From: Jane Chu jane.chu@oracle.com
[ Upstream commit 7f674025d9f7321dea11b802cc0ab3f09cbe51c5 ]
commit 7d988097c546 ("acpi/nfit, libnvdimm/security: Add security DSM overwrite support") adds a sysfs_notify_dirent() to wake up userspace poll thread when the "overwrite" operation has completed. But the notification is issued before the internal dimm security state and flags have been updated, so the userspace poll thread wakes up and fetches the not-yet-updated attr and falls back to sleep, forever. But if user from another terminal issue "ndctl wait-overwrite nmemX" again, the command returns instantly.
Link: https://lore.kernel.org/r/1596494499-9852-3-git-send-email-jane.chu@oracle.c... Fixes: 7d988097c546 ("acpi/nfit, libnvdimm/security: Add security DSM overwrite support") Cc: Dave Jiang dave.jiang@intel.com Cc: Dan Williams dan.j.williams@intel.com Reviewed-by: Dave Jiang dave.jiang@intel.com Signed-off-by: Jane Chu jane.chu@oracle.com Signed-off-by: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvdimm/security.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c index acfd211c01b9c..35d265014e1ec 100644 --- a/drivers/nvdimm/security.c +++ b/drivers/nvdimm/security.c @@ -450,14 +450,19 @@ void __nvdimm_security_overwrite_query(struct nvdimm *nvdimm) else dev_dbg(&nvdimm->dev, "overwrite completed\n");
- if (nvdimm->sec.overwrite_state) - sysfs_notify_dirent(nvdimm->sec.overwrite_state); + /* + * Mark the overwrite work done and update dimm security flags, + * then send a sysfs event notification to wake up userspace + * poll threads to picked up the changed state. + */ nvdimm->sec.overwrite_tmo = 0; clear_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags); clear_bit(NDD_WORK_PENDING, &nvdimm->flags); - put_device(&nvdimm->dev); nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER); nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER); + if (nvdimm->sec.overwrite_state) + sysfs_notify_dirent(nvdimm->sec.overwrite_state); + put_device(&nvdimm->dev); }
void nvdimm_security_overwrite_query(struct work_struct *work)