Searched hist:d08cd5e0eb632eef7819ba911c09d89a767f2d0c (Results 1 – 1 of 1) sorted by relevance
| /openbmc/linux/drivers/nvdimm/ |
| H A D | btt.c | diff d08cd5e0eb632eef7819ba911c09d89a767f2d0c Wed Dec 13 15:33:09 CST 2017 Jeff Moyer <jmoyer@redhat.com> libnvdimm, btt: fix uninitialized err_lock
When a sector mode namespace is initially created, the arena's err_lock
is not initialized. If, on the other hand, the namespace already
exists, the mutex is initialized. To fix the issue, I moved the mutex
initialization into the arena_alloc, which is called by both
discover_arenas and create_arenas.
This was discovered on an older kernel where mutex_trylock checks the
count to determine whether the lock is held. Because the data structure
is kzalloc-d, that count was 0 (held), and I/O to the device would hang
forever waiting for the lock to be released (see btt_write_pg, for
example). Current kernels have a different mutex implementation that
checks for a non-null owner, and so this doesn't show up as a problem.
If that lock were ever contended, it might cause issues, but you'd have
to be really unlucky, I think.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
|