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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csky: Fix versioncheck warnings

$make versioncheck

arch/csky/include/asm/io.h: 8 linux/version.h not needed.
arch/csky/kernel/process.c: 5 linux/version.h not needed.
arch/csky/mm/dma-mapping.c: 12

csky: Fix versioncheck warnings

$make versioncheck

arch/csky/include/asm/io.h: 8 linux/version.h not needed.
arch/csky/kernel/process.c: 5 linux/version.h not needed.
arch/csky/mm/dma-mapping.c: 12 linux/version.h not needed.

comments from Randy:

The patch makes sense but these are not compile warnings.
They come from scripts/checkversion.pl, which can be called
by 'make versioncheck', so I suppose that something in your
build system is running 'make versioncheck'.

Signed-off-by: Deyan Wang <[email protected]>
Acked-by: Randy Dunlap <[email protected]>
Signed-off-by: Guo Ren <[email protected]>
Signed-off-by: Guo Ren <[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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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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csky: remove unusued thread_saved_pc and *_segments functions/macros

These are used nowhere in the tree (except for some architectures which
define them for their own use) and were already removed f

csky: remove unusued thread_saved_pc and *_segments functions/macros

These are used nowhere in the tree (except for some architectures which
define them for their own use) and were already removed for other
architectures in:

commit 6474924e2b5d ("arch: remove unused macro/function thread_saved_pc()")
commit c17c02040bf0 ("arch: remove unused *_segments() macros/functions")

Remove them from arch/csky as well.

Signed-off-by: Tobias Klauser <[email protected]>
Signed-off-by: Guo Ren <[email protected]>
Cc: Arnd Bergmann <[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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csky: Fixup gdbmacros.txt with name sp in thread_struct

The gdbmacros.txt use sp in thread_struct, but csky use ksp. This
cause bttnobp fail to excute.

TODO:
- Still couldn't display the contents

csky: Fixup gdbmacros.txt with name sp in thread_struct

The gdbmacros.txt use sp in thread_struct, but csky use ksp. This
cause bttnobp fail to excute.

TODO:
- Still couldn't display the contents of stack.

Signed-off-by: Guo Ren <[email protected]>

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csky: Fixup calltrace panic

The implementation of show_stack will panic with wrong fp:

addr = *fp++;

because the fp isn't checked properly.

The current implementations of show_stack, wchan and

csky: Fixup calltrace panic

The implementation of show_stack will panic with wrong fp:

addr = *fp++;

because the fp isn't checked properly.

The current implementations of show_stack, wchan and stack_trace
haven't been designed properly, so just deprecate them.

This patch is a reference to riscv's way, all codes are modified from
arm's. The patch is passed with:

- cat /proc/<pid>/stack
- cat /proc/<pid>/wchan
- echo c > /proc/sysrq-trigger

Signed-off-by: Guo Ren <[email protected]>

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csky: Implement copy_thread_tls

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Cc: Amanieu d'Antras <[email protected]>
Signed-off-by: Guo Ren <guor

csky: Implement copy_thread_tls

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Cc: Amanieu d'Antras <[email protected]>
Signed-off-by: Guo Ren <[email protected]>

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csky: Initial stack protector support

This is a basic -fstack-protector support without per-task canary
switching. The protector will report something like when stack
corruption is detected:

It's t

csky: Initial stack protector support

This is a basic -fstack-protector support without per-task canary
switching. The protector will report something like when stack
corruption is detected:

It's tested with strcpy local array overflow in sys_kill and get:
stack-protector: Kernel stack is corrupted in: sys_kill+0x23c/0x23c

TODO:
- Support task switch for different cannary

Signed-off-by: Mao Han <[email protected]>
Signed-off-by: Guo Ren <[email protected]>

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csky: Fixup add zero_fp fixup perf backtrace panic

We need set fp zero to let backtrace know the end. The patch fixup perf
callchain panic problem, because backtrace didn't know what is the end
of f

csky: Fixup add zero_fp fixup perf backtrace panic

We need set fp zero to let backtrace know the end. The patch fixup perf
callchain panic problem, because backtrace didn't know what is the end
of fp.

Signed-off-by: Guo Ren <[email protected]>
Reported-by: Mao Han <[email protected]>

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csky: stacktrace supported.

The gcc option "-mbacktrace" will push fp(r8),lr into stack and we could
unwind the stack with:
fp = *fp
lr = (unsigned int *)fp[1]

Signed-off-by: Guo Ren <ren_guo@c-s

csky: stacktrace supported.

The gcc option "-mbacktrace" will push fp(r8),lr into stack and we could
unwind the stack with:
fp = *fp
lr = (unsigned int *)fp[1]

Signed-off-by: Guo Ren <[email protected]>

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csky: Process management and Signal

This patch adds files related to task_switch, sigcontext, signal,
fpu context switch.

Signed-off-by: Guo Ren <[email protected]>
Cc: Arnd Bergmann <[email protected]

csky: Process management and Signal

This patch adds files related to task_switch, sigcontext, signal,
fpu context switch.

Signed-off-by: Guo Ren <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Eric W. Biederman <[email protected]>

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