Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756085Ab3CZWwV (ORCPT ); Tue, 26 Mar 2013 18:52:21 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:52969 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755859Ab3CZWwO (ORCPT ); Tue, 26 Mar 2013 18:52:14 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ben Hutchings Subject: [ 24/72] sfc: Avoid generating over-length MC_CMD_FLUSH_RX_QUEUES request Date: Tue, 26 Mar 2013 15:51:07 -0700 Message-Id: <20130326224922.189659140@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130326224919.675227837@linuxfoundation.org> References: <20130326224919.675227837@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2562 Lines: 75 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Hutchings [ Upstream commit 450783747f42dfa3883920acfad4acdd93ce69af ] MCDI supports requests up to 252 bytes long, which is only enough to pass 63 RX queue IDs to MC_CMD_FLUSH_RX_QUEUES. However a VF may have up to 64 RX queues, and if we try to flush them all we will generate an over-length request and BUG() in efx_mcdi_copyin(). Currently all VF drivers limit themselves to 32 RX queues, so reducing the limit to 63 does no harm. Also add a BUILD_BUG_ON in efx_mcdi_flush_rxqs() so we remember to deal with the same problem there if EFX_MAX_CHANNELS is increased. Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/sfc/mcdi.c | 3 +++ drivers/net/ethernet/sfc/siena_sriov.c | 7 +++++++ 2 files changed, 10 insertions(+) --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -1168,6 +1168,9 @@ int efx_mcdi_flush_rxqs(struct efx_nic * __le32 *qid; int rc, count; + BUILD_BUG_ON(EFX_MAX_CHANNELS > + MC_CMD_FLUSH_RX_QUEUES_IN_QID_OFST_MAXNUM); + qid = kmalloc(EFX_MAX_CHANNELS * sizeof(*qid), GFP_KERNEL); if (qid == NULL) return -ENOMEM; --- a/drivers/net/ethernet/sfc/siena_sriov.c +++ b/drivers/net/ethernet/sfc/siena_sriov.c @@ -21,6 +21,9 @@ /* Number of longs required to track all the VIs in a VF */ #define VI_MASK_LENGTH BITS_TO_LONGS(1 << EFX_VI_SCALE_MAX) +/* Maximum number of RX queues supported */ +#define VF_MAX_RX_QUEUES 63 + /** * enum efx_vf_tx_filter_mode - TX MAC filtering behaviour * @VF_TX_FILTER_OFF: Disabled @@ -578,6 +581,7 @@ static int efx_vfdi_init_rxq(struct efx_ efx_oword_t reg; if (bad_vf_index(efx, vf_evq) || bad_vf_index(efx, vf_rxq) || + vf_rxq >= VF_MAX_RX_QUEUES || bad_buf_count(buf_count, EFX_MAX_DMAQ_SIZE)) { if (net_ratelimit()) netif_err(efx, hw, efx->net_dev, @@ -683,6 +687,9 @@ static int efx_vfdi_fini_all_queues(stru __le32 *rxqs; int rc; + BUILD_BUG_ON(VF_MAX_RX_QUEUES > + MC_CMD_FLUSH_RX_QUEUES_IN_QID_OFST_MAXNUM); + rxqs = kmalloc(count * sizeof(*rxqs), GFP_KERNEL); if (rxqs == NULL) return VFDI_RC_ENOMEM; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/