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Description of problem:

We hit this crash when adding/deleting devices:

https://lkml.org/lkml/2015/3/11/514

The problem is that target_core_user calls tcmu_free_device -> tcmu_netlink_event (TCMU_CMD_REMOVED_DEVICE) -> uio_unregister_device. It does not wait for the TCMU_CMD_REMOVED_DEVICE userspace handler to close the uio device, so if the uio_unregister_device is faster than userspace we will hit the uio_release crash because the uio_device will be freed.


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:


Additional info:

Patch(es) committed on kernel repository and an interim kernel build is undergoing testing

Patch(es) available on kernel-3.10.0-690.el7

Regression tests on RHEL-7.4-20170630.1 w/ kernel-3.10.0-691.el7 have not found any new issue. Moving to VERIFIED as per comment#11

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2017:1842