IB/mthca: Don't cancel commands on a signal
We have run into the following problem: if a task receives a signal
while in the process of e.g. destroying a resource (which could be
because the relevant file was closed) mthca could bail out from trying
to take a command interface semaphore without performing the
appropriate command to tell hardware that the resource is being
destroyed.
As a result we see messages like
ib_mthca 0000:04:00.0: HW2SW_CQ failed (-4)
In this case, hardware could access the resource after the memory has
been freed, possibly causing memory corruption.
A simple solution is to replace down_interruptible() by down() in
command interface activation.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
[ It's also not safe to bail out on multicast table operations, since
they may be invoked on the cleanup path too. So use down() for
mcg_table.sem too. ]
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_mcg.c b/drivers/infiniband/hw/mthca/mthca_mcg.c
index 77bc6c7..55ff5e5 100644
--- a/drivers/infiniband/hw/mthca/mthca_mcg.c
+++ b/drivers/infiniband/hw/mthca/mthca_mcg.c
@@ -154,10 +154,7 @@
return PTR_ERR(mailbox);
mgm = mailbox->buf;
- if (down_interruptible(&dev->mcg_table.sem)) {
- err = -EINTR;
- goto err_sem;
- }
+ down(&dev->mcg_table.sem);
err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
if (err)
@@ -242,7 +239,7 @@
mthca_free(&dev->mcg_table.alloc, index);
}
up(&dev->mcg_table.sem);
- err_sem:
+
mthca_free_mailbox(dev, mailbox);
return err;
}
@@ -263,10 +260,7 @@
return PTR_ERR(mailbox);
mgm = mailbox->buf;
- if (down_interruptible(&dev->mcg_table.sem)) {
- err = -EINTR;
- goto err_sem;
- }
+ down(&dev->mcg_table.sem);
err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
if (err)
@@ -372,7 +366,7 @@
out:
up(&dev->mcg_table.sem);
- err_sem:
+
mthca_free_mailbox(dev, mailbox);
return err;
}