei
ec756d45b7 MIPS: perf: Mark pmu interupt IRQF_NO_THREAD
In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded

in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0

[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-18 22:14:39 +02:00
Linus Torvalds
63b12bdb0d Merge branch 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc
Pull arch signal handling cleanup from Richard Weinberger:
 "This patch series moves all remaining archs to the get_signal(),
  signal_setup_done() and sigsp() functions.

  Currently these archs use open coded variants of the said functions.
  Further, unused parameters get removed from get_signal_to_deliver(),
  tracehook_signal_handler() and signal_delivered().

  At the end of the day we save around 500 lines of code."

* 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (43 commits)
  powerpc: Use sigsp()
  openrisc: Use sigsp()
  mn10300: Use sigsp()
  mips: Use sigsp()
  microblaze: Use sigsp()
  metag: Use sigsp()
  m68k: Use sigsp()
  m32r: Use sigsp()
  hexagon: Use sigsp()
  frv: Use sigsp()
  cris: Use sigsp()
  c6x: Use sigsp()
  blackfin: Use sigsp()
  avr32: Use sigsp()
  arm64: Use sigsp()
  arc: Use sigsp()
  sas_ss_flags: Remove nested ternary if
  Rip out get_signal_to_deliver()
  Clean up signal_delivered()
  tracehook_signal_handler: Remove sig, info, ka and regs
  ...
2014-08-09 09:58:12 -07:00
Linus Torvalds
e669830526 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for 3.17.  It contains:

   - misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy  updates
   - MIPS ptrace updates and cleanups
   - various fixes that will also go to -stable
   - a number of cleanups and small non-critical fixes.
   - NUMA support for the Loongson 3.
   - more support for MSA
   - support for MAAR
   - various FP enhancements and fixes"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
  MIPS: jz4740: remove unnecessary null test before debugfs_remove
  MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive
  MIPS: ZBOOT: implement stack protector in compressed boot phase
  MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT
  MIPS: Bonito64: remove a duplicate define
  MIPS: Malta: initialise MAARs
  MIPS: Initialise MAARs
  MIPS: detect presence of MAARs
  MIPS: define MAAR register accessors & bits
  MIPS: mark MSA experimental
  MIPS: Don't build MSA support unless it can be used
  MIPS: consistently clear MSA flags when starting & copying threads
  MIPS: 16 byte align MSA vector context
  MIPS: disable preemption whilst initialising MSA
  MIPS: ensure MSA gets disabled during boot
  MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains
  MIPS: fix MSA context for tasks which don't use FP first
  MIPS: init upper 64b of vector registers when MSA is first used
  MIPS: save/disable MSA in lose_fpu
  MIPS: preserve scalar FP CSR when switching vector context
  ...
2014-08-07 08:47:00 -07:00
Linus Torvalds
bb2cbf5e93 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "In this release:

   - PKCS#7 parser for the key management subsystem from David Howells
   - appoint Kees Cook as seccomp maintainer
   - bugfixes and general maintenance across the subsystem"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (94 commits)
  X.509: Need to export x509_request_asymmetric_key()
  netlabel: shorter names for the NetLabel catmap funcs/structs
  netlabel: fix the catmap walking functions
  netlabel: fix the horribly broken catmap functions
  netlabel: fix a problem when setting bits below the previously lowest bit
  PKCS#7: X.509 certificate issuer and subject are mandatory fields in the ASN.1
  tpm: simplify code by using %*phN specifier
  tpm: Provide a generic means to override the chip returned timeouts
  tpm: missing tpm_chip_put in tpm_get_random()
  tpm: Properly clean sysfs entries in error path
  tpm: Add missing tpm_do_selftest to ST33 I2C driver
  PKCS#7: Use x509_request_asymmetric_key()
  Revert "selinux: fix the default socket labeling in sock_graft()"
  X.509: x509_request_asymmetric_keys() doesn't need string length arguments
  PKCS#7: fix sparse non static symbol warning
  KEYS: revert encrypted key change
  ima: add support for measuring and appraising firmware
  firmware_class: perform new LSM checks
  security: introduce kernel_fw_from_file hook
  PKCS#7: Missing inclusion of linux/err.h
  ...
2014-08-06 08:06:39 -07:00
Richard Weinberger
7c4f563507 mips: Use sigsp()
Use sigsp() instead of the open coded variant.

Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06 13:04:30 +02:00
Richard Weinberger
81d103bf80 mips: Use get_signal() signal_setup_done()
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06 13:03:08 +02:00
Ralf Baechle
475d5928b7 Merge branch '3.16-fixes' into mips-for-linux-next 2014-08-02 00:07:03 +02:00
Paul Burton
1f6c52ff72 MIPS: detect presence of MAARs
Detect the presence of MAAR using the MRP bit in Config5, and record
that presence using a CPU option bit. A cpu_has_maar macro will then
allow code to conditionalise upon the presence of MAARs.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7330/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:45 +02:00
Paul Burton
7daef8f261 MIPS: consistently clear MSA flags when starting & copying threads
The TIF_MSA_CTX_LIVE flag (indicating that a task has MSA context which
needs to be preserved) was being cleared in start_thread, but the
TIF_USEDMSA flag (indicating that a task has used MSA in this timeslice)
was not. In copy_thread neither flag was cleared, but both need to be.
Without clearing these flags the kernel will proceed to attempt to save
MSA context when the task is context switched out, and if the task had
not used MSA in the meantime then it will fail because MSA or the FPU
are disabled. The end result is typically:

  do_cpu invoked from kernel context![#1]:
  CPU: 0 PID: 99 Comm: sh Not tainted 3.16.0-rc4-00025-g6dc9476-dirty #88
  task: 8f23dc60 ti: 8f1d8000 task.ti: 8f1d8000
  ...
  Call Trace:
  [<8010edbc>] resume+0x5c/0x280
  [<80481e0c>] __schedule+0x370/0x800
  [<80104838>] work_resched+0x8/0x2c

Fix by consistently clearing both flags in both functions.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7309/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:45 +02:00
Paul Burton
762a1f4388 MIPS: disable preemption whilst initialising MSA
Preemption must be disabled throughout the process of enabling the FPU,
enabling MSA & initialising the vector registers. Without doing so it
is possible to lose the FPU or MSA whilst initialising them causing
that initialisation to fail.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7307/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton
3587ea888b MIPS: ensure MSA gets disabled during boot
The kernel relies upon MSA being disabled when a task begins running,
so that it can initialise or restore context in response to the
resulting MSA disabled exception. Previously the state of MSA following
boot was left as it was before the kernel ran, where MSA could
potentially have been enabled. Explicitly disable it during boot to
prevent any problems.

As a nice side effect the code reads a little better too.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7306/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton
732c0c3c70 MIPS: fix MSA context for tasks which don't use FP first
If a task does not execute scalar FP instructions prior to using MSA
then the flags indicating that the task has live MSA context were not
being set. The upper 64b of each vector register would then be lost
upon the tasks first context switch after using MSA.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7500/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton
c9017757c5 MIPS: init upper 64b of vector registers when MSA is first used
When a task first makes use of MSA we need to ensure that the upper
64b of the vector registers are set to some value such that no
information can be leaked to it from the previous task to use MSA
context on the CPU. The architecture formerly specified that these
bits would be cleared to 0 when a scalar FP instructions wrote to the
aliased FP registers, which would have implicitly handled this as the
kernel restored scalar FP context. However more recent versions of the
specification now state that the value of the bits in such cases is
unpredictable. Initialise them explictly to be sure, and set all the
bits to 1 rather than 0 for consistency with the least significant
64b.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7497/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton
b83406735a MIPS: preserve scalar FP CSR when switching vector context
Switching the vector context implicitly saves & restores the state of
the aliased scalar FP data registers, however the scalar FP control
& status register is distinct from the MSA control & status register.
In order to allow scalar FP to function correctly in programs using
MSA, the scalar CSR needs to be saved & restored along with the MSA
vector context.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7301/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:43 +02:00
Paul Burton
f7a46fa7bb MIPS: save/restore MSACSR register on context switch
I added a field for the MSACSR register in struct mips_fpu_struct, but
never actually made use of it... This is a clear bug. Save and restore
the MSACSR register along with the vector registers.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7300/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:43 +02:00