From: Kaike Wan <kaike.wan@xxxxxxxxx> commit 5c15abc4328ad696fa61e2f3604918ed0c207755 upstream. 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(). Cc: <stable@xxxxxxxxxxxxxxx> Fixes: 0cb2aa690c7e ("IB/hfi1: Add sysfs interface for affinity setup") Link: https://lore.kernel.org/r/20200326163807.21129.27371.stgit@xxxxxxxxxxxxxxxxxxxx Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx> Signed-off-by: Kaike Wan <kaike.wan@xxxxxxxxx> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/hfi1/sysfs.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) --- a/drivers/infiniband/hw/hfi1/sysfs.c +++ b/drivers/infiniband/hw/hfi1/sysfs.c @@ -861,8 +861,13 @@ bail: for (i = 0; i < ARRAY_SIZE(hfi1_attributes); ++i) device_remove_file(&dev->dev, hfi1_attributes[i]); - for (i = 0; i < dd->num_sdma; i++) - kobject_del(&dd->per_sdma[i].kobj); + /* + * The function kobject_put() will call kobject_del() if the kobject + * has been added successfully. The sysfs files created under the + * kobject directory will also be removed during the process. + */ + for (; i >= 0; i--) + kobject_put(&dd->per_sdma[i].kobj); return ret; } @@ -875,6 +880,10 @@ void hfi1_verbs_unregister_sysfs(struct struct hfi1_pportdata *ppd; int i; + /* Unwind operations in hfi1_verbs_register_sysfs() */ + for (i = 0; i < dd->num_sdma; i++) + kobject_put(&dd->per_sdma[i].kobj); + for (i = 0; i < dd->num_pports; i++) { ppd = &dd->pport[i];