On Mon, Sep 6, 2021 at 7:32 PM Jesper Dangaard Brouer <jbrouer@xxxxxxxxxx> wrote: > > Hi Feng and Jason, > > Please notice that you are both developing patches that change the ixgbe > driver in related areas. Thanks for noticing. We're doing different things as they are both related to XDP on ixgbe actually. Jason > > Jason's patch: > Subject: [PATCH v7] ixgbe: let the xdpdrv work with more than 64 cpus > > https://lore.kernel.org/all/20210901101206.50274-1-kerneljasonxing@xxxxxxxxx/ > > We might need both as this patch looks like a fix to a panic, and > Jason's patch allows XDP on ixgbe to work on machines with more than 64 > CPUs. > > -Jesper > > On 06/09/2021 09.49, Feng Zhou wrote: > > > > 在 2021/9/6 下午2:37, Paul Menzel 写道: > >> Dear Feng, > >> > >> > >> Am 03.09.21 um 08:40 schrieb Feng zhou: > >> > >> (If you care, in your email client, your last name does not start with > >> a capital letter.) > >> > >>> From: Feng Zhou <zhoufeng.zf@xxxxxxxxxxxxx> > >>> > >>> The ixgbe driver currently generates a NULL pointer dereference with > >>> some machine (online cpus < 63). This is due to the fact that the > >>> maximum value of num_xdp_queues is nr_cpu_ids. Code is in > >>> "ixgbe_set_rss_queues"". > >>> > >>> Here's how the problem repeats itself: > >>> Some machine (online cpus < 63), And user set num_queues to 63 through > >>> ethtool. Code is in the "ixgbe_set_channels", > >>> adapter->ring_feature[RING_F_FDIR].limit = count; > >> > >> For better legibility, you might want to indent code (blocks) by four > >> spaces and add blank lines around it (also below). > >> > >>> It becames 63. > >> > >> becomes > >> > >>> When user use xdp, "ixgbe_set_rss_queues" will set queues num. > >>> adapter->num_rx_queues = rss_i; > >>> adapter->num_tx_queues = rss_i; > >>> adapter->num_xdp_queues = ixgbe_xdp_queues(adapter); > >>> And rss_i's value is from > >>> f = &adapter->ring_feature[RING_F_FDIR]; > >>> rss_i = f->indices = f->limit; > >>> So "num_rx_queues" > "num_xdp_queues", when run to "ixgbe_xdp_setup", > >>> for (i = 0; i < adapter->num_rx_queues; i++) > >>> if (adapter->xdp_ring[i]->xsk_umem) > >>> lead to panic. > >> > >> lead*s*? > >> > >>> Call trace: > >>> [exception RIP: ixgbe_xdp+368] > >>> RIP: ffffffffc02a76a0 RSP: ffff9fe16202f8d0 RFLAGS: 00010297 > >>> RAX: 0000000000000000 RBX: 0000000000000020 RCX: 0000000000000000 > >>> RDX: 0000000000000000 RSI: 000000000000001c RDI: ffffffffa94ead90 > >>> RBP: ffff92f8f24c0c18 R8: 0000000000000000 R9: 0000000000000000 > >>> R10: ffff9fe16202f830 R11: 0000000000000000 R12: ffff92f8f24c0000 > >>> R13: ffff9fe16202fc01 R14: 000000000000000a R15: ffffffffc02a7530 > >>> ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 > >>> 7 [ffff9fe16202f8f0] dev_xdp_install at ffffffffa89fbbcc > >>> 8 [ffff9fe16202f920] dev_change_xdp_fd at ffffffffa8a08808 > >>> 9 [ffff9fe16202f960] do_setlink at ffffffffa8a20235 > >>> 10 [ffff9fe16202fa88] rtnl_setlink at ffffffffa8a20384 > >>> 11 [ffff9fe16202fc78] rtnetlink_rcv_msg at ffffffffa8a1a8dd > >>> 12 [ffff9fe16202fcf0] netlink_rcv_skb at ffffffffa8a717eb > >>> 13 [ffff9fe16202fd40] netlink_unicast at ffffffffa8a70f88 > >>> 14 [ffff9fe16202fd80] netlink_sendmsg at ffffffffa8a71319 > >>> 15 [ffff9fe16202fdf0] sock_sendmsg at ffffffffa89df290 > >>> 16 [ffff9fe16202fe08] __sys_sendto at ffffffffa89e19c8 > >>> 17 [ffff9fe16202ff30] __x64_sys_sendto at ffffffffa89e1a64 > >>> 18 [ffff9fe16202ff38] do_syscall_64 at ffffffffa84042b9 > >>> 19 [ffff9fe16202ff50] entry_SYSCALL_64_after_hwframe at ffffffffa8c0008c > >> > >> Please describe the fix in the commit message. > >> > >>> Fixes: 4a9b32f30f80 ("ixgbe: fix potential RX buffer starvation for > >>> AF_XDP") > >>> Signed-off-by: Feng Zhou <zhoufeng.zf@xxxxxxxxxxxxx> > >>> --- > >>> Updates since v1: > >>> - Fix "ixgbe_max_channels" callback so that it will not allow a > >>> setting of > >>> queues to be higher than the num_online_cpus(). > >>> more details can be seen from here: > >>> https://patchwork.ozlabs.org/project/intel-wired-lan/patch/20210817075407.11961-1-zhoufeng.zf@xxxxxxxxxxxxx/ > >>> > >>> Thanks to Maciej Fijalkowski for your advice. > >>> > >>> drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c | 2 +- > >>> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 8 ++++++-- > >>> 2 files changed, 7 insertions(+), 3 deletions(-) > >>> > >>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c > >>> b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c > >>> index 4ceaca0f6ce3..21321d164708 100644 > >>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c > >>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c > >>> @@ -3204,7 +3204,7 @@ static unsigned int ixgbe_max_channels(struct > >>> ixgbe_adapter *adapter) > >>> max_combined = ixgbe_max_rss_indices(adapter); > >>> } > >>> - return max_combined; > >>> + return min_t(int, max_combined, num_online_cpus()); > >>> } > >>> static void ixgbe_get_channels(struct net_device *dev, > >>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > >>> b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > >>> index 14aea40da50f..5db496cc5070 100644 > >>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > >>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > >>> @@ -10112,6 +10112,7 @@ static int ixgbe_xdp_setup(struct net_device > >>> *dev, struct bpf_prog *prog) > >>> struct ixgbe_adapter *adapter = netdev_priv(dev); > >>> struct bpf_prog *old_prog; > >>> bool need_reset; > >>> + int num_queues; > >>> if (adapter->flags & IXGBE_FLAG_SRIOV_ENABLED) > >>> return -EINVAL; > >>> @@ -10161,11 +10162,14 @@ static int ixgbe_xdp_setup(struct > >>> net_device *dev, struct bpf_prog *prog) > >>> /* Kick start the NAPI context if there is an AF_XDP socket open > >>> * on that queue id. This so that receiving will start. > >>> */ > >>> - if (need_reset && prog) > >>> - for (i = 0; i < adapter->num_rx_queues; i++) > >>> + if (need_reset && prog) { > >>> + num_queues = min_t(int, adapter->num_rx_queues, > >>> + adapter->num_xdp_queues); > >>> + for (i = 0; i < num_queues; i++) > >>> if (adapter->xdp_ring[i]->xsk_pool) > >>> (void)ixgbe_xsk_wakeup(adapter->netdev, i, > >>> XDP_WAKEUP_RX); > >>> + } > >>> return 0; > >>> } > >>> > > Thanks for your advice. I will modify the commit message in v3 > > >
