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 4A87C140397 for ; Mon, 8 Apr 2024 15:41:30 +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=1712590890; cv=none; b=qzq4Ruf9xyz/qNaj8yy6C4eElGuAXkQ6I3AdiGh9VUVMIRpkra4WGOT+zF5zKRJPpRkjRu1SrA6oGC5/5387EwaAoKfNSAhDJEWV7oYz8AEhh2qwnUY3pPQEVuGB7RNocZon3lexRFIYV9TDMicpGeg7DESXWZgzeTHjy32O3Sc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712590890; c=relaxed/simple; bh=D3PbVJvm979q3w4tHYroApm4q4tNgSz8oq/V9TMJkbk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Ou/7+9RJjIMNdUh71NQEqvjEItt9WzWIEnC4MHvdNvzK4aVvVMVyHFisde/0TapSoobTYf+LqBABr2ZoiMq9MZ3I2fy6fVKrL/gpIh3DKJfZaLMK46PLjiUf94eXMQcyHxuBP/y28NeH3MjtsmzDiHcgDvIZBddTRYb7Wkf8JlA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qjypb048; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qjypb048" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A8AAC433F1; Mon, 8 Apr 2024 15:41:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712590889; bh=D3PbVJvm979q3w4tHYroApm4q4tNgSz8oq/V9TMJkbk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qjypb048ZqE+l45tCwluhgdcRE2rZXs0Ewe7KcaevVtHi6ZrW/q+DCfh3KEa/LZ+i HWr6dbL3ZE/WkdLbc4VGjUaspLjKm6YrYHkHDVitRp6rNPDva6TAEQXnLHuD1taXy2 VWDvuhFS87knjrJkc7D6BCv/KPCjzHSN3bbTyzkZ8y9w+HQEt4s0PhCezw9X/SzCsn vrewavZ0yRfNzEKKAL1wnhRkrS6LfZuDcoRKCc3bNRFcJEuS63W4sMQQZqWg0wZCRl G9srpVLVy/Usdydnn0z6mIcvL8Dnw5BjAY9XqdqUFBXU+sk8quHxDT3Hu1eNLN/qUk DQmzGSErG8jqQ== Date: Mon, 8 Apr 2024 16:41:24 +0100 From: Simon Horman To: Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, eric.dumazet@gmail.com, Marek Lindner , Simon Wunderlich , Antonio Quartulli , Sven Eckelmann Subject: Re: [PATCH net-next] batman-adv: bypass empty buckets in batadv_purge_orig_ref() Message-ID: <20240408154124.GJ26556@kernel.org> References: <20240330155438.2462326-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240330155438.2462326-1-edumazet@google.com> On Sat, Mar 30, 2024 at 03:54:38PM +0000, Eric Dumazet wrote: > 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 > Cc: Marek Lindner > Cc: Simon Wunderlich > Cc: Antonio Quartulli > Cc: Sven Eckelmann Reviewed-by: Simon Horman