MIPS: Only use current_stack_pointer on GCC

Unfortunately, Clang did not have support for "sp" as a global register
definition, and was crashing after the addition of current_stack_pointer.
This has

MIPS: Only use current_stack_pointer on GCC

Unfortunately, Clang did not have support for "sp" as a global register
definition, and was crashing after the addition of current_stack_pointer.
This has been fixed in Clang 14, but earlier Clang versions need to
avoid this code, so add a versioned test and revert back to the
open-coded asm instances. Fixes Clang build error:

fatal error: error in backend: Invalid register name global variable

Fixes: 200ed341b864 ("mips: Implement "current_stack_pointer"")
Reported-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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mips: Implement "current_stack_pointer"

To follow the existing per-arch conventions replace open-coded uses
of asm "sp" as "current_stack_pointer". This will let it be used in
non-arch places (like

mips: Implement "current_stack_pointer"

To follow the existing per-arch conventions replace open-coded uses
of asm "sp" as "current_stack_pointer". This will let it be used in
non-arch places (like HARDENED_USERCOPY).

Cc: Thomas Bogendoerfer <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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mips: lib: uncached: fix non-standard usage of variable 'sp'

When building mips tinyconfig with clang the following warning show up:

arch/mips/lib/uncached.c:45:6: warning: variable 'sp' is uniniti

mips: lib: uncached: fix non-standard usage of variable 'sp'

When building mips tinyconfig with clang the following warning show up:

arch/mips/lib/uncached.c:45:6: warning: variable 'sp' is uninitialized when used here [-Wuninitialized]
if (sp >= (long)CKSEG0 && sp < (long)CKSEG2)
^~
arch/mips/lib/uncached.c:40:18: note: initialize the variable 'sp' to silence this warning
register long sp __asm__("$sp");
^
= 0
1 warning generated.

Rework to make an explicit inline move, instead of the non-standard use
of specifying registers for local variables. This is what's written
from the gcc-10 manual [1] about specifying registers for local
variables:

"6.47.5.2 Specifying Registers for Local Variables
.................................................
[...]

"The only supported use for this feature is to specify registers for
input and output operands when calling Extended 'asm' (*note Extended
Asm::). [...]".

[1] https://docs.w3cub.com/gcc~10/local-register-variables
Signed-off-by: Anders Roxell <[email protected]>
Reported-by: Nathan Chancellor <[email protected]>
Reported-by: Naresh Kamboju <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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mips: delete non-required instances of include <linux/init.h>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left

mips: delete non-required instances of include <linux/init.h>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <[email protected]>
Signed-off-by: John Crispin <[email protected]>
Patchwork: http://patchwork.linux-mips.org/patch/6320/

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MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code

commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM

MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code

commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings. In any case, they are temporary and harmless.

Here, we remove all the MIPS __cpuinit from C code and __CPUINIT
from asm files. MIPS is interesting in this respect, because there
are also uasm users hiding behind their own renamed versions of the
__cpuinit macros.

[1] https://lkml.org/lkml/2013/5/20/589

[[email protected]: Folded in Paul's followup fix.]

Signed-off-by: Paul Gortmaker <[email protected]>
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/5494/
Patchwork: https://patchwork.linux-mips.org/patch/5495/
Patchwork: https://patchwork.linux-mips.org/patch/5509/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Whitespace cleanup.

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-b

MIPS: Whitespace cleanup.

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: Ralf Baechle <[email protected]>

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[MIPS] Fix loads of section missmatches

Signed-off-by: Ralf Baechle <[email protected]>

[MIPS] Put cast inside macro instead of all the callers

Since all the callers of the PHYS_TO_XKPHYS macro call with a constant,
put the cast to LL inside the macro where it really should be rather
t

[MIPS] Put cast inside macro instead of all the callers

Since all the callers of the PHYS_TO_XKPHYS macro call with a constant,
put the cast to LL inside the macro where it really should be rather
than in all the callers. This makes macros like PHYS_TO_XKSEG_UNCACHED
work without gcc whining.

Signed-off-by: Andrew Sharp <[email protected]>
Signed-off-by: Ralf Baechle <[email protected]>

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[MIPS] Include cacheflush.h in uncache.c

This fixes this sparse warning:

arch/mips/lib/uncached.c:38:22: warning: symbol 'run_uncached' was not declared. Should it be static?

Signed-off-by: Atsush

[MIPS] Include cacheflush.h in uncache.c

This fixes this sparse warning:

arch/mips/lib/uncached.c:38:22: warning: symbol 'run_uncached' was not declared. Should it be static?

Signed-off-by: Atsushi Nemoto <[email protected]>
Signed-off-by: Ralf Baechle <[email protected]>

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[MIPS] Fix warnings in run_uncached on 32bit kernel

arch/mips/lib/uncached.c: In function 'run_uncached':
arch/mips/lib/uncached.c:47: warning: comparison is always true due to limited range of data

[MIPS] Fix warnings in run_uncached on 32bit kernel

arch/mips/lib/uncached.c: In function 'run_uncached':
arch/mips/lib/uncached.c:47: warning: comparison is always true due to limited range of data type
arch/mips/lib/uncached.c:48: warning: comparison is always false due to limited range of data type
arch/mips/lib/uncached.c:57: warning: comparison is always true due to limited range of data type
arch/mips/lib/uncached.c:58: warning: comparison is always false due to limited range of data type

Signed-off-by: Yoichi Yuasa <[email protected]>
Signed-off-by: Ralf Baechle <[email protected]>

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Better interface to run uncached cache setup code.

Signed-off-by: Thiemo Seufer <[email protected]>
Signed-off-by: Ralf Baechle <[email protected]>