From: Cheng Xu chengyou@linux.alibaba.com
commit ef91271c65c12d36e4c2b61c61d4849fb6d11aa0 upstream.
The calling of siw_cm_upcall and detaching new_cep with its listen_cep should be atomistic semantics. Otherwise siw_reject may be called in a temporary state, e,g, siw_cm_upcall is called but the new_cep->listen_cep has not being cleared.
This fixes a WARN:
WARNING: CPU: 7 PID: 201 at drivers/infiniband/sw/siw/siw_cm.c:255 siw_cep_put+0x125/0x130 [siw] CPU: 2 PID: 201 Comm: kworker/u16:22 Kdump: loaded Tainted: G E 5.17.0-rc7 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: iw_cm_wq cm_work_handler [iw_cm] RIP: 0010:siw_cep_put+0x125/0x130 [siw] Call Trace: <TASK> siw_reject+0xac/0x180 [siw] iw_cm_reject+0x68/0xc0 [iw_cm] cm_work_handler+0x59d/0xe20 [iw_cm] process_one_work+0x1e2/0x3b0 worker_thread+0x50/0x3a0 ? rescuer_thread+0x390/0x390 kthread+0xe5/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 </TASK>
Fixes: 6c52fdc244b5 ("rdma/siw: connection management") Link: https://lore.kernel.org/r/d528d83466c44687f3872eadcb8c184528b2e2d4.165052655... Reported-by: Luis Chamberlain mcgrof@kernel.org Reviewed-by: Bernard Metzler bmt@zurich.ibm.com Signed-off-by: Cheng Xu chengyou@linux.alibaba.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/infiniband/sw/siw/siw_cm.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/infiniband/sw/siw/siw_cm.c +++ b/drivers/infiniband/sw/siw/siw_cm.c @@ -976,14 +976,15 @@ static void siw_accept_newconn(struct si
siw_cep_set_inuse(new_cep); rv = siw_proc_mpareq(new_cep); - siw_cep_set_free(new_cep); - if (rv != -EAGAIN) { siw_cep_put(cep); new_cep->listen_cep = NULL; - if (rv) + if (rv) { + siw_cep_set_free(new_cep); goto error; + } } + siw_cep_set_free(new_cep); } return;