4.19-stable review patch. If anyone has any objections, please let me know.
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From: Dan Williams dan.j.williams@intel.com
commit 5d394eee2c102453278d81d9a7cf94c80253486a upstream.
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 Reviewed-by: Johannes Thumshirn jthumshirn@suse.de Reviewed-by: Dave Jiang dave.jiang@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/nvdimm/region_devs.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -560,10 +560,17 @@ static ssize_t region_badblocks_show(str 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,