[Qemu-devel] Qemu user mode failure

[Qemu-devel] Qemu user mode failure

[Pavel Shamis]

Dear QEMU Developers,

I'm trying to build and run UCX project
(https://github.com/openucx/ucx) under qemu user mode.
I have no problem to build the project, but whenever I'm trying to
run/use binaries from the project
I get the following error:

./bin/ucx_info
qemu-aarch64-static: qemu-2.5.0/translate-all.c:1888: page_set_flags:
Assertion `start < end' failed.
qemu: uncaught target signal 6 (Aborted) - core dumped
Aborted (core dumped)

Version:
qemu-aarch64-static
qemu-aarch64 version 2.5.0, Copyright (c) 2003-2008 Fabrice Bellard

Please let me know if you have any idea how to fix this issue.

Best,
Pasha

Re: [Qemu-devel] Qemu user mode failure

[Peter Maydell]

On 29 January 2016 at 19:18, Pavel Shamis <pasharesearch@gmail.com> wrote:
> Dear QEMU Developers,
>
> I'm trying to build and run UCX project
> (https://github.com/openucx/ucx) under qemu user mode.
> I have no problem to build the project, but whenever I'm trying to
> run/use binaries from the project
> I get the following error:
>
> ./bin/ucx_info
> qemu-aarch64-static: qemu-2.5.0/translate-all.c:1888: page_set_flags:
> Assertion `start < end' failed.
> qemu: uncaught target signal 6 (Aborted) - core dumped
> Aborted (core dumped)

This turns out to be a bug in QEMU where we were not correctly
handling an attempt by the guest to do shmdt(0). This isn't a
valid thing to do, but we were not handling it gracefully. I've just
sent a patch to the list which corrects our behaviour so we now
fail the syscall EINVAL rather than asserting. With this the
ucx_info program prints out its help message when run.
(http://patchwork.ozlabs.org/patch/580923/)

You might want to investigate why you're trying to shmdt(0) --
maybe there's some code that's not handling an error properly ?
Looking at QEMU's strace output this seems to happen shortly after
a failed shmat() syscall.

thanks
-- PMM