From 38358fa3cc8e16c6862a3e5c5c233f9f652e3a6d Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Thu, 31 Jul 2025 12:29:08 +0200 Subject: [PATCH] net: airoha: Fix PPE table access in airoha_ppe_debugfs_foe_show() In order to avoid any possible race we need to hold the ppe_lock spinlock accessing the hw PPE table. airoha_ppe_foe_get_entry routine is always executed holding ppe_lock except in airoha_ppe_debugfs_foe_show routine. Fix the problem introducing airoha_ppe_foe_get_entry_locked routine. Fixes: 3fe15c640f380 ("net: airoha: Introduce PPE debugfs support") Reviewed-by: Dawid Osuchowski Signed-off-by: Lorenzo Bianconi Link: https://patch.msgid.link/20250731-airoha_ppe_foe_get_entry_locked-v2-1-50efbd8c0fd6@kernel.org Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/airoha/airoha_ppe.c | 26 ++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/airoha/airoha_ppe.c b/drivers/net/ethernet/airoha/airoha_ppe.c index c354d536bc66..47411d2cbd28 100644 --- a/drivers/net/ethernet/airoha/airoha_ppe.c +++ b/drivers/net/ethernet/airoha/airoha_ppe.c @@ -508,9 +508,11 @@ static void airoha_ppe_foe_flow_stats_update(struct airoha_ppe *ppe, FIELD_PREP(AIROHA_FOE_IB2_NBQ, nbq); } -struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe, - u32 hash) +static struct airoha_foe_entry * +airoha_ppe_foe_get_entry_locked(struct airoha_ppe *ppe, u32 hash) { + lockdep_assert_held(&ppe_lock); + if (hash < PPE_SRAM_NUM_ENTRIES) { u32 *hwe = ppe->foe + hash * sizeof(struct airoha_foe_entry); struct airoha_eth *eth = ppe->eth; @@ -537,6 +539,18 @@ struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe, return ppe->foe + hash * sizeof(struct airoha_foe_entry); } +struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe, + u32 hash) +{ + struct airoha_foe_entry *hwe; + + spin_lock_bh(&ppe_lock); + hwe = airoha_ppe_foe_get_entry_locked(ppe, hash); + spin_unlock_bh(&ppe_lock); + + return hwe; +} + static bool airoha_ppe_foe_compare_entry(struct airoha_flow_table_entry *e, struct airoha_foe_entry *hwe) { @@ -651,7 +665,7 @@ airoha_ppe_foe_commit_subflow_entry(struct airoha_ppe *ppe, struct airoha_flow_table_entry *f; int type; - hwe_p = airoha_ppe_foe_get_entry(ppe, hash); + hwe_p = airoha_ppe_foe_get_entry_locked(ppe, hash); if (!hwe_p) return -EINVAL; @@ -703,7 +717,7 @@ static void airoha_ppe_foe_insert_entry(struct airoha_ppe *ppe, spin_lock_bh(&ppe_lock); - hwe = airoha_ppe_foe_get_entry(ppe, hash); + hwe = airoha_ppe_foe_get_entry_locked(ppe, hash); if (!hwe) goto unlock; @@ -818,7 +832,7 @@ airoha_ppe_foe_flow_l2_entry_update(struct airoha_ppe *ppe, u32 ib1, state; int idle; - hwe = airoha_ppe_foe_get_entry(ppe, iter->hash); + hwe = airoha_ppe_foe_get_entry_locked(ppe, iter->hash); if (!hwe) continue; @@ -855,7 +869,7 @@ static void airoha_ppe_foe_flow_entry_update(struct airoha_ppe *ppe, if (e->hash == 0xffff) goto unlock; - hwe_p = airoha_ppe_foe_get_entry(ppe, e->hash); + hwe_p = airoha_ppe_foe_get_entry_locked(ppe, e->hash); if (!hwe_p) goto unlock; -- 2.25.1