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bhyve: Set SO_REUSEADDR on the gdb stub socket
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Authored by markj on Apr 29 2021, 3:52 PM.

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Summary

When using bhyve's gdb stub to debug some changes to the kernel's early
boot code, I frequently hit an error when reconnecting gdb. Set
SO_REUSEADDR to mitigate this, as we do for the VNC server.

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rG FreeBSD src repository
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markj requested review of this revision.Apr 29 2021, 3:52 PM
usr.sbin/bhyve/gdb.c
1848

Why no check for errors from setsockopt call?

jhb added a subscriber: jhb.
jhb added inline comments.
usr.sbin/bhyve/gdb.c
1848

Because failure isn't fatal probably? The VNC code in rfb.c doesn't check for errors either. In practice I don't think SO_REUSEADDR can fail for a TCP socket on FreeBSD.

This revision is now accepted and ready to land.Apr 29 2021, 4:54 PM
usr.sbin/bhyve/gdb.c
1848

This was exactly my reasoning.

usr.sbin/bhyve/gdb.c
1848

The man page clearly indicates it can fail, and the one in dbgport.c does check status.

usr.sbin/bhyve/gdb.c
1848

It will only fail for generic reasons, like if s is not a socket or a copyin of the optval fails.

This revision was automatically updated to reflect the committed changes.