exit: Add and use make_task_dead.

There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something c

exit: Add and use make_task_dead.

There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure. In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <[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This configuration is obsolete and likely none is really using it.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This configuration is obsolete and likely none is really using it.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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signal: Remove the task parameter from force_sig_fault

As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from fr

signal: Remove the task parameter from force_sig_fault

As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.

The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.

The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:

force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)

Signed-off-by: "Eric W. Biederman" <[email protected]>

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signal/microblaze: Use force_sig_fault where appropriate

Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are f

signal/microblaze: Use force_sig_fault where appropriate

Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.

Simplify this process by using the helper force_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.

In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.

Cc: Michal Simek <[email protected]>
Signed-off-by: "Eric W. Biederman" <[email protected]>

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signal: Ensure every siginfo we send has all bits initialized

Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

signal: Ensure every siginfo we send has all bits initialized

Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <[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: 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]>

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microblaze: Fix coding style issues

Fix coding style issues reported by checkpatch.pl.

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

microblaze: Raise SIGFPE/FPE_INTDIV for div by zero

It fixes the signal nr raised for divizion by zero from
SIGILL to SIGFPE, in accordance to POSIX and other archs.

This came up due to a failed te

microblaze: Raise SIGFPE/FPE_INTDIV for div by zero

It fixes the signal nr raised for divizion by zero from
SIGILL to SIGFPE, in accordance to POSIX and other archs.

This came up due to a failed test in the GCC testsuite.

Signed-off-by: Edgar E. Iglesias <[email protected]>

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microblaze: Fix sparse warning - sw_exceptions

Function sw_exception is linked with asm code.

Warning log:
CHECK arch/microblaze/kernel/exceptions.c
arch/microblaze/kernel/exceptions.c:53:6: warn

microblaze: Fix sparse warning - sw_exceptions

Function sw_exception is linked with asm code.

Warning log:
CHECK arch/microblaze/kernel/exceptions.c
arch/microblaze/kernel/exceptions.c:53:6: warning: symbol 'sw_exception' was not declared. Should it be static?

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

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microblaze: Clear i/dcache for sw breakpoints

There is necessary to flush dcache and invalidate
icache for address where breakpoint (brki r16, 0x18)
was. The reason is that for some cases icache lin

microblaze: Clear i/dcache for sw breakpoints

There is necessary to flush dcache and invalidate
icache for address where breakpoint (brki r16, 0x18)
was. The reason is that for some cases icache line
still keeps brki instruction and it is not updated
by origin instruction maintains by gdbserver.

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

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microblaze: Remove old user debugging gdb stub

Old gdb uses priviledged exception handler to handle
gdb exception. New gdb uses brki r16, 0x18 that's why
we can remove old gdb support.

Signed-off-b

microblaze: Remove old user debugging gdb stub

Old gdb uses priviledged exception handler to handle
gdb exception. New gdb uses brki r16, 0x18 that's why
we can remove old gdb support.

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

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microblaze: Remove pr_<level> uses of KERN_<level>

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

microblaze: Add KGDB support

Kgdb uses brki r16, 0x18 instruction to call
low level _debug_exception function which save
current state to pt_regs and call microblaze_kgdb_break
function. _debug_exce

microblaze: Add KGDB support

Kgdb uses brki r16, 0x18 instruction to call
low level _debug_exception function which save
current state to pt_regs and call microblaze_kgdb_break
function. _debug_exception should be called only from
the kernel space. User space calling is not supported
because user application debugging uses different handling.

pt_regs_to_gdb_regs loads additional special registers
which can't be changed

* Enable KGDB in Kconfig
* Remove ancient not-tested KGDB support
* Remove ancient _debug_exception code from entry.S

Only MMU KGDB support is supported.

Signed-off-by: Michal Simek <[email protected]>
CC: Jason Wessel <[email protected]>
CC: John Williams <[email protected]>
CC: Edgar E. Iglesias <[email protected]>
CC: [email protected]
Acked-by: Jason Wessel <[email protected]>

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microblaze: Support brki rX, 0x18 for user application debugging

This is the first patch which add support for
user application debugging through brki rX, 0x18 vector.

This patch has side effect wh

microblaze: Support brki rX, 0x18 for user application debugging

This is the first patch which add support for
user application debugging through brki rX, 0x18 vector.

This patch has side effect which also remove security issue
to use brki rX, 0x18 to freeze kernel.

Support for old gdb support via priviledged exception
(brk r0, r0) is still there. It will be remove in future.

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

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microblaze: fix divide by zero exception message

Fix divide exception message to say "divide by zero".

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

microblaze: fix divide by zero exception message

Fix divide exception message to say "divide by zero".

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

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microblaze: Generate correct signal and siginfo for integer div-by-zero

Signed-off-by: John Williams <[email protected]>

microblaze: Don't be noisy when userspace causes hardware exceptions

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

microblaze_mmu_v2: Add MMU related exceptions handling

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

microblaze_v8: exception handling

Reviewed-by: Ingo Molnar <[email protected]>
Acked-by: Stephen Neuendorffer <[email protected]>
Acked-by: John Linn <[email protected]>
Acked-by: John

microblaze_v8: exception handling

Reviewed-by: Ingo Molnar <[email protected]>
Acked-by: Stephen Neuendorffer <[email protected]>
Acked-by: John Linn <[email protected]>
Acked-by: John Williams <[email protected]>
Signed-off-by: Michal Simek <[email protected]>

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