From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CAD2613E024; Wed, 3 Jul 2024 11:21:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720005670; cv=none; b=ZMqdeGyLvx9d3o76lKlsSsIIxyqH/5kswo/9fVjIbJqCBd5Mgx3L+28CM7Es8WMUpiK2jGOUA3IxTXRBT2Bu+D/XHKx1d4qi5PQcbVZGbz+ADBVYKLvG+mu0aI6iurLrsiH9hCCF9j6D/UGHcnCN/OtG7vzzFtqITjUiQQhTHjo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720005670; c=relaxed/simple; bh=Y3+Q2oxihdfMiw0Tql8A0u1Eric2YyqRcnCxwxeTmtc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AjFSJr2DQpDkM355A1zKeYPD2uFzqFger9Bqcd8yNB5VOEAcgto5K2tjm0bWDvqQMgZ93KiwtmVHvO2KjCZQ3mHFluNtbRYIwDhtsllCHUTiDP1txr9hRb3/ltW+/Gyw1yedQWV6g9ge7X6LtSEtM7fdWMPWg9NbBNkPorBn1as= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Fc7RA7hN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Fc7RA7hN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51911C2BD10; Wed, 3 Jul 2024 11:21:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1720005670; bh=Y3+Q2oxihdfMiw0Tql8A0u1Eric2YyqRcnCxwxeTmtc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fc7RA7hNGROZrmgNTxdSSWjtrRNdTxVLHxgE0OYZK+63noGSHDrZnQuy2FPYqV8Wq LYjyVF53Pfp/GBLop0zvqCEXDm84wKa/Mlvfpi20L5JYFbRitkR1dyuLNH0aYHWL8W GhpLLm7ZFwOKAnpyNSZDGeU+xy1zl0z2Hj0J3Nng= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Sven Eckelmann , Simon Wunderlich , Sasha Levin Subject: [PATCH 5.15 158/356] batman-adv: bypass empty buckets in batadv_purge_orig_ref() Date: Wed, 3 Jul 2024 12:38:14 +0200 Message-ID: <20240703102919.080788967@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240703102913.093882413@linuxfoundation.org> References: <20240703102913.093882413@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 40dc8ab605894acae1473e434944924a22cfaaa0 ] Many syzbot reports are pointing to soft lockups in batadv_purge_orig_ref() [1] Root cause is unknown, but we can avoid spending too much time there and perhaps get more interesting reports. [1] watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [kworker/u4:6:621] Modules linked in: irq event stamp: 6182794 hardirqs last enabled at (6182793): [] __local_bh_enable_ip+0x224/0x44c kernel/softirq.c:386 hardirqs last disabled at (6182794): [] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (6182794): [] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (6182792): [] spin_unlock_bh include/linux/spinlock.h:396 [inline] softirqs last enabled at (6182792): [] batadv_purge_orig_ref+0x114c/0x1228 net/batman-adv/originator.c:1287 softirqs last disabled at (6182790): [] spin_lock_bh include/linux/spinlock.h:356 [inline] softirqs last disabled at (6182790): [] batadv_purge_orig_ref+0x164/0x1228 net/batman-adv/originator.c:1271 CPU: 0 PID: 621 Comm: kworker/u4:6 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: bat_events batadv_purge_orig pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : should_resched arch/arm64/include/asm/preempt.h:79 [inline] pc : __local_bh_enable_ip+0x228/0x44c kernel/softirq.c:388 lr : __local_bh_enable_ip+0x224/0x44c kernel/softirq.c:386 sp : ffff800099007970 x29: ffff800099007980 x28: 1fffe00018fce1bd x27: dfff800000000000 x26: ffff0000d2620008 x25: ffff0000c7e70de8 x24: 0000000000000001 x23: 1fffe00018e57781 x22: dfff800000000000 x21: ffff80008aab71c4 x20: ffff0001b40136c0 x19: ffff0000c72bbc08 x18: 1fffe0001a817bb0 x17: ffff800125414000 x16: ffff80008032116c x15: 0000000000000001 x14: 1fffe0001ee9d610 x13: 0000000000000000 x12: 0000000000000003 x11: 0000000000000000 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : 00000000005e5789 x7 : ffff80008aab61dc x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000006 x1 : 0000000000000080 x0 : ffff800125414000 Call trace: __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline] arch_local_irq_enable arch/arm64/include/asm/irqflags.h:49 [inline] __local_bh_enable_ip+0x228/0x44c kernel/softirq.c:386 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_purge_orig_ref+0x114c/0x1228 net/batman-adv/originator.c:1287 batadv_purge_orig+0x20/0x70 net/batman-adv/originator.c:1300 process_one_work+0x694/0x1204 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2787 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:51 lr : default_idle_call+0xf8/0x128 kernel/sched/idle.c:103 sp : ffff800093a17d30 x29: ffff800093a17d30 x28: dfff800000000000 x27: 1ffff00012742fb4 x26: ffff80008ec9d000 x25: 0000000000000000 x24: 0000000000000002 x23: 1ffff00011d93a74 x22: ffff80008ec9d3a0 x21: 0000000000000000 x20: ffff0000c19dbc00 x19: ffff8000802d0fd8 x18: 1fffe00036804396 x17: ffff80008ec9d000 x16: ffff8000802d089c x15: 0000000000000001 x14: 1fffe00036805f10 x13: 0000000000000000 x12: 0000000000000003 x11: 0000000000000001 x10: 0000000000000003 x9 : 0000000000000000 x8 : 00000000000ce8d1 x7 : ffff8000804609e4 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff80008ad6aac0 x2 : 0000000000000000 x1 : ffff80008aedea60 x0 : ffff800125436000 Call trace: __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline] arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:49 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x1f0/0x4e8 kernel/sched/idle.c:312 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:410 secondary_start_kernel+0x198/0x1c0 arch/arm64/kernel/smp.c:272 __secondary_switched+0xb8/0xbc arch/arm64/kernel/head.S:404 Signed-off-by: Eric Dumazet Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin --- net/batman-adv/originator.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index aadc653ca1d80..b6367a7576750 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -1238,6 +1238,8 @@ void batadv_purge_orig_ref(struct batadv_priv *bat_priv) /* for all origins... */ for (i = 0; i < hash->size; i++) { head = &hash->table[i]; + if (hlist_empty(head)) + continue; list_lock = &hash->list_locks[i]; spin_lock_bh(list_lock); -- 2.43.0