linux-toradex.git/arch/mips, branch v4.4.93

MIPS: math-emu: Remove pr_err() calls from fpu_emu()

2017-10-18T07:20:41+00:00

commit ca8eb05b5f332a9e1ab3e2ece498d49f4d683470 upstream.

The FPU emulator includes 2 calls to pr_err() which are triggered by
invalid instruction encodings for MIPSr6 cmp.cond.fmt instructions.
These cases are not kernel errors, merely invalid instructions which are
already handled by delivering a SIGILL which will provide notification
that something failed in cases where that makes sense.

In cases where that SIGILL is somewhat expected & being handled, for
example when crashme happens to generate one of the affected bad
encodings, the message is printed with no useful context about what
triggered it & spams the kernel log for no good reason.

Remove the pr_err() calls to make crashme run silently & treat the bad
encodings the same way we do others, with a SIGILL & no further kernel
log output.

Signed-off-by: Paul Burton 
Fixes: f8c3c6717a71 ("MIPS: math-emu: Add support for the CMP.condn.fmt R6 instruction")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17253/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: IRQ Stack: Unwind IRQ stack onto task stack

2017-10-08T08:14:19+00:00

[ Upstream commit db8466c581cca1a08b505f1319c3ecd246f16fa8 ]

When the separate IRQ stack was introduced, stack unwinding only
proceeded as far as the top of the IRQ stack, leading to kernel
backtraces being less useful, lacking the trace of what was interrupted.

Fix this by providing a means for the kernel to unwind the IRQ stack
onto the interrupted task stack. The processor state is saved to the
kernel task stack on interrupt. The IRQ_STACK_START macro reserves an
unsigned long at the top of the IRQ stack where the interrupted task
stack pointer can be saved. After the active stack is switched to the
IRQ stack, save the interrupted tasks stack pointer to the reserved
location.

Fix the stack unwinding code to look for the frame being the top of the
IRQ stack and if so get the next frame from the saved location. The
existing test does not work with the separate stack since the ra is no
longer pointed at ret_from_{irq,exception}.

The test to stop unwinding the stack 32 bytes from the top of a stack
must be modified to allow unwinding to continue up to the location of
the saved task stack pointer when on the IRQ stack. The low / high marks
of the stack are set depending on whether the sp is on an irq stack or
not.

Signed-off-by: Matt Redfearn 
Cc: Paolo Bonzini 
Cc: Marcin Nowakowski 
Cc: Masanari Iida 
Cc: Chris Metcalf 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Ingo Molnar 
Cc: Jason A. Donenfeld 
Cc: Andrew Morton 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15788/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

MIPS: Lantiq: Fix another request_mem_region() return code check

2017-10-08T08:14:18+00:00

[ Upstream commit 98ea51cb0c8ce009d9da1fd7b48f0ff1d7a9bbb0 ]

Hauke already fixed a couple of them, but one instance remains
that checks for a negative integer when it should check
for a NULL pointer:

arch/mips/lantiq/xway/sysctrl.c: In function 'ltq_soc_init':
arch/mips/lantiq/xway/sysctrl.c:473:19: error: ordered comparison of pointer with integer zero [-Werror=extra]

Fixes: 6e807852676a ("MIPS: Lantiq: Fix check for return value of request_mem_region()")
Signed-off-by: Arnd Bergmann 
Cc: John Crispin 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15043/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

MIPS: ralink: Fix incorrect assignment on ralink_soc

2017-10-08T08:14:16+00:00

[ Upstream commit 08d90c81b714482dceb5323d14f6617bcf55ee61 ]

ralink_soc sould be assigned to RT3883_SOC, replace incorrect
comparision with assignment.

Signed-off-by: Colin Ian King 
Fixes: 418d29c87061 ("MIPS: ralink: Unify SoC id handling")
Cc: John Crispin 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14903/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

MIPS: Ensure bss section ends on a long-aligned address

2017-10-08T08:14:16+00:00

[ Upstream commit 3f00f4d8f083bc61005d0a1ef592b149f5c88bbd ]

When clearing the .bss section in kernel_entry we do so using LONG_S
instructions, and branch whilst the current write address doesn't equal
the end of the .bss section minus the size of a long integer. The .bss
section always begins at a long-aligned address and we always increment
the write pointer by the size of a long integer - we therefore rely upon
the .bss section ending at a long-aligned address. If this is not the
case then the long-aligned write address can never be equal to the
non-long-aligned end address & we will continue to increment past the
end of the .bss section, attempting to zero the rest of memory.

Despite this requirement that .bss end at a long-aligned address we pass
0 as the end alignment requirement to the BSS_SECTION macro and thus
don't guarantee any particular alignment, allowing us to hit the error
condition described above.

Fix this by instead passing 8 bytes as the end alignment argument to
the BSS_SECTION macro, ensuring that the end of the .bss section is
always at least long-aligned.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14526/
Signed-off-by: Ralf Baechle 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: MINA.: Fix some cases of infinity and zero inputs

2017-09-27T09:00:13+00:00

commit 304bfe473e70523e591fb1c9223289d355e0bdcb upstream.

Fix following special cases for MINA>.:

  - if one of the inputs is zero, and the other is subnormal, normal,
    or infinity, the  value of the former should be returned (that is,
    a zero).
  - if one of the inputs is infinity, and the other input is normal,
    or subnormal, the value of the latter should be returned.

The previous implementation's logic for such cases was incorrect - it
appears as if it implements MAXA, and not MINA instruction.

A relevant example:

MINA.S fd,fs,ft:
  If fs contains 100.0, and ft contains 0.0, fd is going to contain
  0.0 (without this patch, it used to contain 100.0).

Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Reviewed-by: James Hogan 
Cc: Bo Hu 
Cc: Douglas Leung 
Cc: Jin Qian 
Cc: Paul Burton 
Cc: Petar Jovanovic 
Cc: Raghu Gandham 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16885/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: .: Fix cases of both infinite inputs

2017-09-27T09:00:13+00:00

commit 3444c4eb534c20e44f0d6670b34263efaf8b531f upstream.

Fix the value returned by . fd,fs,ft, if both inputs
are infinite. The previous implementation returned always the value
contained in ft in such cases. The correct behavior is specified
in Mips instruction set manual and is as follows:

    fs    ft        MAXA     MINA
  ---------------------------------
    inf   inf        inf      inf
    inf  -inf        inf     -inf
   -inf   inf        inf     -inf
   -inf  -inf       -inf     -inf

A relevant example:

MAXA.S fd,fs,ft:
  If fs contains +inf, and ft contains -inf, fd is going to contain
  +inf (without this patch, it used to contain -inf).

Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Reviewed-by: James Hogan 
Cc: Bo Hu 
Cc: Douglas Leung 
Cc: Jin Qian 
Cc: Paul Burton 
Cc: Petar Jovanovic 
Cc: Raghu Gandham 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16884/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: .: Fix cases of input values with opposite signs

2017-09-27T09:00:13+00:00

commit 1a41b3b441508ae63b1a9ec699ec94065739eb60 upstream.

Fix the value returned by ., if the inputs are normal
fp numbers of the same absolute value, but opposite signs.

A relevant example:

MAXA.S fd,fs,ft:
  If fs contains -3.0, and ft contains +3.0, fd is going to contain
  +3.0 (without this patch, it used to contain -3.0).

Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Reviewed-by: James Hogan 
Cc: Bo Hu 
Cc: Douglas Leung 
Cc: Jin Qian 
Cc: Paul Burton 
Cc: Petar Jovanovic 
Cc: Raghu Gandham 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16883/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: .: Fix cases of both inputs negative

2017-09-27T09:00:13+00:00

commit aabf5cf02e22ebc4e541adf835910f388b6c3e65 upstream.

Fix the value returned by ., if both inputs are negative
normal fp numbers. The previous logic did not take into account that
if both inputs have the same sign, there should be separate treatment
of the cases when both inputs are negative and when both inputs are
positive.

A relevant example:

MAX.S fd,fs,ft:
  If fs contains -5.0, and ft contains -7.0, fd is going to contain
  -5.0 (without this patch, it used to contain -7.0).

Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Reviewed-by: James Hogan 
Cc: Bo Hu 
Cc: Douglas Leung 
Cc: Jin Qian 
Cc: Paul Burton 
Cc: Petar Jovanovic 
Cc: Raghu Gandham 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16882/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: .: Fix cases of both inputs zero

2017-09-27T09:00:13+00:00

commit 15560a58bfd4ff82cdd16b2270d4ef9b06d2cc4d upstream.

Fix the value returned by ., if both inputs
are zeros. The right behavior in such cases is stated in instruction
reference manual and is as follows:

   fs  ft       MAX     MIN       MAXA    MINA
  ---------------------------------------------
    0   0        0       0         0       0
    0  -0        0      -0         0      -0
   -0   0        0      -0         0      -0
   -0  -0       -0      -0        -0      -0

Prior to this patch, some of the above cases were yielding correct
results. However, for the sake of code consistency, all such cases
are rewritten in this patch.

A relevant example:

MAX.S fd,fs,ft:
  If fs contains +0.0, and ft contains -0.0, fd is going to contain
  +0.0 (without this patch, it used to contain -0.0).

Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Reviewed-by: James Hogan 
Cc: Bo Hu 
Cc: Douglas Leung 
Cc: Jin Qian 
Cc: Paul Burton 
Cc: Petar Jovanovic 
Cc: Raghu Gandham 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16881/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman