libnvdimm/security: Require nvdimm_security_setup_events() to succeed
authorDan Williams <dan.j.williams@intel.com>
Sat, 19 Jan 2019 16:45:56 +0000 (08:45 -0800)
committerDan Williams <dan.j.williams@intel.com>
Mon, 21 Jan 2019 17:57:43 +0000 (09:57 -0800)
commit1cd7386549f9b6f2f230da54aa9e7fe2d6c216d2
tree527eed888a48757834f6a672cbb034a1bb67e547
parent266c7bf52a7fe5cb5a97e78fedcaac629378008f
libnvdimm/security: Require nvdimm_security_setup_events() to succeed

The following warning:

    ACPI0012:00: security event setup failed: -19

...is meant to capture exceptional failures of sysfs_get_dirent(),
however it will also fail in the common case when security support is
disabled. A few issues:

1/ A dev_warn() report for a common case is too chatty
2/ The setup of this notifier is generic, no need for it to be driven
   from the nfit driver, it can exist completely in the core.
3/ If it fails for any reason besides security support being disabled,
   that's fatal and should abort DIMM activation. Userspace may hang if
   it never gets overwrite notifications.
4/ The dirent needs to be released.

Move the call to the core 'dimm' driver, make it conditional on security
support being active, make it fatal for the exceptional case, add the
missing sysfs_put() at device disable time.

Fixes: 7d988097c546 ("...Add security DSM overwrite support")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/acpi/nfit/core.c
drivers/nvdimm/dimm.c
drivers/nvdimm/dimm_devs.c
drivers/nvdimm/nd.h
include/linux/libnvdimm.h