Re: [Libguestfs] [libnbd PATCH v4 6/6] states: Break deadlock if server goofs on extended replies

On 7/21/23 18:08, Eric Blake wrote: > One of the benefits of extended replies is that we can do a > fixed-length read for the entire header of every server reply, which > is fewer syscalls than the split-read approach required by structured > replies. But one of the drawbacks of doing a large read is that if > the server is non-compliant (not a problem for normal servers, but > something I hit rather more than I'd like to admit while developing > extended header support in servers), nbd_pwrite() and friends will > deadlock if the server replies with the wrong header. Add in some > code to catch that failure mode and move the state machine to DEAD > sooner, to make it easier to diagnose the fault in the server.

Acked-by: Laszlo Ersek <lersek(a)redhat.com&gt;