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| author | Li Zhong <lizhongfs@gmail.com> | 2019-08-05 08:43:36 +0800 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2019-08-07 21:52:01 -0400 |
| commit | 7d8948627a7cd84c45069276e5fcddf6ab074baa (patch) | |
| tree | 0dce2daf349a3dd03eb3a4b8e0036ba0e89c57bd /drivers/target | |
| parent | cb8b3359eb9c606421a42f3968c12211d6462906 (diff) | |
| download | linux-7d8948627a7cd84c45069276e5fcddf6ab074baa.tar.bz2 | |
scsi: target: tcmu: clean the nl_cmd of the udev when nl send fails
If the userspace process crashes while we send the nl msg, it is possible
that the cmd in curr_nl_cmd of tcmu_dev never gets reset to 0, and and
returns busy for other commands after the userspace process is restartd.
More details below:
/backstores/user:file/file> set attribute dev_size=2048
Cannot set attribute dev_size: [Errno 3] No such process
/backstores/user:file/file> set attribute dev_size=2048
Cannot set attribute dev_size: [Errno 16] Device or resource busy
with following kernel messages:
[173605.747169] Unable to reconfigure device
[173616.686674] tcmu daemon: command reply support 1.
[173623.866978] netlink cmd 3 already executing on file
[173623.866984] Unable to reconfigure device
Also, it is not safe to leave the nl_cmd in the list, and not get deleted.
This patch removes the nl_cmd from the list, and clear its data if it is
not sent successfully.
Signed-off-by: Li Zhong <lizhongfs@gmail.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/target')
| -rw-r--r-- | drivers/target/target_core_user.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 04eda111920e..68045cbca595 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1708,6 +1708,24 @@ static int tcmu_init_genl_cmd_reply(struct tcmu_dev *udev, int cmd) return 0; } +static void tcmu_destroy_genl_cmd_reply(struct tcmu_dev *udev) +{ + struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; + + if (!tcmu_kern_cmd_reply_supported) + return; + + if (udev->nl_reply_supported <= 0) + return; + + mutex_lock(&tcmu_nl_cmd_mutex); + + list_del(&nl_cmd->nl_list); + memset(nl_cmd, 0, sizeof(*nl_cmd)); + + mutex_unlock(&tcmu_nl_cmd_mutex); +} + static int tcmu_wait_genl_cmd_reply(struct tcmu_dev *udev) { struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; @@ -1788,6 +1806,8 @@ static int tcmu_netlink_event_send(struct tcmu_dev *udev, if (ret == 0 || (ret == -ESRCH && cmd == TCMU_CMD_ADDED_DEVICE)) return tcmu_wait_genl_cmd_reply(udev); + else + tcmu_destroy_genl_cmd_reply(udev); return ret; } |