Date: Thu, 30 Jul 2026 05:11:12 +0000 From: Kevin Bowling <kbowling@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: e8f3b96ba794 - main - igb: Rate-limit VF VLAN rebuild requests Message-ID: <6a6adcf0.3337e.7f35a7b2@gitrepo.freebsd.org>
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The branch main has been updated by kbowling: URL: https://cgit.FreeBSD.org/src/commit/?id=e8f3b96ba794521af9904a451da33cf119381da8 commit e8f3b96ba794521af9904a451da33cf119381da8 Author: Kevin Bowling <kbowling@FreeBSD.org> AuthorDate: 2026-07-29 08:04:40 +0000 Commit: Kevin Bowling <kbowling@FreeBSD.org> CommitDate: 2026-07-30 05:10:00 +0000 igb: Rate-limit VF VLAN rebuild requests Give each VF a burst of 64 VLAN additions and refill it at eight additions per second. Removals remain unrestricted, idempotent requests consume nothing, and trusted PF-wide initialization replenishes the burst while guest resets do not. Checks VLVF capacity before charging a token. Do not apply this policy to multicast requests because Linux igbvf and DPDK ignore their reply status; aggregate MTA write elision bounds those updates instead. Sponsored by: BBOX.io --- sys/dev/e1000/if_igb_iov.c | 62 ++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 57 insertions(+), 5 deletions(-) diff --git a/sys/dev/e1000/if_igb_iov.c b/sys/dev/e1000/if_igb_iov.c index 9b2c77a92eb7..f43e994c0440 100644 --- a/sys/dev/e1000/if_igb_iov.c +++ b/sys/dev/e1000/if_igb_iov.c @@ -19,6 +19,9 @@ #define IGB_IOV_MAX_MAC_FILTERS 3 #define IGB_IOV_MAX_MC_HASHES 30 #define IGB_IOV_MBX_RETRY_COUNT 6 +/* Allow two complete 31-VID replays, then sustain eight additions/second. */ +#define IGB_IOV_VLAN_CHANGE_BURST 64 +#define IGB_IOV_VLAN_CHANGE_INTERVAL (SBT_1S / 8) /* 82576 Datasheet rev. 2.0, Section 8.14.16: VMOLR[31] must be one. */ #define IGB_82576_VMOLR_RSV (1U << 31) #define IGB_82576_LVMMC_BLOCK_MASK 0x1c @@ -58,11 +61,13 @@ struct igb_vf { struct timeval last_mdd_log; sbintime_t mbx_retry_at; sbintime_t mdd_notify_at; + sbintime_t vlan_token_time; u16 pool; u16 rar_index; u16 max_frame_size; u16 mc_count; u16 vlan_count; + u16 vlan_tokens; u16 default_vlan; u8 mbx_retry_count; u8 mac[ETHER_ADDR_LEN]; @@ -167,6 +172,34 @@ igb_iov_nack_allowed(struct igb_vf *vf) return (ratecheck(&vf->last_nack, &igb_iov_nack_interval) != 0); } +static void +igb_iov_reset_vlan_rate(struct igb_vf *vf) +{ + + vf->vlan_token_time = getsbinuptime(); + vf->vlan_tokens = IGB_IOV_VLAN_CHANGE_BURST; +} + +static bool +igb_iov_vlan_add_allowed(struct igb_vf *vf) +{ + sbintime_t elapsed, now; + uint64_t refill; + + now = getsbinuptime(); + elapsed = now - vf->vlan_token_time; + if (elapsed >= IGB_IOV_VLAN_CHANGE_INTERVAL) { + refill = elapsed / IGB_IOV_VLAN_CHANGE_INTERVAL; + vf->vlan_tokens = min((uint64_t)IGB_IOV_VLAN_CHANGE_BURST, + vf->vlan_tokens + refill); + vf->vlan_token_time = now; + } + if (vf->vlan_tokens == 0) + return (false); + vf->vlan_tokens--; + return (true); +} + static u32 igb_iov_reply_header(u32 request, bool cts, bool ack) { @@ -642,7 +675,6 @@ igb_iov_rebuild_mta(struct e1000_softc *sc) mta[(hash >> 5) & (hw->mac.mta_reg_count - 1)] |= 1U << (hash & 0x1f); } - igb_iov_configure_vmolr(sc, vf); } changed = false; @@ -881,12 +913,17 @@ igb_iov_vlan_present(struct e1000_softc *sc, u16 vid, bool include_pf) static int igb_iov_vlan_unique_count(struct e1000_softc *sc, bool include_pf) { - int count, vid; + u32 vlans; + int count, i, word; count = 0; - for (vid = 0; vid < 4096; vid++) - if (igb_iov_vlan_present(sc, vid, include_pf)) - count++; + for (word = 0; word < EM_VFTA_SIZE; word++) { + vlans = include_pf ? sc->shadow_vfta[word] : 0; + for (i = 0; i < sc->num_vfs; i++) + if ((sc->vfs[i].flags & IGB_VF_ACTIVE) != 0) + vlans |= sc->vfs[i].vlans[word]; + count += bitcount32(vlans); + } return (count); } @@ -909,10 +946,17 @@ igb_iov_set_vlan(struct e1000_softc *sc, struct igb_vf *vf, u16 vid, if (add == present) return (0); + /* + * Removals always reduce privilege and remain available. Charge only + * additions, which a hostile VF must alternate with removals to force + * repeated global VLAN rebuilds. + */ if (add && !igb_iov_vlan_present(sc, vid, false) && igb_iov_vlan_unique_count(sc, false) >= E1000_VLVF_ARRAY_SIZE) return (ENOSPC); + if (add && !igb_iov_vlan_add_allowed(vf)) + return (EBUSY); if (add) { vf->vlans[vid >> 5] |= bit; @@ -1170,6 +1214,7 @@ igb_iov_set_multicast(struct e1000_softc *sc, struct igb_vf *vf, u32 *msg) "VF %u multicast list exceeds 30 entries; " "enabling all-multicast reception\n", vf->pool); } + igb_iov_configure_vmolr(sc, vf); igb_iov_rebuild_mta(sc); return (0); } @@ -1660,6 +1705,12 @@ igb_iov_initialize(struct e1000_softc *sc) vf = &sc->vfs[i]; if (!(vf->flags & IGB_VF_ACTIVE)) continue; + /* + * A PF-wide reset is trusted and can require a complete guest + * replay. Guest-controlled RESET and VFLR do not refill this + * allowance. + */ + igb_iov_reset_vlan_rate(vf); igb_iov_clear_mac_filters(sc, vf); igb_iov_reset_vf_state(sc, vf); igb_iov_clear_rar(sc, vf->rar_index); @@ -1875,6 +1926,7 @@ igb_if_iov_vf_add(if_ctx_t ctx, u16 vfnum, const nvlist_t *config) vf->rar_index = sc->hw.mac.rar_entry_count - (vfnum + 1); vf->max_frame_size = ETHER_MAX_LEN; vf->default_vlan = vlan; + igb_iov_reset_vlan_rate(vf); if (nvlist_exists_binary(config, "mac-addr")) { mac = nvlist_get_binary(config, "mac-addr", &mac_size); if (mac_size != ETHER_ADDR_LEN || !igb_iov_mac_valid(mac))home | help
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