> -----Original Message----- > From: Christophe JAILLET <[email protected]> > Sent: Thursday, August 22, 2024 1:34 AM > To: Haiyang Zhang <[email protected]> > Cc: [email protected]; [email protected]; [email protected]; > [email protected]; Dexuan Cui <[email protected]>; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected]; KY Srinivasan > <[email protected]>; [email protected]; [email protected]; linux- > [email protected]; [email protected]; Long Li > <[email protected]>; [email protected]; [email protected]; > [email protected]; Paul Rosswurm <[email protected]>; > [email protected]; [email protected]; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > Subject: Re: [PATCH net] net: mana: Fix race of mana_hwc_post_rx_wqe and > new hwc response > > Le 21/08/2024 à 22:42, Haiyang Zhang a écrit : > > The mana_hwc_rx_event_handler() / mana_hwc_handle_resp() calls > > complete(&ctx->comp_event) before posting the wqe back. It's > > possible that other callers, like mana_create_txq(), start the > > next round of mana_hwc_send_request() before the posting of wqe. > > And if the HW is fast enough to respond, it can hit no_wqe error > > on the HW channel, then the response message is lost. The mana > > driver may fail to create queues and open, because of waiting for > > the HW response and timed out. > > Sample dmesg: > > [ 528.610840] mana 39d4:00:02.0: HWC: Request timed out! > > [ 528.614452] mana 39d4:00:02.0: Failed to send mana message: -110, 0x0 > > [ 528.618326] mana 39d4:00:02.0 enP14804s2: Failed to create WQ object: > -110 > > > > To fix it, move posting of rx wqe before complete(&ctx->comp_event). > > > > Cc: [email protected] > > Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure > Network Adapter (MANA)") > > Signed-off-by: Haiyang Zhang <haiyangz- > [email protected]> > > --- > > .../net/ethernet/microsoft/mana/hw_channel.c | 62 ++++++++++--------- > > 1 file changed, 34 insertions(+), 28 deletions(-) > > > > diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c > b/drivers/net/ethernet/microsoft/mana/hw_channel.c > > index cafded2f9382..a00f915c5188 100644 > > --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c > > +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c > > @@ -52,9 +52,33 @@ static int mana_hwc_verify_resp_msg(const struct > hwc_caller_ctx *caller_ctx, > > return 0; > > } > > > > +static int mana_hwc_post_rx_wqe(const struct hwc_wq *hwc_rxq, > > + struct hwc_work_request *req) > > +{ > > + struct device *dev = hwc_rxq->hwc->dev; > > + struct gdma_sge *sge; > > + int err; > > + > > + sge = &req->sge; > > + sge->address = (u64)req->buf_sge_addr; > > + sge->mem_key = hwc_rxq->msg_buf->gpa_mkey; > > + sge->size = req->buf_len; > > + > > + memset(&req->wqe_req, 0, sizeof(struct gdma_wqe_request)); > > + req->wqe_req.sgl = sge; > > + req->wqe_req.num_sge = 1; > > + req->wqe_req.client_data_unit = 0; > > Hi, > > unrelated to your patch, but this initialization is useless, it is > already memset(0)'ed a few lines above. > So why client_data_unit and not some other fields?
Agreed. This patch just moves the function for the bug fix. We will do code cleanups in other patches. Thanks, - Haiyang
