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Cisco Bug: CSCvi66823 - Direct Descriptor Feature doesnt work in Bodega

Last Modified

Oct 22, 2018

Products (1)

  • Cisco UCS Virtual Interface Card

Known Affected Releases


Description (partial)

1. CQ Entries for direct descriptor packets are misdelivered to other active CQ's on system if no_cq bit is not set
2. CQ entries for completions of other RQs in the system are missing if no_cq bit is set.

Load RW rule which converts payload of UDP packet into Direct descriptor packet (example below used ?no_cq? bit).  Add a classifier entry that sends UDP packets on port 4444 to this rule.  Start a separate receiver to sink UDP port 3333 packets.  Start a stream of port 3333 packets. Start a stream of port 4444 packets.  The ?sink? program will immediately stop reporting receipt of port 3333 packets due to missing CQ entries.  We can see that the packets have been delivered to the port 3333 RQ has run out of posted buffers because there have been no completions delivered to trigger buffer restocking.

RW rule used for testing is:
00000000: 90b5a001             li r1, 0xb5a0    // host vaddr = 0x63b5a0
00000004: 3d006311             orsi r1, r1, 0x63, 16

00000008: 403fcb22             lh r2, -62(meta) // packet size
0000000c: 03600a22             sub r2, r2, L5   // remove header length

00000010: 70720beb             sfi 11, 32-0x100(meta),7,4    // OPCODE = 11

00000014: 08c00a00             delm 0(L5)       // remove header
00000018: 07200381             ins r1, 0, 8            // insert VADDR
0000001c: 2e000f12             bfinsi r2, 15, 1, 1     // set no_cq
00000020: 07200182             ins r2, 0, 4            // length
00000024: 07000003             insz 4           // 4 zeros per TOO

00000028: 07800019             end       // send payload and exit
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