[RFE] option to suppress gemu_log() output

[Thomas Moschny]

With user mode emulation, messages from genu_log() are emitted unconditionally to stderr. I didn't find a way to suppress them. It would be nice to have options similar to the -D/-d options to be able to filter and/or redirect the output.

My use case is chroot/container execution for different architectures via binfmt. In this case it will appear as if the binary in question had emitted messages like "Unsupported setsockopt ..." to stderr while in fact the message came from qemu-*-static.

[Philippe Mathieu-Daudé (philmd)]

This series might be helpful:
https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg02067.html

[Alex Bennée (ajbennee)]

The -d/-D options should work in linux-user as well. You can also set QEMU_LOG_FILENAME and QEMU_LOG environment variables. Do these not work for you?

[Alex Bennée (ajbennee)]

Although arguably the line:

  gemu_log("Unsupported setsockopt level=%d optname=%d\n", level, optname);

Could be

  qemu_log_mask(LOG_UNIMP,....)

Not sure where gemu_log is used, it seems to be strace related.

[Thomas Moschny (moschny)]

Indeed I think gemu_log() is the problem here.

[Thomas Huth (th-huth)]

This is an automated cleanup. This bug report has been moved to QEMU's
new bug tracker on gitlab.com and thus gets marked as 'expired' now.
Please continue with the discussion here:

 https://gitlab.com/qemu-project/qemu/-/issues/171