Re: [Qemu-devel] [patches] Re: [PULL] RISC-V QEMU Port Submission v8.2

[Peter Maydell]

On 9 March 2018 at 14:28, Peter Maydell <address@hidden> wrote:
> NB: there was a test failure on OpenBSD host:
>
> TEST: tests/qom-test... (pid=64016)
>   /riscv32/qom/spike_v1.9.1:                                           **
> ERROR:/home/qemu/tests/qom-test.c:64:test_properties: assertion
> failed: (qdict_haskey(response, "return"))
> FAIL
>
> but this seems to have been intermittent -- it was only on that one
> host, and I reran the test suite there and it passed fine the second
> time. So it may be nothing to do with your code; we'll see if it
> comes up again.

On a later test run I got this different one; openbsd again:

TEST: tests/test-hmp... (pid=45236)
  /riscv32/hmp/spike_v1.9.1:                                           **
ERROR:/home/qemu/qom/object.c:488:object_new_with_type: assertion
failed: (type != NULL)
Broken pipe
FAIL

My current best theory is that OpenBSD libc's memory allocator
happens to be more sensitive to a memory corruption bug in the risc
code, resulting in intermittent failures if the allocations happen
to come out the wrong way. You do have at least one invalid-write
off the end of a block according to valgrind:

==17441== Invalid write of size 1
==17441==    at 0x26517F: riscv_isa_string (cpu.c:399)
==17441==    by 0x25C14D: create_fdt (spike.c:125)
==17441==    by 0x25C14D: spike_v1_10_0_board_init (spike.c:199)
==17441==    by 0x2CCE0A: machine_run_board_init (machine.c:807)
==17441==    by 0x1BFF28: main (vl.c:4597)
==17441==  Address 0x3055c425 is 0 bytes after a block of size 5 alloc'd
==17441==    at 0x4C2FB55: calloc (in
/usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==17441==    by 0x70C8770: g_malloc0 (in
/lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.2)
==17441==    by 0x26511E: riscv_isa_string (cpu.c:395)
==17441==    by 0x25C14D: create_fdt (spike.c:125)
==17441==    by 0x25C14D: spike_v1_10_0_board_init (spike.c:199)
==17441==    by 0x2CCE0A: machine_run_board_init (machine.c:807)
==17441==    by 0x1BFF28: main (vl.c:4597)

If you can prioritise a patch that fixes the bug in riscv_isa_string()
I'll apply that and hopefully these intermittent failures will go away.

thanks
-- PMM