net/tap: fix unexpected link handler
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Commit Message
From: Yunjian Wang <wangyunjian@huawei.com>
The nic's interrupt source has some active handler, which maybe call
tap_dev_intr_handler() to set link handler. We should cancel the link
handler before close fd to prevent executing the link handler. It
triggers segfault.
Call Trace:
0x00007f15e08dad99 in __rte_panic (Error adding fd %d epoll_ctl, %s\n")
0x00007f15e08e9b87 in eal_intr_thread_main ()
0x00007f15e249be15 in start_thread ()
0x00007f15d5322f9d in clone ()
Fixes: c0bddd3a057f ("net/tap: add link status notification")
CC: stable@dpdk.org
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
---
drivers/net/tap/rte_eth_tap.c | 27 ++++++++++++++++++++++-----
1 file changed, 22 insertions(+), 5 deletions(-)
Comments
On 4/16/2020 2:50 PM, wangyunjian wrote:
> From: Yunjian Wang <wangyunjian@huawei.com>
>
> The nic's interrupt source has some active handler, which maybe call
> tap_dev_intr_handler() to set link handler. We should cancel the link
> handler before close fd to prevent executing the link handler. It
> triggers segfault.
>
> Call Trace:
> 0x00007f15e08dad99 in __rte_panic (Error adding fd %d epoll_ctl, %s\n")
> 0x00007f15e08e9b87 in eal_intr_thread_main ()
> 0x00007f15e249be15 in start_thread ()
> 0x00007f15d5322f9d in clone ()
>
> Fixes: c0bddd3a057f ("net/tap: add link status notification")
> CC: stable@dpdk.org
>
> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
Applied to dpdk-next-net/master, thanks.
@@ -18,6 +18,7 @@
#include <rte_string_fns.h>
#include <rte_ethdev.h>
#include <rte_errno.h>
+#include <rte_cycles.h>
#include <assert.h>
#include <sys/types.h>
@@ -1563,13 +1564,12 @@ static int
tap_lsc_intr_handle_set(struct rte_eth_dev *dev, int set)
{
struct pmd_internals *pmd = dev->data->dev_private;
+ int ret;
/* In any case, disable interrupt if the conf is no longer there. */
if (!dev->data->dev_conf.intr_conf.lsc) {
if (pmd->intr_handle.fd != -1) {
- tap_nl_final(pmd->intr_handle.fd);
- rte_intr_callback_unregister(&pmd->intr_handle,
- tap_dev_intr_handler, dev);
+ goto clean;
}
return 0;
}
@@ -1580,9 +1580,26 @@ tap_lsc_intr_handle_set(struct rte_eth_dev *dev, int set)
return rte_intr_callback_register(
&pmd->intr_handle, tap_dev_intr_handler, dev);
}
+
+clean:
+ do {
+ ret = rte_intr_callback_unregister(&pmd->intr_handle,
+ tap_dev_intr_handler, dev);
+ if (ret >= 0) {
+ break;
+ } else if (ret == -EAGAIN) {
+ rte_delay_ms(100);
+ } else {
+ TAP_LOG(ERR, "intr callback unregister failed: %d",
+ ret);
+ break;
+ }
+ } while (true);
+
tap_nl_final(pmd->intr_handle.fd);
- return rte_intr_callback_unregister(&pmd->intr_handle,
- tap_dev_intr_handler, dev);
+ pmd->intr_handle.fd = -1;
+
+ return 0;
}
static int