arch/idle: Change arch_cpu_idle() behavior: always exit with IRQs disabled

Current arch_cpu_idle() is called with IRQs disabled, but will return
with IRQs enabled.

However, the very first thing the

arch/idle: Change arch_cpu_idle() behavior: always exit with IRQs disabled

Current arch_cpu_idle() is called with IRQs disabled, but will return
with IRQs enabled.

However, the very first thing the generic code does after calling
arch_cpu_idle() is raw_local_irq_disable(). This means that
architectures that can idle with IRQs disabled end up doing a
pointless 'enable-disable' dance.

Therefore, push this IRQ disabling into the idle function, meaning
that those architectures can avoid the pointless IRQ state flipping.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Tested-by: Tony Lindgren <[email protected]>
Tested-by: Ulf Hansson <[email protected]>
Reviewed-by: Gautham R. Shenoy <[email protected]>
Acked-by: Mark Rutland <[email protected]> [arm64]
Acked-by: Rafael J. Wysocki <[email protected]>
Acked-by: Guo Ren <[email protected]>
Acked-by: Frederic Weisbecker <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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[elf][non-regset] uninline elf_core_copy_task_fpregs() (and lose pt_regs argument)

Don't bother with pointless macros - we are not sharing it with aout coredumps
anymore. Just convert the underlyin

[elf][non-regset] uninline elf_core_copy_task_fpregs() (and lose pt_regs argument)

Don't bother with pointless macros - we are not sharing it with aout coredumps
anymore. Just convert the underlying functions to the same arguments (nobody
uses regs, actually) and call them elf_core_copy_task_fpregs(). And unexport
the entire bunch, while we are at it.

[added missing includes in arch/{csky,m68k,um}/kernel/process.c to avoid extra
warnings about the lack of externs getting added to huge piles for those
files. Pointless, but...]

Signed-off-by: Al Viro <[email protected]>

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fork: Generalize PF_IO_WORKER handling

Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any ta

fork: Generalize PF_IO_WORKER handling

Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.

The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.

The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size". These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: "Eric W. Biederman" <[email protected]>

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fork: Pass struct kernel_clone_args into copy_thread

With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.

The kernel

fork: Pass struct kernel_clone_args into copy_thread

With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.

The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.

Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.

v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: "Eric W. Biederman" <[email protected]>

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uaccess: remove CONFIG_SET_FS

There are no remaining callers of set_fs(), so CONFIG_SET_FS
can be removed globally, along with the thread_info field and
any references to it.

This turns access_ok()

uaccess: remove CONFIG_SET_FS

There are no remaining callers of set_fs(), so CONFIG_SET_FS
can be removed globally, along with the thread_info field and
any references to it.

This turns access_ok() into a cheaper check against TASK_SIZE_MAX.

As CONFIG_SET_FS is now gone, drop all remaining references to
set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel().

Acked-by: Sam Ravnborg <[email protected]> # for sparc32 changes
Acked-by: "Eric W. Biederman" <[email protected]>
Tested-by: Sergey Matyukevich <[email protected]> # for arc changes
Acked-by: Stafford Horne <[email protected]> # [openrisc, asm-generic]
Acked-by: Dinh Nguyen <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

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sched: Add wrapper for get_wchan() to keep task blocked

Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.

Suggested-by: Peter Zij

sched: Add wrapper for get_wchan() to keep task blocked

Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.

Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Acked-by: Russell King (Oracle) <[email protected]> [arm]
Tested-by: Mark Rutland <[email protected]> [arm64]
Link: https://lkml.kernel.org/r/[email protected]

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arch: setup PF_IO_WORKER threads like PF_KTHREAD

PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure

arch: setup PF_IO_WORKER threads like PF_KTHREAD

PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure that every arch sets up the PF_IO_WORKER threads like kthreads
in the arch implementation of copy_thread().

Signed-off-by: Jens Axboe <[email protected]>

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microblaze: Remove noMMU code

This configuration is obsolete and likely none is really using it. That's
why remove it to simplify code.

Note about CONFIG_MMU in hw_exception_handler.S is left inten

microblaze: Remove noMMU code

This configuration is obsolete and likely none is really using it. That's
why remove it to simplify code.

Note about CONFIG_MMU in hw_exception_handler.S is left intentionally
for better comment understanding.

Cc: Mike Rapoport <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Signed-off-by: Michal Simek <[email protected]>
Acked-by: Mike Rapoport <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Link: https://lore.kernel.org/r/43486cab370e0c0a79860120b71e0caac75a7e44.1606397528.git.michal.simek@xilinx.com

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sched/idle: Fix arch_cpu_idle() vs tracing

We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.

Switch all arch_cpu_idle() i

sched/idle: Fix arch_cpu_idle() vs tracing

We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.

Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.

(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)

Reported-by: Sven Schnelle <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Mark Rutland <[email protected]>
Tested-by: Mark Rutland <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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mm: remove unneeded includes of <asm/pgalloc.h>

Patch series "mm: cleanup usage of <asm/pgalloc.h>"

Most architectures have very similar versions of pXd_alloc_one() and
pXd_free_one() for intermedi

mm: remove unneeded includes of <asm/pgalloc.h>

Patch series "mm: cleanup usage of <asm/pgalloc.h>"

Most architectures have very similar versions of pXd_alloc_one() and
pXd_free_one() for intermediate levels of page table. These patches add
generic versions of these functions in <asm-generic/pgalloc.h> and enable
use of the generic functions where appropriate.

In addition, functions declared and defined in <asm/pgalloc.h> headers are
used mostly by core mm and early mm initialization in arch and there is no
actual reason to have the <asm/pgalloc.h> included all over the place.
The first patch in this series removes unneeded includes of
<asm/pgalloc.h>

In the end it didn't work out as neatly as I hoped and moving
pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require
unnecessary changes to arches that have custom page table allocations, so
I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local
to mm/.

This patch (of 8):

In most cases <asm/pgalloc.h> header is required only for allocations of
page table memory. Most of the .c files that include that header do not
use symbols declared in <asm/pgalloc.h> and do not require that header.

As for the other header files that used to include <asm/pgalloc.h>, it is
possible to move that include into the .c file that actually uses symbols
from <asm/pgalloc.h> and drop the include from the header file.

The process was somewhat automated using

sed -i -E '/[<"]asm\/pgalloc\.h/d' \
$(grep -L -w -f /tmp/xx \
$(git grep -E -l '[<"]asm/pgalloc\.h'))

where /tmp/xx contains all the symbols defined in
arch/*/include/asm/pgalloc.h.

[[email protected]: fix powerpc warning]

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Pekka Enberg <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Cc: Abdul Haleem <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Satheesh Rajendran <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

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arch: rename copy_thread_tls() back to copy_thread()

Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that o

arch: rename copy_thread_tls() back to copy_thread()

Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().

Cc: [email protected]
Acked-by: Thomas Bogendoerfer <[email protected]>A
Acked-by: Stafford Horne <[email protected]>
Acked-by: Greentime Hu <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>A
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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microblaze: switch to copy_thread_tls()

Use the copy_thread_tls() calling convention which passes tls through a
register. This is required so we can remove the copy_thread{_tls}() split
and remove t

microblaze: switch to copy_thread_tls()

Use the copy_thread_tls() calling convention which passes tls through a
register. This is required so we can remove the copy_thread{_tls}() split
and remove the HAVE_COPY_THREAD_TLS macro.

Cc: Michal Simek <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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arch: remove unused macro/function thread_saved_pc()

The only user of thread_saved_pc() in non-arch-specific code was removed
in commit 8243d5597793 ("sched/core: Remove pointless printout in
sched_

arch: remove unused macro/function thread_saved_pc()

The only user of thread_saved_pc() in non-arch-specific code was removed
in commit 8243d5597793 ("sched/core: Remove pointless printout in
sched_show_task()"). Remove the implementations as well.

Some architectures use thread_saved_pc() in their arch-specific code.
Leave their thread_saved_pc() intact.

Signed-off-by: Tobias Klauser <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be pic

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up fro

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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microblaze: Fix sparse warning because of missing cpu.h header

Warning:
arch/microblaze/kernel/process.c:164:6: warning: symbol 'arch_cpu_idle'
was not declared. Should it be static?

Signed-off-by:

microblaze: Fix sparse warning because of missing cpu.h header

Warning:
arch/microblaze/kernel/process.c:164:6: warning: symbol 'arch_cpu_idle'
was not declared. Should it be static?

Signed-off-by: Michal Simek <[email protected]>

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microblaze: Enable IRQ in arch_cpu_idle

Microblaze requires to enable IRQ in cpu_idle loop.

It should be the part of this patch:
"microblaze: Use generic idle loop"
(sha1: e962bb9e9cf73b8c8893c9590

microblaze: Enable IRQ in arch_cpu_idle

Microblaze requires to enable IRQ in cpu_idle loop.

It should be the part of this patch:
"microblaze: Use generic idle loop"
(sha1: e962bb9e9cf73b8c8893c95903e791dd5ec19fb4)

Signed-off-by: Michal Simek <[email protected]>

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dump_stack: unify debug information printed by show_regs()

show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slig

dump_stack: unify debug information printed by show_regs()

show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms. This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.

show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.

* Archs which didn't print debug info now do.

alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
um, xtensa

* Already prints debug info. Replaced with show_regs_print_info().
The printed information is superset of what used to be there.

arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86

* s390 is special in that it used to print arch-specific information
along with generic debug info. Heiko and Martin think that the
arch-specific extra isn't worth keeping s390 specfic implementation.
Converted to use the generic version.

Note that now all archs print the debug info before actual register
dumps.

An example BUG() dump follows.

kernel BUG at /work/os/work/kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[<ffffffff81000312>] do_one_initcall+0x122/0x170
[<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
[<ffffffff81c47760>] ? rest_init+0x140/0x140
[<ffffffff81c4776e>] kernel_init+0xe/0xf0
[<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
[<ffffffff81c47760>] ? rest_init+0x140/0x140
...

v2: Typo fix in x86-32.

v3: CPU number dropped from show_regs_print_info() as
dump_stack_print_info() has been updated to print it. s390
specific implementation dropped as requested by s390 maintainers.

Signed-off-by: Tejun Heo <[email protected]>
Acked-by: David S. Miller <[email protected]>
Acked-by: Jesper Nilsson <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Fengguang Wu <[email protected]>
Cc: Mike Frysinger <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Acked-by: Chris Metcalf <[email protected]> [tile bits]
Acked-by: Richard Kuo <[email protected]> [hexagon bits]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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microblaze: Use generic idle loop

The microblaze idle loop provides a polling and a non polling version,
which are suprisingly both polling, just with slightly different
instrumentation. Remove them

microblaze: Use generic idle loop

The microblaze idle loop provides a polling and a non polling version,
which are suprisingly both polling, just with slightly different
instrumentation. Remove them and use the generic poller.

Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Paul McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Reviewed-by: Cc: Srivatsa S. Bhat <[email protected]>
Cc: Magnus Damm <[email protected]>
Cc: Michal Simek <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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arch: Cleanup enable/disable_hlt

enable/disable_hlt() does not need to be exported and can be killed on
architectures which do not use it at all.

Signed-off-by: Thomas Gleixner <[email protected]>

arch: Cleanup enable/disable_hlt

enable/disable_hlt() does not need to be exported and can be killed on
architectures which do not use it at all.

Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Paul McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Reviewed-by: Cc: Srivatsa S. Bhat <[email protected]>
Cc: Magnus Damm <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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microblaze idle: Fix compile error

Commit def8203 ("microblaze idle: delete pm_idle") introduced the following
compile error:

arch/microblaze/kernel/process.c: In function 'cpu_idle':
arch/microb

microblaze idle: Fix compile error

Commit def8203 ("microblaze idle: delete pm_idle") introduced the following
compile error:

arch/microblaze/kernel/process.c: In function 'cpu_idle':
arch/microblaze/kernel/process.c:100: error: 'idle' undeclared (first use in this function)
arch/microblaze/kernel/process.c:100: error: (Each undeclared identifier is reported only once
arch/microblaze/kernel/process.c:100: error: for each function it appears in.)
arch/microblaze/kernel/process.c:106: error: implicit declaration of function 'idle'

This patch fixes it.

Signed-off-by: Lars-Peter Clausen <[email protected]>
Acked-by: Len Brown <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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microblaze idle: delete pm_idle

pm_idle on microblaze served no purpose.

Signed-off-by: Len Brown <[email protected]>
Cc: [email protected]

microblaze: Do not use module.h in files which are not modules

Based on the patch:
"lib: reduce the use of module.h wherever possible"
(sha1: 8bc3bcc93a2b4e47d5d410146f6546bca6171663)
fix all microb

microblaze: Do not use module.h in files which are not modules

Based on the patch:
"lib: reduce the use of module.h wherever possible"
(sha1: 8bc3bcc93a2b4e47d5d410146f6546bca6171663)
fix all microblaze files which are not modules.

Signed-off-by: Michal Simek <[email protected]>

show more ...

microblaze: Fix coding style issues

Fix coding style issues reported by checkpatch.pl.

Signed-off-by: Michal Simek <[email protected]>