This is a note to let you know that I've just added the patch titled sfc: Poll for MCDI completion once before timeout occurs to the 3.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sfc-poll-for-mcdi-completion-once-before-timeout-occurs.patch and it can be found in the queue-3.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Jan 13 09:44:41 PST 2014 From: Robert Stonehouse <rstonehouse@xxxxxxxxxxxxxx> Date: Wed, 9 Oct 2013 11:52:48 +0100 Subject: sfc: Poll for MCDI completion once before timeout occurs From: Robert Stonehouse <rstonehouse@xxxxxxxxxxxxxx> [ Upstream commit 6b294b8efedaa7cf7507154148e2c79766ad6f96 ] There is an as-yet unexplained bug that sometimes prevents (or delays) the driver seeing the completion event for a completed MCDI request on the SFC9120. The requested configuration change will have happened but the driver assumes it to have failed, and this can result in further failures. We can mitigate this by polling for completion after unsuccessfully waiting for an event. Fixes: 8127d661e77f ('sfc: Add support for Solarflare SFC9100 family') Signed-off-by: Ben Hutchings <bhutchings@xxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/sfc/mcdi.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -630,6 +630,16 @@ int efx_mcdi_rpc_finish(struct efx_nic * rc = efx_mcdi_await_completion(efx); if (rc != 0) { + netif_err(efx, hw, efx->net_dev, + "MC command 0x%x inlen %d mode %d timed out\n", + cmd, (int)inlen, mcdi->mode); + + if (mcdi->mode == MCDI_MODE_EVENTS && efx_mcdi_poll_once(efx)) { + netif_err(efx, hw, efx->net_dev, + "MCDI request was completed without an event\n"); + rc = 0; + } + /* Close the race with efx_mcdi_ev_cpl() executing just too late * and completing a request we've just cancelled, by ensuring * that the seqno check therein fails. @@ -638,11 +648,9 @@ int efx_mcdi_rpc_finish(struct efx_nic * ++mcdi->seqno; ++mcdi->credits; spin_unlock_bh(&mcdi->iface_lock); + } - netif_err(efx, hw, efx->net_dev, - "MC command 0x%x inlen %d mode %d timed out\n", - cmd, (int)inlen, mcdi->mode); - } else { + if (rc == 0) { size_t hdr_len, data_len; /* At the very least we need a memory barrier here to ensure Patches currently in stable-queue which might be from rstonehouse@xxxxxxxxxxxxxx are queue-3.12/sfc-refactor-efx_mcdi_poll-by-introducing-efx_mcdi_poll_once.patch queue-3.12/sfc-poll-for-mcdi-completion-once-before-timeout-occurs.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html