Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRichard Weinberger <richard@nod.at>

Without this, a 'break' instruction is executed very early in the boot and
the boot hangs.

The problem is that clang doesn't honour named registers on local variables
and silently treats them as normal uninitialized variables. However, it
does honour them on global variables.
Signed-off-by: NDaniel Sanders <daniel.sanders@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: David Daney <ddaney.cavm@gmail.com>
Acked-by: NBehan Webster <behanw@converseincode.com>
Patchwork: https://patchwork.linux-mips.org/patch/9311/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: NRichard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Register 2 is alredy overwritten by the return value when
syscall_trace_leave() is called.
Signed-off-by: NLars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9187/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Hybrid FPRs is a scheme where scalar FP registers are 64b wide, but
accesses to odd indexed single registers use bits 63:32 of the
preceeding even indexed 64b register. In this mode all FP code
except that built for the plain FP64 ABI can execute correctly. Most
notably a combination of FP64A & FP32 code can execute correctly,
allowing for existing FP32 binaries to be linked with new FP64A binaries
that can make use of 64 bit FP & MSA.

Hybrid FPRs are implemented by setting both the FR & FRE bits, trapping
& emulating single precision FP instructions (via Reserved Instruction
exceptions) whilst allowing others to execute natively. It therefore has
a penalty in terms of execution speed, and should only be used when no
fully native mode can be. As more binaries are recompiled to use either
the FPXX or FP64(A) ABIs, the need for hybrid FPRs should diminish.
However in the short to mid term it allows for a gradual transition
towards that world, rather than a complete ABI break which is not
feasible for some users & not desirable for many.

A task will be executed using the hybrid FPR scheme when its
TIF_HYBRID_FPREGS flag is set & TIF_32BIT_FPREGS is clear. A further
patch will set the flags as necessary, this patch simply adds the
infrastructure necessary for the hybrid FPR mode to work.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7683/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch adds support for context switching the MSA vector registers.
These 128 bit vector registers are aliased with the FP registers - an
FP register accesses the least significant bits of the vector register
with which it is aliased (ie. the register with the same index). Due to
both this & the requirement that the scalar FPU must be 64-bit (FR=1) if
enabled at the same time as MSA the kernel will enable MSA & scalar FP
at the same time for tasks which use MSA. If we restore the MSA vector
context then we might as well enable the scalar FPU since the reason it
was left disabled was to allow for lazy FP context restoring - but we
just restored the FP context as it's a subset of the vector context. If
we restore the FP context and have previously used MSA then we have to
restore the whole vector context anyway (see comment in
enable_restore_fp_context for details) so similarly we might as well
enable MSA.

Thus if a task does not use MSA then it will continue to behave as
without this patch - the scalar FP context will be saved & restored as
usual. But if a task executes an MSA instruction then it will save &
restore the vector context forever more.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6431/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add _TIF_SECCOMP flag to _TIF_WORK_SYSCALL_ENTRY to indicate
that the system call needs to be checked against a seccomp filter.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Reviewed-by: NPaul Burton <paul.burton@imgtec.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6405/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

CPUs implementing MIPS32 R2 may include a 64-bit FPU, just as MIPS64 CPUs
do. In order to preserve backwards compatibility a 64-bit FPU will act
like a 32-bit FPU (by accessing doubles from the least significant 32
bits of an even-odd pair of FP registers) when the Status.FR bit is
zero, again just like a mips64 CPU. The standard O32 ABI is defined
expecting a 32-bit FPU, however recent toolchains support use of a
64-bit FPU from an O32 MIPS32 executable. When an ELF executable is
built to use a 64-bit FPU a new flag (EF_MIPS_FP64) is set in the ELF
header.

With this patch the kernel will check the EF_MIPS_FP64 flag when
executing an O32 binary, and set Status.FR accordingly. The addition
of O32 64-bit FP support lessens the opportunity for optimisation in
the FPU emulator, so a CONFIG_MIPS_O32_FP64_SUPPORT Kconfig option is
introduced to allow this support to be disabled for those that don't
require it.

Inspired by an earlier patch by Leonid Yegoshin, but implemented more
cleanly & correctly.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/6154/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

No point in having this bit defined by architecture.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The definition of the CP0 register used to save the smp processor
id is repicated in many files, move them all to thread_info.h.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5708/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This enables support for CONFIG_NO_HZ_FULL.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This will simplify further modifications.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

With LTE this fixes this issue:

  LDFINAL vmlinux.o
arch/mips/built-in.o (symbol from plugin): In function `sgimc_init':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
kernel/built-in.o (symbol from plugin): In function `get_task_mm':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
mm/built-in.o (symbol from plugin): In function `iov_iter_single_seg_count':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
fs/built-in.o (symbol from plugin): In function `finish_no_open':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
ipc/built-in.o (symbol from plugin): In function `ipc_init_ids':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
security/built-in.o (symbol from plugin): In function `key_schedule_gc':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
crypto/built-in.o (symbol from plugin): In function `crypto_find_alg':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
block/built-in.o (symbol from plugin): In function `elv_rb_find':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
argv_split.o (symbol from plugin): In function `argv_free':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
dec_and_lock.o (symbol from plugin): In function `_atomic_dec_and_lock':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
extable.o (symbol from plugin): In function `sort_extable':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
flex_proportions.o (symbol from plugin): In function `fprop_global_init':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
idr.o (symbol from plugin): In function `idr_for_each':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
is_single_threaded.o (symbol from plugin): In function `current_is_single_threaded':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
kobject.o (symbol from plugin): In function `kobject_get':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
kobject_uevent.o (symbol from plugin): In function `add_uevent_var':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
plist.o (symbol from plugin): In function `plist_add':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
radix-tree.o (symbol from plugin): In function `radix_tree_lookup_slot':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
ratelimit.o (symbol from plugin): In function `___ratelimit':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
rwsem-spinlock.o (symbol from plugin): In function `__init_rwsem':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
show_mem.o (symbol from plugin): In function `show_mem':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
timerqueue.o (symbol from plugin): In function `timerqueue_iterate_next':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
vsprintf.o (symbol from plugin): In function `simple_strtoull':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
delay.o (symbol from plugin): In function `__delay':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
mips-atomic.o (symbol from plugin): In function `arch_local_irq_disable':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
uncached.o (symbol from plugin): In function `run_uncached':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
lib/built-in.o (symbol from plugin): In function `_bcd2bin':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
arch/mips/lib/built-in.o (symbol from plugin): In function `ioread8':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
drivers/built-in.o (symbol from plugin): In function `fb_notifier_call_chain':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
net/built-in.o (symbol from plugin): In function `sock_from_file':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here
klist.o (symbol from plugin): In function `klist_init':
(.text+0x0): multiple definition of `$28'
init/built-in.o (symbol from plugin):(.text+0x0): first defined here

It also makes the code a little more readable, so let's merge it.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The value is incorrect and were copied in Linux 2.5.4 from i386.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make default just return 0.  The current default (checking
TIF_POLLING_NRFLAG) is taken to architectures that need it;
ones that don't do polling in their idle threads don't need
to defined TIF_POLLING_NRFLAG at all.

ia64 defined both TS_POLLING (used by its tsk_is_polling())
and TIF_POLLING_NRFLAG (not used at all).  Killed the latter...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

never used...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

If it's set, SIGPENDING is also set.  And SIGPENDING is present in
the masks...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

If it's set, SIGPENDING is also set.  And SIGPENDING is present in
the masks...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

Improper alignment can lead to unbootable systems and/or random
crashes.

[ralf@linux-mips.org: This is a lond standing bug since
6eb10bc9 (kernel.org) rsp.
c422a10917f75fd19fa7fe070aaaa23e384dae6f (lmo) [MIPS: Clean up linker script
using new linker script macros.] so dates back to 2.6.32.]
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/3881/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

No point in using kmalloc for allocating 0, 1 resp. 2 pages for
threadinfo.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20120505150141.936950979@linutronix.de

Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arch@vger.kernel.org

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add a node parameter to alloc_thread_info(), and change its name to
alloc_thread_info_node()

This change is needed to allow NUMA aware kthread_create_on_cpu()
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add stackoverflow detection to mips arch
Signed-off-by: NAdam Jiang <jiang.adam@gmail.com>
Cc: dmitri.vorobiev@movial.com
Cc: wuzhangjin@gmail.com
Cc: ddaney@caviumnetworks.com
Cc: peterz@infradead.org
Cc: fweisbec@gmail.com
Cc: tj@kernel.org
Cc: tglx@linutronix.de
Cc: mingo@elte.hu
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1559/
Patchwork: https://patchwork.linux-mips.org/patch/1651/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

_TIF_WORK_MASK false had _TIF_SYSCALL_AUDIT set.  If a thread's
_TIF_SYSCALL_AUDIT is ever set this will lead to an endless loop on the
way out from a syscall.

Currently this is only a theoretic bug as init/Kconfig doesn't allow
AUDIT_SYSCALL to be enabled for MIPS.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NAndreas Dilger <adilger@dilger.ca>
Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet
available, and, whilst we're at it, have it call the appropriate tracehook.

After this patch, blackfin, m68k* and xtensa still lack support and need
alteration of assembly code to make it work.

Resume notification can then be used (by a later patch) to install a new
session keyring on the parent of a process.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>

cc: linux-arch@vger.kernel.org
Signed-off-by: NJames Morris <jmorris@namei.org>

Pull the initial preempt_count value into a single
definition site.

Maintainers for: alpha, ia64 and m68k, please have a look,
your arch code is funny.

The header magic is a bit odd, but similar to the KERNEL_DS
one, CPP waits with expanding these macros until the
INIT_THREAD_INFO macro itself is expanded, which is in
arch/*/kernel/init_task.c where we've already included
sched.h so we're good.

Cc: tony.luck@intel.com
Cc: rth@twiddle.net
Cc: geert@linux-m68k.org
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Beyond the requirements of the architecture standard Cavium also supports
8k and 32k pages.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Acked-by: NDavid Daney <ddaney@caviumnetworks.com>

Signed-off-by: NZhang Le <r0bertz@gentoo.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>