net: hns3: fix possible mismatches resp of mailbox
Currently, the mailbox synchronous communication between VF and PF use the following fields to maintain communication: 1. Origin_mbx_msg which was combined by message code and subcode, used to match request and response. 2. Received_resp which means whether received response. There may possible mismatches of the following situation: 1. VF sends message A with code=1 subcode=1. 2. PF was blocked about 500ms when processing the message A. 3. VF will detect message A timeout because it can't get the response within 500ms. 4. VF sends message B with code=1 subcode=1 which equal message A. 5. PF processes the first message A and send the response message to VF. 6. VF will identify the response matched the message B because the code/subcode is the same. This will lead to mismatch of request and response. To fix the above bug, we use the following scheme: 1. The message sent from VF was labelled with match_id which was a unique 16-bit non-zero value. 2. The response sent from PF will label with match_id which got from the request. 3. The VF uses the match_id to match request and response message. As for PF driver, it only needs to copy the match_id from request to response. Fixes: dde1a86e ("net: hns3: Add mailbox support to PF driver") Signed-off-by: Chengwen Feng <fengchengwen@huawei.com> Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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