From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793214275; b=FcFpPO9thWqug2DCh77rHGxkBwPFPg/mlCom1TbXXLyP6LBmYSlZGHxw62kgRGV/EIHl cDvbIHkqW70Db4z/M64Gt+0Hx0FwuYI8OCs6Lk2GABnPNah7De7w+Mq+ZWpr2s77FPkUk gIDPqWh/RYDQ/4dzAEdumGVXtx6gXrFD9v6CA8pLUNkgEjCfeuyOZEB1y1brSgH/YJeOb QHmJXivdgkivC8/QWALykODqqrSddCEH0h2w42jI7xJdwMwFYIF129ibpDsuyExQJ2HIJ iFi6rjAPZTsTX306k9W7QwBcJbO7MF7ov3INZfiMbsd1FD0opgFnVKfoHfsdM5oF5GQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793214275; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=mQ7lWxrJrOqloPP55YAVvP1TUERxnKNW9RJ/UF+yYF8=; b=wxkQ31v97N7LxfwcmpPnuqF7cmnoqD7RkHllyECGrn0CjsrfzT9AqrE4yuGR/6d4ZDGB UzLLp0ILxyds2CoVRe6DdE5L13weg03tdsrEQZRw1oFO8LohqgvcR7WsrlNJtR2z4KGAe Ltr3MZQcF/8fu/8K0raX+5il8iSTNwUYiWRfZTKiVs08PcSf9LtfRobmite9Dkn8eoXpw yGFswegnofpIXZ6v+GZuPZh0SAdc2ewbcxuF+DctpTH0Mde03eKwBrt5ubEDyJxuJQof8 i2UxOH6XbcV9KgQGoJQAxuDF2bkbDV/O9rS0qoLiZLFNgQ7001J077lMIKmotPd+tvQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Cr+En43e; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 803CA60A5BC5; Wed, 28 Oct 2026 19:04:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Cr+En43e Received: by smtp.kernel.org (Postfix) with ESMTPSA id D5A881F01829; Wed, 28 Oct 2026 19:04:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793214275; bh=mQ7lWxrJrOqloPP55YAVvP1TUERxnKNW9RJ/UF+yYF8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Cr+En43en5cACLZ46vA05HH3rr6cWr3XE9K6GEUgIYHIYERAmwP2ciqJN/cK67l/8 r+EN5T7SgjDBQfLpBzddkOzYVyNshjl6JA1uToTWiB9CJrAQkOrRRy/M3NCOK0TmUv vB07HvB7LWzTzqtDNeec7yiEBzeoWsAFCyN4SAQM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrew Rzeznik , Yan Zhai , Jesper Dangaard Brouer , Michael Chan , Andy Gospodarek , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 0800/1887] bnxt: properly flush XDP redirect lists Date: Wed, 28 Oct 2026 17:48:16 +0100 Message-ID: <20261028170517.635067017@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yan Zhai [ Upstream commit 9caca6ac0e26cd20efd490d8b3b2ffb1c7c00f6f ] We encountered following crash when testing a XDP_REDIRECT feature in production: [56251.579676] list_add corruption. next->prev should be prev (ffff93120dd40f30), but was ffffb301ef3a6740. (next=ffff93120dd 40f30). [56251.601413] ------------[ cut here ]------------ [56251.611357] kernel BUG at lib/list_debug.c:29! [56251.621082] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [56251.632073] CPU: 111 UID: 0 PID: 0 Comm: swapper/111 Kdump: loaded Tainted: P O 6.12.33-cloudflare-2025.6. 3 #1 [56251.653155] Tainted: [P]=PROPRIETARY_MODULE, [O]=OOT_MODULE [56251.663877] Hardware name: MiTAC GC68B-B8032-G11P6-GPU/S8032GM-HE-CFR, BIOS V7.020.B10-sig 01/22/2025 [56251.682626] RIP: 0010:__list_add_valid_or_report+0x4b/0xa0 [56251.693203] Code: 0e 48 c7 c7 68 e7 d9 97 e8 42 16 fe ff 0f 0b 48 8b 52 08 48 39 c2 74 14 48 89 f1 48 c7 c7 90 e7 d9 97 48 89 c6 e8 25 16 fe ff <0f> 0b 4c 8b 02 49 39 f0 74 14 48 89 d1 48 c7 c7 e8 e7 d9 97 4c 89 [56251.725811] RSP: 0018:ffff93120dd40b80 EFLAGS: 00010246 [56251.736094] RAX: 0000000000000075 RBX: ffffb301e6bba9d8 RCX: 0000000000000000 [56251.748260] RDX: 0000000000000000 RSI: ffff9149afda0b80 RDI: ffff9149afda0b80 [56251.760349] RBP: ffff9131e49c8000 R08: 0000000000000000 R09: ffff93120dd40a18 [56251.772382] R10: ffff9159cf2ce1a8 R11: 0000000000000003 R12: ffff911a80850000 [56251.784364] R13: ffff93120fbc7000 R14: 0000000000000010 R15: ffff9139e7510e40 [56251.796278] FS: 0000000000000000(0000) GS:ffff9149afd80000(0000) knlGS:0000000000000000 [56251.809133] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [56251.819561] CR2: 00007f5e85e6f300 CR3: 00000038b85e2006 CR4: 0000000000770ef0 [56251.831365] PKRU: 55555554 [56251.838653] Call Trace: [56251.845560] [56251.851943] cpu_map_enqueue.cold+0x5/0xa [56251.860243] xdp_do_redirect+0x2d9/0x480 [56251.868388] bnxt_rx_xdp+0x1d8/0x4c0 [bnxt_en] [56251.877028] bnxt_rx_pkt+0x5f7/0x19b0 [bnxt_en] [56251.885665] ? cpu_max_write+0x1e/0x100 [56251.893510] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.902276] __bnxt_poll_work+0x190/0x340 [bnxt_en] [56251.911058] bnxt_poll+0xab/0x1b0 [bnxt_en] [56251.919041] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.927568] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.935958] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.944250] __napi_poll+0x2b/0x160 [56251.951155] bpf_trampoline_6442548651+0x79/0x123 [56251.959262] __napi_poll+0x5/0x160 [56251.966037] net_rx_action+0x3d2/0x880 [56251.973133] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.981265] ? srso_alias_return_thunk+0x5/0xfbef5 [56251.989262] ? __hrtimer_run_queues+0x162/0x2a0 [56251.996967] ? srso_alias_return_thunk+0x5/0xfbef5 [56252.004875] ? srso_alias_return_thunk+0x5/0xfbef5 [56252.012673] ? bnxt_msix+0x62/0x70 [bnxt_en] [56252.019903] handle_softirqs+0xcf/0x270 [56252.026650] irq_exit_rcu+0x67/0x90 [56252.032933] common_interrupt+0x85/0xa0 [56252.039498] [56252.044246] [56252.048935] asm_common_interrupt+0x26/0x40 [56252.055727] RIP: 0010:cpuidle_enter_state+0xb8/0x420 [56252.063305] Code: dc 01 00 00 e8 f9 79 3b ff e8 64 f7 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 a5 32 3a ff 45 84 ff 0f 85 ae 01 00 00 fb 45 85 f6 <0f> 88 88 01 00 00 48 8b 04 24 49 63 ce 4c 89 ea 48 6b f1 68 48 29 [56252.088911] RSP: 0018:ffff93120c97fe98 EFLAGS: 00000202 [56252.096912] RAX: ffff9149afd80000 RBX: ffff9141d3a72800 RCX: 0000000000000000 [56252.106844] RDX: 00003329176c6b98 RSI: ffffffe36db3fdc7 RDI: 0000000000000000 [56252.116733] RBP: 0000000000000002 R08: 0000000000000002 R09: 000000000000004e [56252.126652] R10: ffff9149afdb30c4 R11: 071c71c71c71c71c R12: ffffffff985ff860 [56252.136637] R13: 00003329176c6b98 R14: 0000000000000002 R15: 0000000000000000 [56252.146667] ? cpuidle_enter_state+0xab/0x420 [56252.153909] cpuidle_enter+0x2d/0x40 [56252.160360] do_idle+0x176/0x1c0 [56252.166456] cpu_startup_entry+0x29/0x30 [56252.173248] start_secondary+0xf7/0x100 [56252.179941] common_startup_64+0x13e/0x141 [56252.186886] >>From the crash dump, we found that the cpu_map_flush_list inside redirect info is partially corrupted: its list_head->next points to itself, but list_head->prev points to a valid list of unflushed bq entries. This turned out to be a result of missed XDP flush on redirect lists. By digging in the actual source code, we found that commit 7f0a168b0441 ("bnxt_en: Add completion ring pointer in TX and RX ring structures") incorrectly overwrites the event mask for XDP_REDIRECT in bnxt_rx_xdp. We can stably reproduce this crash by returning XDP_TX and XDP_REDIRECT randomly for incoming packets in a naive XDP program. Properly propagate the XDP_REDIRECT events back fixes the crash. Fixes: a7559bc8c17c ("bnxt: support transmit and free of aggregation buffers") Tested-by: Andrew Rzeznik Signed-off-by: Yan Zhai Acked-by: Jesper Dangaard Brouer Reviewed-by: Michael Chan Reviewed-by: Andy Gospodarek Link: https://patch.msgid.link/aFl7jpCNzscumuN2@debian.debian Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 321504790948f..de7bef33641a8 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -2543,6 +2543,7 @@ static int __bnxt_poll_work(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, { struct bnxt_napi *bnapi = cpr->bnapi; u32 raw_cons = cpr->cp_raw_cons; + bool flush_xdp = false; u32 cons; int tx_pkts = 0; int rx_pkts = 0; @@ -2580,6 +2581,8 @@ static int __bnxt_poll_work(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, else rc = bnxt_force_rx_discard(bp, cpr, &raw_cons, &event); + if (event & BNXT_REDIRECT_EVENT) + flush_xdp = true; if (likely(rc >= 0)) rx_pkts += rc; /* Increment rx_pkts when rc is -ENOMEM to count towards @@ -2607,7 +2610,7 @@ static int __bnxt_poll_work(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, } } - if (event & BNXT_REDIRECT_EVENT) + if (flush_xdp) xdp_do_flush(); if (event & BNXT_TX_EVENT) { -- 2.53.0