[PATCH 4.4 08/28] MIPS: math-emu: Remove pr_err() calls from fpu_emu()

From: Greg Kroah-Hartman
Date: Mon Oct 16 2017 - 12:15:37 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@xxxxxxxxxx>

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 <paul.burton@xxxxxxxxxx>
Fixes: f8c3c6717a71 ("MIPS: math-emu: Add support for the CMP.condn.fmt R6 instruction")
Cc: linux-mips@xxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/17253/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/mips/math-emu/cp1emu.c | 2 --
1 file changed, 2 deletions(-)

--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -2360,7 +2360,6 @@ dcopuop:
break;
default:
/* Reserved R6 ops */
- pr_err("Reserved MIPS R6 CMP.condn.S operation\n");
return SIGILL;
}
}
@@ -2434,7 +2433,6 @@ dcopuop:
break;
default:
/* Reserved R6 ops */
- pr_err("Reserved MIPS R6 CMP.condn.D operation\n");
return SIGILL;
}
}