000da5202e
embryonic connection has been setup and never attempt to abort a tid before this is done. This fixes a bad race where a listening socket is closed when the driver is in the middle of step (b) here. The symptom of this were "ARP miss" errors from the driver followed by tid leaks. A hardware-offloaded passive open works this way: a) A SYN "hits" the TCAM entry for a server tid and the chip delivers it to the queue associated with the server tid (say, queue A). It waits for a response from the driver telling it what to do. b) The driver decides it is ok to proceed. It adds the new tid to the list of embryonic connections associated with the server tid and then hands off the SYN to the kernel's syncache to make sure that the kernel okays it too. If it does then the driver provides an L2 table entry, queue id (say, queue B), etc. and instructs the chip to send the SYN/ACK response. c) The chip delivers a status to queue B depending on how the third step of the 3-way handshake goes. The driver removes the tid from its list of embryonic connections and either expands the syncache entry or destroys the tid. In any case all subsequent messages for the new tid will be delivered to queue B, not queue A. Anything running in queue B knows that the L2 entry has long been setup and the new flag is of no interest from here on. If the listener is closed it will deal with so_comp as normal. MFC after: 1 week |
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| .. | ||
| t4_connect.c | ||
| t4_cpl_io.c | ||
| t4_ddp.c | ||
| t4_listen.c | ||
| t4_tom_l2t.c | ||
| t4_tom_l2t.h | ||
| t4_tom.c | ||
| t4_tom.h | ||