On 09/28/2018 11:04 AM, Dan Williams wrote:

While experimenting with region driver loading the following backtrace was triggered:

INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. [..] Call Trace: dump_stack+0x85/0xcb register_lock_class+0x571/0x580 ? __lock_acquire+0x2ba/0x1310 ? kernfs_seq_start+0x2a/0x80 __lock_acquire+0xd4/0x1310 ? dev_attr_show+0x1c/0x50 ? __lock_acquire+0x2ba/0x1310 ? kernfs_seq_start+0x2a/0x80 ? lock_acquire+0x9e/0x1a0 lock_acquire+0x9e/0x1a0 ? dev_attr_show+0x1c/0x50 badblocks_show+0x70/0x190 ? dev_attr_show+0x1c/0x50 dev_attr_show+0x1c/0x50

This results from a missing successful call to devm_init_badblocks() from nd_region_probe(). Block attempts to show badblocks while the region is not enabled.

Fixes: 6a6bef90425e ("libnvdimm: add mechanism to publish badblocks...") Cc: stable@vger.kernel.org Cc: Dave Jiang dave.jiang@intel.com Cc: Johannes Thumshirn jthumshirn@suse.de Signed-off-by: Dan Williams dan.j.williams@intel.com

Reviewed-by: Dave Jiang dave.jiang@intel.com

---

drivers/nvdimm/region_devs.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index fa37afcd43ff..174a418cb171 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -560,10 +560,17 @@ static ssize_t region_badblocks_show(struct device *dev, struct device_attribute *attr, char *buf) { struct nd_region *nd_region = to_nd_region(dev);

• ssize_t rc;

• return badblocks_show(&nd_region->bb, buf, 0);

-}

• device_lock(dev);
• if (dev->driver)

• rc = badblocks_show(&nd_region->bb, buf, 0);
  

• else

• rc = -ENXIO;
  

• device_unlock(dev);

• return rc;

+} static DEVICE_ATTR(badblocks, 0444, region_badblocks_show, NULL); static ssize_t resource_show(struct device *dev,