Re: [Qemu-devel] Bug in mips user-linux

[Thomas Huth]

On 10.10.2016 03:01, Torbjörn Granlund wrote:
> This is a long-standing issue; I've reproduced it in 2.5.0, 2.6.2, and
> 2.7.0.
> 
> Command used:  qemu-mipsn32 ./reuse
> 
> The binary file 'reuse' is attached.
> 
> Funnily enough, it does not fail every time.  (I would expect user-level
> emulation to be pretty deterministic, but alas, this is not.)
> 
> When it fails, it either says,
> 
>   qemu: uncaught target signal 11 (Segmentation fault) - core dumped
>   Segmentation fault
> 
> or unfrequently,
> 
>   mipsn: /var/tmp/build.2567/qemu-2.6.2/translate-all.c:1884: page_set_flags: 
> Assertion `start < end' failed.
>   qemu: uncaught target signal 6 (Aborted) - core dumped
> 
> while the same binary runs fine on hardware as well as
> emulated systems running under qemu-system-mips64.
> 
> The failures only happen for the n32 ABI (not o32 or 64).
> 
> This test case comes from GMP (default gcc compile of
> gmp/tests/mpz/reuse.c).
> 
> (Host and guest systems all run Debian 8.)

Could you maybe get a proper backtrace of the crash with gdb? I guess
that would help to track down the problem.
And please make sure to copy the MIPS maintainers on CC: when reporting
such issues (see MAINTAINERS file), otherwise your mail might get lost
in the high traffic of the qemu-devel mailing list.

 Thanks,
  Thomas