On Thu, Mar 26, 2020 at 12:38:07PM -0400, Dennis Dalessandro wrote:
From: Kaike Wan kaike.wan@intel.com
When the hfi1 driver is unloaded, kmemleak will report the following issue:
unreferenced object 0xffff8888461a4c08 (size 8): comm "kworker/0:0", pid 5, jiffies 4298601264 (age 2047.134s) hex dump (first 8 bytes): 73 64 6d 61 30 00 ff ff sdma0... backtrace: [<00000000311a6ef5>] kvasprintf+0x62/0xd0 [<00000000ade94d9f>] kobject_set_name_vargs+0x1c/0x90 [<0000000060657dbb>] kobject_init_and_add+0x5d/0xb0 [<00000000346fe72b>] 0xffffffffa0c5ecba [<000000006cfc5819>] 0xffffffffa0c866b9 [<0000000031c65580>] 0xffffffffa0c38e87 [<00000000e9739b3f>] local_pci_probe+0x41/0x80 [<000000006c69911d>] work_for_cpu_fn+0x16/0x20 [<00000000601267b5>] process_one_work+0x171/0x380 [<0000000049a0eefa>] worker_thread+0x1d1/0x3f0 [<00000000909cf2b9>] kthread+0xf8/0x130 [<0000000058f5f874>] ret_from_fork+0x35/0x40
This patch fixes the issue by:
- Releasing dd->per_sdma[i].kobject in hfi1_unregister_sysfs().
- This will fix the memory leak.
- Calling kobject_put() to unwind operations only for those entries in dd->per_sdma[] whose operations have succeeded (including the current one that has just failed) in hfi1_verbs_register_sysfs().
Fixes: 0cb2aa690c7e ("IB/hfi1: Add sysfs interface for affinity setup") Cc: stable@vger.kernel.org Reviewed-by: Mike Marciniszyn mike.marciniszyn@intel.com Signed-off-by: Kaike Wan kaike.wan@intel.com Signed-off-by: Dennis Dalessandro dennis.dalessandro@intel.com
drivers/infiniband/hw/hfi1/sysfs.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
I'm not certain, but this seems unwise.
After hfi1_verbs_unregiser_sysfs() returns there should be no sysfs left under the ibdev as we are going to delete the ibdev sysfs next.
kobject_del() triggers synchronous delete of the sysfs, while kobject_put() potentially defers it to the future.
Will ib unregister fail if the kobject_del() has not happened yet? I am unsure.
Jason