leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

net/smc: protect smc ib device initialization

Browse Source 
Before an smc ib device is used the first time for an smc link it is
lazily initialized. When there are 2 active link groups and a new ib
device is brought online then it might happen that 2 link creations run
in parallel and enter smc_ib_setup_per_ibdev(). Both allocate new send
and receive completion queues on the device, but only one set of them
keeps assigned and the other leaks.
Fix that by protecting the setup and cleanup code using a mutex.

Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: f3c1deddb2 ("net/smc: separate function for link initialization")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Karsten Graul 2020-07-18 15:06:12 +02:00 committed by David S. Miller
parent 7df8bcb560
commit 63673597cc
2 changed files with 14 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
net/smc/smc_ib.c
View File

@ -506,6 +506,10 @@ long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev)
int cqe_size_order, smc_order;
long rc;
mutex_lock(&smcibdev->mutex);
rc = 0;
if (smcibdev->initialized)
goto out;
/* the calculated number of cq entries fits to mlx5 cq allocation */
cqe_size_order = cache_line_size() == 128 ? 7 : 6;
smc_order = MAX_ORDER - cqe_size_order - 1;
@ -517,7 +521,7 @@ long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev)
rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_send);
if (IS_ERR(smcibdev->roce_cq_send)) {
smcibdev->roce_cq_send = NULL;
return rc;
goto out;
}
smcibdev->roce_cq_recv = ib_create_cq(smcibdev->ibdev,
smc_wr_rx_cq_handler, NULL,
@ -529,21 +533,26 @@ long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev)
}
smc_wr_add_dev(smcibdev);
smcibdev->initialized = 1;
return rc;
goto out;
err:
ib_destroy_cq(smcibdev->roce_cq_send);
out:
mutex_unlock(&smcibdev->mutex);
return rc;
}
static void smc_ib_cleanup_per_ibdev(struct smc_ib_device *smcibdev)
{
mutex_lock(&smcibdev->mutex);
if (!smcibdev->initialized)
return;
goto out;
smcibdev->initialized = 0;
ib_destroy_cq(smcibdev->roce_cq_recv);
ib_destroy_cq(smcibdev->roce_cq_send);
smc_wr_remove_dev(smcibdev);
out:
mutex_unlock(&smcibdev->mutex);
}
static struct ib_client smc_ib_client;
@ -566,6 +575,7 @@ static int smc_ib_add_dev(struct ib_device *ibdev)
INIT_WORK(&smcibdev->port_event_work, smc_ib_port_event_work);
atomic_set(&smcibdev->lnk_cnt, 0);
init_waitqueue_head(&smcibdev->lnks_deleted);
mutex_init(&smcibdev->mutex);
mutex_lock(&smc_ib_devices.mutex);
list_add_tail(&smcibdev->list, &smc_ib_devices.list);
mutex_unlock(&smc_ib_devices.mutex);

1
net/smc/smc_ib.h
View File

@ -52,6 +52,7 @@ struct smc_ib_device { /* ib-device infos for smc */
DECLARE_BITMAP(ports_going_away, SMC_MAX_PORTS);
atomic_t lnk_cnt; /* number of links on ibdev */
wait_queue_head_t lnks_deleted; /* wait 4 removal of all links*/
struct mutex mutex; /* protect dev setup+cleanup */
};
struct smc_buf_desc;