linux.git/arch/arc/kernel/unaligned.c, branch v6.12.80

arc: get rid of private asm/unaligned.h

2024-10-02T21:22:47+00:00

Declarations local to arch/*/kernel/*.c are better off *not* in a public
header - arch/arc/kernel/unaligned.h is just fine for those
bits.

Unlike the parisc case, here we have an extra twist - asm/mmu.h
has an implicit dependency on struct pt_regs, and in some users
that used to be satisfied by include of asm/ptrace.h from
asm/unaligned.h (note that asm/mmu.h itself did _not_ pull asm/unaligned.h
- it relied upon the users having pulled asm/unaligned.h before asm/mmu.h
got there).

Seeing that asm/mmu.h only wants struct pt_regs * arguments in
an extern, just pre-declare it there - less brittle that way.

With that done _all_ asm/unaligned.h instances are reduced to include
of asm-generic/unaligned.h and can be removed - unaligned.h is in
mandatory-y in include/asm-generic/Kbuild.

What's more, we can move asm-generic/unaligned.h to linux/unaligned.h
and switch includes of  to ; that's
better off as an auto-generated commit, though, to be done by Linus
at -rc1 time next cycle.

Acked-by: Vineet Gupta 
Signed-off-by: Al Viro

ARC: fix typos in comments

2022-04-18T19:20:23+00:00

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall 
Signed-off-by: Vineet Gupta

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Enrico Weigelt 
Reviewed-by: Kate Stewart 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ARC: [arcompact] brown paper bag bug in unaligned access delay slot fixup

2017-02-07T18:02:01+00:00

Reported-by: Jo-Philipp Wich 
Fixes: 9aed02feae57bf7 ("ARC: [arcompact] handle unaligned access delay slot")
Cc: linux-kernel@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta 
Signed-off-by: Linus Torvalds

ARC: [arcompact] handle unaligned access delay slot corner case

2017-01-27T18:54:20+00:00

After emulating an unaligned access in delay slot of a branch, we
pretend as the delay slot never happened - so return back to actual
branch target (or next PC if branch was not taken).

Curently we did this by handling STATUS32.DE, we also need to clear the
BTA.T bit, which is disregarded when returning from original misaligned
exception, but could cause weirdness if it took the interrupt return
path (in case interrupt was acive too)

One ARC700 customer ran into this when enabling unaligned access fixup
for kernel mode accesses as well

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta

ARC: change some branchs to jumps to resolve linkage errors

2015-08-20T13:23:15+00:00

When kernel's binary becomes large enough (32M and more) errors
may occur during the final linkage stage. It happens because
the build system uses short relocations for ARC  by default.
This problem may be easily resolved by passing -mlong-calls
option to GCC to use long absolute jumps (j) instead of short
relative branchs (b).

But there are fragments of pure assembler code exist which use
branchs in inappropriate places and cause a linkage error because
of relocations overflow.

First of these fragments is .fixup insertion in futex.h and
unaligned.c. It inserts a code in the separate section (.fixup)
with branch instruction. It leads to the linkage error when
kernel becomes large.

Second of these fragments is calling scheduler's functions
(common kernel code) from entry.S of ARC's code. When kernel's
binary becomes large it may lead to the linkage error because
scheduler may occur far enough from ARC's code in the final
binary.

Signed-off-by: Yuriy Kolerov 
Signed-off-by: Vineet Gupta

ARC: perf: Enable generic software events

2015-02-27T04:45:01+00:00

Signed-off-by: Vineet Gupta

ARC: Handle zero-overhead-loop in unaligned access handler

2013-09-27T10:58:23+00:00

If a load or store is the last instruction in a zero-overhead-loop, and
it's misaligned, the loop would execute only once.

This fixes that problem.

Signed-off-by: Mischa Jonker 
Signed-off-by: Vineet Gupta

ARC: Handle un-aligned user space access in BE.

2013-09-05T05:01:11+00:00

Adding endian awarness to un-aligned access exception handling.

Signed-off-by: Noam Camus 
Signed-off-by: Vineet Gupta

ARC: Remove explicit passing around of ECR

2013-06-26T10:00:50+00:00

With ECR now part of pt_regs

* No need to propagate from lowest asm handlers as arg
* No need to save it in tsk->thread.cause_code
* Avoid bit chopping to access the bit-fields

More code consolidation, cleanup

Signed-off-by: Vineet Gupta