On 02.10.24 16:49, Markus Armbruster wrote:
Eric Blake <ebl...@redhat.com> writes:Although defaulting the handshake limit to 10 seconds was a nice QoI change to weed out intentionally slow clients, it can interfere with integration testing done with manual NBD_OPT commands over 'nbdsh --opt-mode'. Expose a QMP knob 'handshake-max-secs' to allow the user to alter the timeout away from the default. The parameter name here intentionally matches the spelling of the constant added in commit fb1c2aaa98, and not the command-line spelling added in the previous patch for qemu-nbd; that's because in QMP, longer names serve as good self-documentation, and unlike the command line, machines don't have problems generating longer spellings. Signed-off-by: Eric Blake <ebl...@redhat.com> --- qapi/block-export.json | 10 ++++++++++ include/block/nbd.h | 6 +++--- block/monitor/block-hmp-cmds.c | 4 ++-- blockdev-nbd.c | 26 ++++++++++++++++++-------- 4 files changed, 33 insertions(+), 13 deletions(-) diff --git a/qapi/block-export.json b/qapi/block-export.json index ce33fe378df..c110dd375ad 100644 --- a/qapi/block-export.json +++ b/qapi/block-export.json @@ -17,6 +17,10 @@ # # @addr: Address on which to listen. # +# @handshake-max-secs: Time limit, in seconds, at which a client that +# has not completed the negotiation handshake will be disconnected, +# or 0 for no limit (since 9.2; default: 10). +# # @tls-creds: ID of the TLS credentials object (since 2.6). # # @tls-authz: ID of the QAuthZ authorization object used to validate @@ -34,6 +38,7 @@ ## { 'struct': 'NbdServerOptions', 'data': { 'addr': 'SocketAddress', + '*handshake-max-secs': 'uint32', '*tls-creds': 'str', '*tls-authz': 'str', '*max-connections': 'uint32' } } @@ -52,6 +57,10 @@ # # @addr: Address on which to listen. # +# @handshake-max-secs: Time limit, in seconds, at which a client that +# has not completed the negotiation handshake will be disconnected, +# or 0 for no limit (since 9.2; default: 10). +# # @tls-creds: ID of the TLS credentials object (since 2.6). # # @tls-authz: ID of the QAuthZ authorization object used to validate @@ -72,6 +81,7 @@ ## { 'command': 'nbd-server-start', 'data': { 'addr': 'SocketAddressLegacy', + '*handshake-max-secs': 'uint32', '*tls-creds': 'str', '*tls-authz': 'str', '*max-connections': 'uint32' },Are we confident we'll never need less than a full second?
Hmm, recent "[PATCH v2] chardev: introduce 'reconnect-ms' and deprecate 'reconnect'" shows that at least sometimes second is not enough precision. Maybe, using milliseconds consistently for all relatively short time intervals in QAPI would be a good rule? -- Best regards, Vladimir
