diff options
| author | Karsten Graul <kgraul@linux.ibm.com> | 2021-08-09 11:05:56 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-08-09 10:46:59 +0100 |
| commit | 8f3d65c166797746455553f4eaf74a5f89f996d4 (patch) | |
| tree | 73d7b5903a3c337a9e30102d6ebccb6989a99a2f /net/smc/smc_llc.c | |
| parent | acc68b8d2a1196c4db806947606f162dbeed2274 (diff) | |
net/smc: fix wait on already cleared link
There can be a race between the waiters for a tx work request buffer
and the link down processing that finally clears the link. Although
all waiters are woken up before the link is cleared there might be
waiters which did not yet get back control and are still waiting.
This results in an access to a cleared wait queue head.
Fix this by introducing atomic reference counting around the wait calls,
and wait with the link clear processing until all waiters have finished.
Move the work request layer related calls into smc_wr.c and set the
link state to INACTIVE before calling smcr_link_clear() in
smc_llc_srv_add_link().
Fixes: 15e1b99aadfb ("net/smc: no WR buffer wait for terminating link group")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/smc/smc_llc.c')
| -rw-r--r-- | net/smc/smc_llc.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c index 273eaf1bfe49..2e7560eba981 100644 --- a/net/smc/smc_llc.c +++ b/net/smc/smc_llc.c @@ -888,6 +888,7 @@ int smc_llc_cli_add_link(struct smc_link *link, struct smc_llc_qentry *qentry) if (!rc) goto out; out_clear_lnk: + lnk_new->state = SMC_LNK_INACTIVE; smcr_link_clear(lnk_new, false); out_reject: smc_llc_cli_add_link_reject(qentry); @@ -1184,6 +1185,7 @@ int smc_llc_srv_add_link(struct smc_link *link) goto out_err; return 0; out_err: + link_new->state = SMC_LNK_INACTIVE; smcr_link_clear(link_new, false); return rc; } @@ -1286,10 +1288,8 @@ static void smc_llc_process_cli_delete_link(struct smc_link_group *lgr) del_llc->reason = 0; smc_llc_send_message(lnk, &qentry->msg); /* response */ - if (smc_link_downing(&lnk_del->state)) { - if (smc_switch_conns(lgr, lnk_del, false)) - smc_wr_tx_wait_no_pending_sends(lnk_del); - } + if (smc_link_downing(&lnk_del->state)) + smc_switch_conns(lgr, lnk_del, false); smcr_link_clear(lnk_del, true); active_links = smc_llc_active_link_count(lgr); @@ -1805,8 +1805,6 @@ void smc_llc_link_clear(struct smc_link *link, bool log) link->smcibdev->ibdev->name, link->ibport); complete(&link->llc_testlink_resp); cancel_delayed_work_sync(&link->llc_testlink_wrk); - smc_wr_wakeup_reg_wait(link); - smc_wr_wakeup_tx_wait(link); } /* register a new rtoken at the remote peer (for all links) */ |