Re: [Qemu-devel] [Bug 902148] [NEW] qemu-img V1.0 hangs on creating Image (0.15.1 runs)

[Stefan Hajnoczi <stefanha@gmail.com>]

On Fri, Dec 9, 2011 at 1:10 PM, Michael Niehren
<902148@bugs.launchpad.net> wrote:
> Strace on the hanging qemu-img ends on:
>
> select(5, [4], [], NULL, NULL)          = 1 (in [4])
> read(4, "\0", 16)                       = 1
> close(3)                                = 0
> open("test.img", O_RDONLY|O_NONBLOCK)   = 3
> fstat(3, {st_mode=S_IFREG|0644, st_size=131072, ...}) = 0
> close(3)                                = 0
> open("test.img", O_RDONLY|O_NONBLOCK)   = 3
> fstat(3, {st_mode=S_IFREG|0644, st_size=131072, ...}) = 0
> close(3)                                = 0
> stat("test.img", {st_mode=S_IFREG|0644, st_size=131072, ...}) = 0
> open("test.img", O_RDWR|O_CLOEXEC)      = 3
> lseek(3, 0, SEEK_END)                   = 131072
>
> next line in the strace on working qemu-img V0.15.1 is:
> pread(3, "QFI\373\0\0\0\2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\20\0\0\0\0\0\0\0\0"..., 512, 0) = 512
> ...

When it hangs does it consume CPU?

Please attach gdb to the process and capture a backtrace:
$ gdb -p $PID_OF_QEMU
(gdb) thread apply all bt

Stefan