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* [PATCH batadv-next v3] batman-adv: tt: batch BH re-enable during TT hash walks
@ 2026-11-08  0:01 Ömer Mete Kaya
  2026-11-08  7:35 ` Sven Eckelmann
  0 siblings, 1 reply; 5+ messages in thread
From: Ömer Mete Kaya @ 2026-11-08  0:01 UTC (permalink / raw)
  To: sven, marek.lindner, sw, antonio
  Cc: b.a.t.m.a.n, netdev, linux-kernel, davem,
	syzbot+61b202fdc410840f0198, Ömer Mete Kaya

Each spin_unlock_bh() re-enables bottom halves and, when softirqs are
pending, processes them inline before returning. During a 1024-bucket
TT hash walk under network load, the purge worker can be repeatedly
interrupted by inline softirq processing at every bucket boundary.

Replace per-bucket spin_lock_bh()/spin_unlock_bh() with an outer
local_bh_disable(), inner spin_lock()/spin_unlock(), and periodic
re-enable points via batadv_hash_bh_resched(). The helper re-enables
BH and calls cond_resched() every BATADV_HASH_BH_BUDGET (64) buckets.
The total softirq work is unchanged, but BH state transitions drop
from 1024 to ~16 per walk, reducing how often the purge loop is
interrupted.

The cond_resched() provides a voluntary preemption point on
non-PREEMPT kernels. Functions called under a spinlock or from
non-sleepable contexts cannot yield; these use the outer
local_bh_disable()/local_bh_enable() conversion without
batadv_hash_bh_resched().

The five converted hash-walking functions are:

  batadv_tt_local_purge():
    Accepts a new @may_sleep parameter. From workqueue context
    (batadv_tt_purge), may_sleep=true allows periodic yielding.
    From batadv_tt_local_resize_to_mtu(), may_sleep=false because
    the caller holds tt.commit_lock.

  batadv_tt_global_del_orig():
    Called from multiple contexts including under spinlocks
    (batadv_purge_orig_ref). Cannot yield. Converts to outer
    local_bh_disable()/local_bh_enable() with inner spin_lock()/
    spin_unlock() but does not use batadv_hash_bh_resched().

  batadv_tt_global_purge():
    Called from workqueue context; yields every 64 buckets.

  batadv_tt_local_transition_new():
  batadv_tt_local_purge_pending_clients():
    Called under tt.commit_lock. Convert to outer local_bh_disable()/
    local_bh_enable() with inner spin_lock()/spin_unlock() but do
    not use batadv_hash_bh_resched().

On PREEMPT_RT, local_bh_disable() maps to migrate_disable() and
softirqs run in dedicated kthreads, so the batching has no effect
on softirq latency but the reduced BH transition overhead still
applies.

Reported-by: syzbot+61b202fdc410840f0198@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=61b202fdc410840f0198
Signed-off-by: Ömer Mete Kaya <omermetekaya0@gmail.com>
---
Changes in v3:
  - Remove batadv_hash_bh_resched() from batadv_tt_global_del_orig():
    called under spinlocks (e.g. batadv_purge_orig_ref).
    Convert to outer local_bh_disable()/local_bh_enable() with
    inner spin_lock()/spin_unlock() only, like the commit_lock paths.
  - Fix reverse christmas tree ordering in batadv_tt_global_purge()
  - Fix Closes: URL (remove backslash escaping)

 net/batman-adv/hash.h              | 30 +++++++++++++++++++
 net/batman-adv/translation-table.c | 48 ++++++++++++++++++++++--------
 2 files changed, 65 insertions(+), 13 deletions(-)

diff --git a/net/batman-adv/hash.h b/net/batman-adv/hash.h
index 5d9a5ab..cf3ef70 100644
--- a/net/batman-adv/hash.h
+++ b/net/batman-adv/hash.h
@@ -10,10 +10,12 @@
 #include "main.h"

 #include <linux/atomic.h>
+#include <linux/bottom_half.h>
 #include <linux/compiler.h>
 #include <linux/list.h>
 #include <linux/lockdep.h>
 #include <linux/rculist.h>
+#include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
@@ -167,4 +169,32 @@ static inline void *batadv_hash_remove(struct batadv_hashtable *hash,
 	return data_save;
 }

+/* work which can be done in a hash walk before BH gets re-enabled */
+#define BATADV_HASH_BH_BUDGET 64
+
+/**
+ * batadv_hash_bh_resched() - re-enable BH after the work budget is used up
+ * @buckets_done: buckets processed since BH was disabled, reset when BH is
+ *  re-enabled
+ *
+ * A walk over all buckets of a hash disables BH only once instead of
+ * re-enabling it after each bucket. Otherwise, pending softirqs would be
+ * processed inline after each bucket. When @buckets_done reached
+ * BATADV_HASH_BH_BUDGET, BH is re-enabled to run the pending softirqs and to
+ * give other tasks a chance to run.
+ *
+ * Must be called with BH disabled, without any spinlock held and from a
+ * context which is allowed to sleep.
+ */
+static inline void batadv_hash_bh_resched(u32 *buckets_done)
+{
+	if (*buckets_done < BATADV_HASH_BH_BUDGET)
+		return;
+
+	local_bh_enable();
+	cond_resched();
+	local_bh_disable();
+	*buckets_done = 0;
+}
+
 #endif /* _NET_BATMAN_ADV_HASH_H_ */
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index b9407ad..ebeb486 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -36,6 +36,7 @@
 #include <linux/overflow.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
+#include <linux/sched.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -1892,23 +1893,32 @@ static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
  * @bat_priv: the bat priv with all the mesh interface information
  * @timeout: parameter deciding whether a given tt local entry is considered
  *  inactive or not
+ * @may_sleep: if true, periodically re-enable softirqs and yield the CPU.
+ *  Must be false when called with spinlocks held.
  */
 static void batadv_tt_local_purge(struct batadv_priv *bat_priv,
-				  int timeout)
+				  int timeout, bool may_sleep)
 {
 	spinlock_t *list_lock; /* protects write access to the hash lists */
 	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
 	struct hlist_head *head;
+	u32 buckets_done = 0;
 	u32 i;

+	local_bh_disable();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
 		list_lock = &hash->list_locks[i];

-		spin_lock_bh(list_lock);
+		spin_lock(list_lock);
 		batadv_tt_local_purge_list(bat_priv, head, timeout);
-		spin_unlock_bh(list_lock);
+		spin_unlock(list_lock);
+		buckets_done++;
+
+		if (may_sleep)
+			batadv_hash_bh_resched(&buckets_done);
 	}
+	local_bh_enable();
 }

 /**
@@ -2887,11 +2897,12 @@ void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
 	if (!hash)
 		return;

+	local_bh_disable();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
 		list_lock = &hash->list_locks[i];

-		spin_lock_bh(list_lock);
+		spin_lock(list_lock);
 		hlist_for_each_entry_safe(tt_common_entry, safe,
 					  head, hash_entry) {
 			/* remove only matching entries */
@@ -2916,8 +2927,9 @@ void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
 				batadv_tt_global_entry_put(tt_global);
 			}
 		}
-		spin_unlock_bh(list_lock);
+		spin_unlock(list_lock);
 	}
+	local_bh_enable();
 	clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
 }

@@ -2969,14 +2981,16 @@ static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
 	struct batadv_tt_global_entry *tt_global;
 	struct hlist_node *node_tmp;
 	struct hlist_head *head;
+	u32 buckets_done = 0;
 	char *msg = NULL;
 	u32 i;

+	local_bh_disable();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
 		list_lock = &hash->list_locks[i];

-		spin_lock_bh(list_lock);
+		spin_lock(list_lock);
 		hlist_for_each_entry_safe(tt_common, node_tmp, head,
 					  hash_entry) {
 			tt_global = container_of(tt_common,
@@ -2996,8 +3010,12 @@ static void batadv_tt_global_purge(struct batadv_priv *bat_priv)

 			batadv_tt_global_entry_put(tt_global);
 		}
-		spin_unlock_bh(list_lock);
+		spin_unlock(list_lock);
+		buckets_done++;
+
+		batadv_hash_bh_resched(&buckets_done);
 	}
+	local_bh_enable();
 }

 /**
@@ -4402,7 +4420,7 @@ static void batadv_tt_purge(struct work_struct *work)
 	priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
 	bat_priv = container_of(priv_tt, struct batadv_priv, tt);

-	batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT);
+	batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT, true);
 	batadv_tt_global_purge(bat_priv);
 	batadv_tt_req_purge(bat_priv);
 	batadv_tt_roam_purge(bat_priv);
@@ -4449,11 +4467,12 @@ static void batadv_tt_local_transition_new(struct batadv_priv *bat_priv)
 	if (!hash)
 		return;

+	local_bh_disable();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
 		list_lock = &hash->list_locks[i];

-		spin_lock_bh(list_lock);
+		spin_lock(list_lock);
 		hlist_for_each_entry(tt_common_entry, head, hash_entry) {
 			bool cont = false;

@@ -4472,8 +4491,9 @@ static void batadv_tt_local_transition_new(struct batadv_priv *bat_priv)
 			batadv_tt_local_size_inc(bat_priv,
 						 tt_common_entry->key.vid);
 		}
-		spin_unlock_bh(list_lock);
+		spin_unlock(list_lock);
 	}
+	local_bh_enable();
 }

 /**
@@ -4497,11 +4517,12 @@ static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
 	if (!hash)
 		return;

+	local_bh_disable();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
 		list_lock = &hash->list_locks[i];

-		spin_lock_bh(list_lock);
+		spin_lock(list_lock);
 		hlist_for_each_entry_safe(tt_common, node_tmp, head,
 					  hash_entry) {
 			bool cont = false;
@@ -4536,8 +4557,9 @@ static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)

 			batadv_tt_local_entry_put(tt_local);
 		}
-		spin_unlock_bh(list_lock);
+		spin_unlock(list_lock);
 	}
+	local_bh_enable();
 }

 /**
@@ -4839,7 +4861,7 @@ void batadv_tt_local_resize_to_mtu(struct net_device *mesh_iface)
 		if (size_max >= table_size)
 			break;

-		batadv_tt_local_purge(bat_priv, timeout);
+		batadv_tt_local_purge(bat_priv, timeout, false);
 		batadv_tt_local_purge_pending_clients(bat_priv);

 		timeout /= 2;
--
2.56.0


^ permalink raw reply	[flat|nested] 5+ messages in thread
[parent not found: <20261029135633.206144-1-omermetekaya0@gmail.com>]
* [syzbot] [netfilter?] BUG: workqueue lockup in batadv_tt_purge
@ 2026-09-15 15:10 syzbot
  2026-10-17 10:43 ` [syzbot] [arm?] " syzbot
  0 siblings, 1 reply; 5+ messages in thread
From: syzbot @ 2026-09-15 15:10 UTC (permalink / raw)
  To: davem, edumazet, fw, herbert, horms, kuba, linux-kernel, netdev,
	netfilter-devel, pabeni, pablo, steffen.klassert, syzkaller-bugs

Hello,

syzbot found the following issue on:

HEAD commit:    5445d6419962 arm64: Don't read GMID_EL1 when MTE is disabled
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1514428e580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=56ed23170c168d4c
dashboard link: https://syzkaller.appspot.com/bug?extid=61b202fdc410840f0198
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e8b70e3bd109/disk-5445d641.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e5227e56ac93/vmlinux-5445d641.xz
kernel image: https://storage.googleapis.com/syzbot-assets/54905f78be59/Image-5445d641.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+61b202fdc410840f0198@syzkaller.appspotmail.com

BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 37s!
Showing busy workqueues and worker pools:
workqueue events: flags=0x100
  pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=8 refcnt=9
    in-flight: 6264:reg_todo for 27s
    pending: 6*nsim_dev_hwstats_traffic_work, psi_avgs_work
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=11 refcnt=12
    pending: 4*nsim_dev_hwstats_traffic_work, 2*psi_avgs_work, 2*ovs_dp_masks_rebalance, free_obj_work, 2*psi_avgs_work
workqueue events_unbound: flags=0x2
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=20 refcnt=21
    in-flight: 56:cfg80211_wiphy_work for 64s cfg80211_wiphy_work ,4950:cfg80211_wiphy_work for 68s cfg80211_wiphy_work ,7165:nsim_dev_trap_report_work for 9s ,12:cfg80211_wiphy_work for 69s cfg80211_wiphy_work ,1457:cfg80211_wiphy_work for 63s cfg80211_wiphy_work
    pending: nsim_dev_trap_report_work, toggle_allocation_gate, 5*nsim_dev_trap_report_work, flush_memcg_stats_dwork, 3*nsim_dev_trap_report_work
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=8 refcnt=9
    in-flight: 52:cfg80211_wiphy_work for 67s cfg80211_wiphy_work ,13:cfg80211_wiphy_work for 67s cfg80211_wiphy_work ,40:cfg80211_wiphy_work for 62s cfg80211_wiphy_work ,264:cfg80211_wiphy_work for 34s cfg80211_wiphy_work
workqueue events_power_efficient: flags=0x82
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=8 refcnt=9
    in-flight: 1188:neigh_periodic_work for 41s ,7164:gc_worker for 2s
    pending: crda_timeout_work, neigh_periodic_work, wg_ratelimiter_gc_entries, reg_check_chans_work, 2*neigh_managed_work
workqueue events_dfl_long: flags=0x2
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=6 refcnt=7
    pending: 6*defense_work_handler
workqueue mm_percpu_wq: flags=0x108
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
    pending: vmstat_update
workqueue bat_events: flags=0x6000a
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=45 MAYDAY
    in-flight: 2852(RESCUER):batadv_tt_purge for 11s
    pending: mayday_cursor_func
    inactive: 2*batadv_tt_purge, batadv_dat_purge, 2*batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, 4*batadv_mcast_mla_update, 2*batadv_iv_send_outstanding_bat_ogm_packet, 2*batadv_purge_orig, 6*batadv_iv_send_outstanding_bat_ogm_packet, 2*batadv_purge_orig, batadv_dat_purge, batadv_bla_periodic_work, 4*batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, batadv_tt_purge, batadv_mcast_mla_update, 3*batadv_iv_send_outstanding_bat_ogm_packet, batadv_tt_purge
workqueue wg-kex-wg0: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg0: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-kex-wg1: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg1: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=3 refcnt=4
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker
workqueue wg-kex-wg2: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg2: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=3 refcnt=4
    pending: wg_packet_encrypt_worker, wg_packet_decrypt_worker, wg_packet_tx_worker
workqueue wg-crypt-wg0: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-kex-wg1: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg1: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=3 refcnt=4
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker
workqueue wg-crypt-wg2: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=3 refcnt=4
    pending: wg_packet_encrypt_worker, wg_packet_decrypt_worker, wg_packet_tx_worker
workqueue wg-kex-wg0: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg0: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-crypt-wg1: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=3 refcnt=4
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker
workqueue wg-kex-wg2: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg2: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-kex-wg0: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg0: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-kex-wg1: flags=0x6
  pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2
    pending: wg_packet_handshake_send_worker
workqueue wg-crypt-wg1: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
workqueue wg-crypt-wg2: flags=0x128
  pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3
    pending: wg_packet_encrypt_worker, wg_packet_tx_worker
pool 2: cpus=0 node=0 flags=0x0 nice=0 hung=0s workers=10 idle: 4833 9 4790 6306 5581 4834 6772 10 1009
pool 8: cpus=0-1 flags=0x6 nice=0 hung=2s workers=12 manager: 7166
Showing backtraces of busy workers in stalled worker pools:
pool 6: no worker in running state, cpu=1 is busy (nr_workers=11 nr_idle=11)
The pool might have trouble waking an idle worker.
Backtrace of last woken worker:
task:kworker/1:1     state:R  running task     stack:0     pid:26    tgid:26    ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue:  0x0 (wg-crypt-wg0)
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7362
 worker_thread+0x924/0xbd0 kernel/workqueue.c:3566
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2852 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Workqueue: bat_events batadv_tt_purge
pstate: 03400005 (nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : in_softirq_really kernel/kcov.c:167 [inline]
pc : check_kcov_mode+0x18/0x54 kernel/kcov.c:179
lr : write_comp_data+0x38/0x84 kernel/kcov.c:242
sp : ffff80008ec46dd0
x29: ffff80008ec46dd0 x28: dfff800000000000 x27: 000000000000224e
x26: dfff800000000000 x25: ffff700011d88dc8 x24: 1ffff00011d88dfa
x23: ffff0000c8e9d880 x22: 0000000000000007 x21: 0000000000000002
x20: ffff000023a0f400 x19: ffff800085709eb4 x18: 0000000011264820
x17: 0000000001320140 x16: 0140000800000000 x15: 0000000000000000
x14: 00000000850ade10 x13: 0000000000000007 x12: 0000000000000000
x11: 0000000000000000 x10: 000000000000000f x9 : 0000000000000101
x8 : ffff0000c8e9d880 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000000 x3 : ffff800085709eb4
x2 : ffff000023a0f400 x1 : ffff0000c8e9d880 x0 : 0000000000000003
Call trace:
 preempt_count arch/arm64/include/asm/preempt.h:12 [inline] (P)
 in_softirq_really kernel/kcov.c:167 [inline] (P)
 check_kcov_mode+0x18/0x54 kernel/kcov.c:179 (P)
 __sanitizer_cov_trace_const_cmp8+0x24/0x30 kernel/kcov.c:317
 __xfrm_decode_session+0x484/0x8a8 net/xfrm/xfrm_policy.c:3524
 xfrm_decode_session include/net/xfrm.h:1357 [inline]
 ip_route_me_harder+0x7c4/0xd80 net/ipv4/netfilter.c:67
 synproxy_send_tcp+0x2d4/0x5a4 net/netfilter/nf_synproxy_core.c:434
 synproxy_send_client_synack+0x3b0/0x640 net/netfilter/nf_synproxy_core.c:487
 nft_synproxy_eval_v4+0x16c/0x278 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x2d8/0x4a4 net/netfilter/nft_synproxy.c:141
 nft_synproxy_eval+0x34/0x48 net/netfilter/nft_synproxy.c:247
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x418/0x13c8 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x284/0x3d4 net/netfilter/nft_chain_filter.c:162
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xc8/0x224 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:280 [inline]
 NF_HOOK+0x1f0/0x398 include/linux/netfilter.h:323
 ip_local_deliver+0x128/0x188 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:480 [inline]
 ip_rcv_finish+0x20c/0x230 net/ipv4/ip_input.c:492
 NF_HOOK+0x308/0x398 include/linux/netfilter.h:325
 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:612
 __netif_receive_skb_one_core+0xc8/0x110 net/core/dev.c:6264
 __netif_receive_skb+0x34/0x128 net/core/dev.c:6377
 process_backlog+0x5f4/0x16f8 net/core/dev.c:6728
 __napi_poll+0xb4/0x328 net/core/dev.c:7787
 napi_poll net/core/dev.c:7850 [inline]
 net_rx_action+0x5b0/0xc14 net/core/dev.c:8007
 handle_softirqs+0x2ec/0xd98 kernel/softirq.c:645
 __do_softirq+0x14/0x20 kernel/softirq.c:679
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:78
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:885
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:83
 do_softirq+0x90/0xf8 kernel/softirq.c:546
 __local_bh_enable_ip+0x240/0x35c kernel/softirq.c:473
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:237 [inline]
 _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:245
 spin_unlock_bh include/linux/spinlock.h:407 [inline]
 batadv_tt_global_purge net/batman-adv/translation-table.c:2390 [inline]
 batadv_tt_purge+0x3e4/0x7b4 net/batman-adv/translation-table.c:3754
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0x91c/0x1250 kernel/workqueue.c:3470
 rescuer_thread+0x68c/0xd90 kernel/workqueue.c:3694
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838


---
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^ permalink raw reply	[flat|nested] 5+ messages in thread
end of thread, other threads:[~2026-11-08  8:01 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-11-08  0:01 [PATCH batadv-next v3] batman-adv: tt: batch BH re-enable during TT hash walks Ömer Mete Kaya
2026-11-08  7:35 ` Sven Eckelmann
2026-11-08  8:01   ` [syzbot] [arm?] BUG: workqueue lockup in batadv_tt_purge syzbot
     [not found] <20261029135633.206144-1-omermetekaya0@gmail.com>
2026-10-29 13:58 ` syzbot
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2026-09-15 15:10 [syzbot] [netfilter?] " syzbot
2026-10-17 10:43 ` [syzbot] [arm?] " syzbot

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