linux-stable.git/arch/mips/include, branch v3.18.92

MIPS: End asm function prologue macros with .insn

2017-11-21T08:01:06+00:00

[ Upstream commit 08889582b8aa0bbc01a1e5a0033b9f98d2e11caa ]

When building a kernel targeting a microMIPS ISA, recent GNU linkers
will fail the link if they cannot determine that the target of a branch
or jump is microMIPS code, with errors such as the following:

    mips-img-linux-gnu-ld: arch/mips/built-in.o: .text+0x542c:
    Unsupported jump between ISA modes; consider recompiling with
    interlinking enabled.
    mips-img-linux-gnu-ld: final link failed: Bad value

or:

    ./arch/mips/include/asm/uaccess.h:1017: warning: JALX to a
    non-word-aligned address

Placing anything other than an instruction at the start of a function
written in assembly appears to trigger such errors. In order to prepare
for allowing us to follow function prologue macros with an EXPORT_SYMBOL
invocation, end the prologue macros (LEAD, NESTED & FEXPORT) with a
.insn directive. This ensures that the start of the function is marked
as code, which always makes sense for functions & safely prevents us
from hitting the link errors described above.

Signed-off-by: Paul Burton 
Reviewed-by: Maciej W. Rozycki 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14508/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix CM region target definitions

2017-11-15T09:04:13+00:00

commit 6a6cba1d945a7511cdfaf338526871195e420762 upstream.

The default CM target field in the GCR_BASE register is encoded with 0
meaning memory & 1 being reserved. However the definitions we use for
those bits effectively get these two values backwards - likely because
they were copied from the definitions for the CM regions where the
target is encoded differently. This results in use setting up GCR_BASE
with the reserved target value by default, rather than targeting memory
as intended. Although we currently seem to get away with this it's not a
great idea to rely upon.

Fix this by changing our macros to match the documentated target values.

The incorrect encoding became used as of commit 9f98f3dd0c51 ("MIPS: Add
generic CM probe & access code") in the Linux v3.15 cycle, and was
likely carried forwards from older but unused code introduced by
commit 39b8d5254246 ("[MIPS] Add support for MIPS CMP platform.") in the
v2.6.26 cycle.

Fixes: 9f98f3dd0c51 ("MIPS: Add generic CM probe & access code")
Signed-off-by: Paul Burton 
Reported-by: Matt Redfearn 
Reviewed-by: James Hogan 
Cc: Matt Redfearn 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc:  # v3.15+
Patchwork: https://patchwork.linux-mips.org/patch/17562/
Signed-off-by: James Hogan 
[jhogan@kernel.org: Backported 3.15..4.13]
Signed-off-by: Greg Kroah-Hartman

Make asm/word-at-a-time.h available on all architectures

2017-08-11T16:30:13+00:00

commit a6e2f029ae34f41adb6ae3812c32c5d326e1abd2 upstream.

Added the x86 implementation of word-at-a-time to the
generic version, which previously only supported big-endian.

Omitted the x86-specific load_unaligned_zeropad(), which in
any case is also not present for the existing BE-only
implementation of a word-at-a-time, and is only used under
CONFIG_DCACHE_WORD_ACCESS.

Added as a "generic-y" to the Kbuilds of all architectures
that didn't previously have it.

Signed-off-by: Chris Metcalf 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix unaligned PC interpretation in `compute_return_epc'

2017-07-27T22:03:27+00:00

commit 11a3799dbeb620bf0400b1fda5cc2c6bea55f20a upstream.

Fix a regression introduced with commit fb6883e5809c ("MIPS: microMIPS:
Support handling of delay slots.") and defer to `__compute_return_epc'
if the ISA bit is set in EPC with non-MIPS16, non-microMIPS hardware,
which will then arrange for a SIGBUS due to an unaligned instruction
reference.  Returning EPC here is never correct as the API defines this
function's result to be either a negative error code on failure or one
of 0 and BRANCH_LIKELY_TAKEN on success.

Fixes: fb6883e5809c ("MIPS: microMIPS: Support handling of delay slots.")
Signed-off-by: Maciej W. Rozycki 
Cc: James Hogan 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16395/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: UAPI: Ignore __arch_swab{16,32,64} when using MIPS16

2017-07-15T08:14:38+00:00

commit 71a0a72456b48de972d7ed613b06a22a3aa9057f upstream.

Some GCC versions (e.g. 4.8.3) can incorrectly inline a function with
MIPS32 instructions into another function with MIPS16 code [1], causing
the assembler to genereate incorrect binary code or fail right away
complaining about unrecognized opcode.

In the case of __arch_swab{16,32}, when inlined by the compiler with
flags `-mips32r2 -mips16 -Os', the assembler can fail with the following
error.

    {standard input}:79: Error: unrecognized opcode `wsbh $2,$2'

For performance concerns and to workaround the issue already existing in
older compilers, just ignore these 2 functions when compiling with
mips16 enabled.

 [1] Inlining nomips16 function into mips16 function can result in
     undefined builtins, https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55777

Signed-off-by: Yousong Zhou 
Cc: Maciej W. Rozycki 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11241/
Signed-off-by: Ralf Baechle 
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

MIPS: asm: compiler: Add new macros to set ISA and arch asm annotations

2017-04-30T03:49:15+00:00

commit be5136988e25ae0dc8379fcb937efc63d87aba9e upstream.

There are certain places where the code uses .set mips32 or .set mips64
or .set arch=r4000. In preparation of MIPS R6 support, and in order to
use as less #ifdefs as possible, we define new macros to set similar
annotations for MIPS R6.

Signed-off-by: Markos Chandras 
Cc: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

mips: copy_from_user() must zero the destination on access_ok() failure

2016-10-06T02:40:20+00:00

[ Upstream commit e69d700535ac43a18032b3c399c69bf4639e89a2 ]

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin

MIPS: Add a missing ".set pop" in an early commit

2016-10-06T02:40:20+00:00

[ Upstream commit 3cbc6fc9c99f1709203711f125bc3b79487aba06 ]

Commit 842dfc11ea9a21 ("MIPS: Fix build with binutils 2.24.51+") missing
a ".set pop" in macro fpu_restore_16even, so add it.

Signed-off-by: Huacai Chen 
Acked-by: Manuel Lauss 
Cc: Steven J . Hill 
Cc: Fuxin Zhang 
Cc: Zhangjin Wu 
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.18+
Patchwork: https://patchwork.linux-mips.org/patch/14210/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin

MIPS: paravirt: Fix undefined reference to smp_bootstrap

2016-10-06T02:40:20+00:00

[ Upstream commit 951c39cd3bc0aedf67fbd8fb4b9380287e6205d1 ]

If the paravirt machine is compiles without CONFIG_SMP, the following
linker error occurs

arch/mips/kernel/head.o: In function `kernel_entry':
(.ref.text+0x10): undefined reference to `smp_bootstrap'

due to the kernel entry macro always including SMP startup code.
Wrap this code in CONFIG_SMP to fix the error.

Signed-off-by: Matt Redfearn 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # 3.16+
Patchwork: https://patchwork.linux-mips.org/patch/14212/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin

MIPS: Fix page table corruption on THP permission changes.

2016-07-20T15:35:52+00:00

[ Upstream commit 88d02a2ba6c52350f9a73ff1b01a5be839c3ca17 ]

When the core THP code is modifying the permissions of a huge page it
calls pmd_modify(), which unfortunately was clearing the _PAGE_HUGE bit
of the page table entry.  The result can be kernel messages like:

mm/memory.c:397: bad pmd 000000040080004d.
mm/memory.c:397: bad pmd 00000003ff00004d.
mm/memory.c:397: bad pmd 000000040100004d.

or:

------------[ cut here ]------------
WARNING: at mm/mmap.c:3200 exit_mmap+0x150/0x158()
Modules linked in: ipv6 at24 octeon3_ethernet octeon_srio_nexus m25p80
CPU: 12 PID: 1295 Comm: pmderr Not tainted 3.10.87-rt80-Cavium-Octeon #4
Stack : 0000000040808000 0000000014009ce1 0000000000400004 ffffffff81076ba0
          0000000000000000 0000000000000000 ffffffff85110000 0000000000000119
          0000000000000004 0000000000000000 0000000000000119 43617669756d2d4f
          0000000000000000 ffffffff850fda40 ffffffff85110000 0000000000000000
          0000000000000000 0000000000000009 ffffffff809207a0 0000000000000c80
          ffffffff80f1bf20 0000000000000001 000000ffeca36828 0000000000000001
          0000000000000000 0000000000000001 000000ffeca7e700 ffffffff80886924
          80000003fd7a0000 80000003fd7a39b0 80000003fdea8000 ffffffff80885780
          80000003fdea8000 ffffffff80f12218 000000000000000c 000000000000050f
          0000000000000000 ffffffff80865c4c 0000000000000000 0000000000000000
          ...
Call Trace:
[] show_stack+0x6c/0xf8
[] warn_slowpath_common+0x78/0xa8
[] exit_mmap+0x150/0x158
[] mmput+0x5c/0x110
[] do_exit+0x230/0xa68
[] do_group_exit+0x54/0x1d0
[] __wake_up_parent+0x0/0x18

---[ end trace c7b38293191c57dc ]---
BUG: Bad rss-counter state mm:80000003fa168000 idx:1 val:1536

Fix by not clearing _PAGE_HUGE bit.

Signed-off-by: David Daney 
Tested-by: Aaro Koskinen 
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13687/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin