| Message ID | 147761388212.10087.4433175969243569236.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 52e73eb |
| Headers | show |
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c index 9630d8837ba9..4a15fa5df98b 100644 --- a/drivers/dax/pmem.c +++ b/drivers/dax/pmem.c @@ -44,7 +44,6 @@ static void dax_pmem_percpu_exit(void *data) dev_dbg(dax_pmem->dev, "%s\n", __func__); percpu_ref_exit(ref); - wait_for_completion(&dax_pmem->cmp); } static void dax_pmem_percpu_kill(void *data) @@ -54,6 +53,7 @@ static void dax_pmem_percpu_kill(void *data) dev_dbg(dax_pmem->dev, "%s\n", __func__); percpu_ref_kill(ref); + wait_for_completion(&dax_pmem->cmp); } static int dax_pmem_probe(struct device *dev)
We need to wait until the percpu_ref is released before exit. Otherwise, we sometimes lose the race and trigger this new warning that was added in v4.9 (commit a67823c1ed10 "percpu-refcount: init ->confirm_switch member properly"): WARNING: CPU: 0 PID: 3629 at lib/percpu-refcount.c:107 percpu_ref_exit+0x51/0x60 [..] Call Trace: [<ffffffff814bf093>] dump_stack+0x85/0xc2 [<ffffffff810b15db>] __warn+0xcb/0xf0 [<ffffffff810b170d>] warn_slowpath_null+0x1d/0x20 [<ffffffff814d70c1>] percpu_ref_exit+0x51/0x60 [<ffffffffa005706a>] dax_pmem_percpu_exit+0x1a/0x50 [dax_pmem] [<ffffffff81615f1f>] devm_action_release+0xf/0x20 Cc: <stable@vger.kernel.org> Fixes: ab68f2622136 ("/dev/dax, pmem: direct access to persistent memory") Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- drivers/dax/pmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)