git.openwrt.org Git - openwrt/staging/stintel.git/blob

   1 From 38358fa3cc8e16c6862a3e5c5c233f9f652e3a6d Mon Sep 17 00:00:00 2001
   2 From: Lorenzo Bianconi <lorenzo@kernel.org>
   3 Date: Thu, 31 Jul 2025 12:29:08 +0200
   4 Subject: [PATCH] net: airoha: Fix PPE table access in
   5  airoha_ppe_debugfs_foe_show()
   6
   7 In order to avoid any possible race we need to hold the ppe_lock
   8 spinlock accessing the hw PPE table. airoha_ppe_foe_get_entry routine is
   9 always executed holding ppe_lock except in airoha_ppe_debugfs_foe_show
  10 routine. Fix the problem introducing airoha_ppe_foe_get_entry_locked
  11 routine.
  12
  13 Fixes: 3fe15c640f380 ("net: airoha: Introduce PPE debugfs support")
  14 Reviewed-by: Dawid Osuchowski <dawid.osuchowski@linux.intel.com>
  15 Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
  16 Link: https://patch.msgid.link/20250731-airoha_ppe_foe_get_entry_locked-v2-1-50efbd8c0fd6@kernel.org
  17 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
  18 ---
  19  drivers/net/ethernet/airoha/airoha_ppe.c | 26 ++++++++++++++++++------
  20  1 file changed, 20 insertions(+), 6 deletions(-)
  21
  22 --- a/drivers/net/ethernet/airoha/airoha_ppe.c
  23 +++ b/drivers/net/ethernet/airoha/airoha_ppe.c
  24 @@ -508,9 +508,11 @@ static void airoha_ppe_foe_flow_stats_up
  25                 FIELD_PREP(AIROHA_FOE_IB2_NBQ, nbq);
  26  }
  27
  28 -struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe,
  29 -                                                 u32 hash)
  30 +static struct airoha_foe_entry *
  31 +airoha_ppe_foe_get_entry_locked(struct airoha_ppe *ppe, u32 hash)
  32  {
  33 +       lockdep_assert_held(&ppe_lock);
  34 +
  35         if (hash < PPE_SRAM_NUM_ENTRIES) {
  36                 u32 *hwe = ppe->foe + hash * sizeof(struct airoha_foe_entry);
  37                 struct airoha_eth *eth = ppe->eth;
  38 @@ -537,6 +539,18 @@ struct airoha_foe_entry *airoha_ppe_foe_
  39         return ppe->foe + hash * sizeof(struct airoha_foe_entry);
  40  }
  41
  42 +struct airoha_foe_entry *airoha_ppe_foe_get_entry(struct airoha_ppe *ppe,
  43 +                                                 u32 hash)
  44 +{
  45 +       struct airoha_foe_entry *hwe;
  46 +
  47 +       spin_lock_bh(&ppe_lock);
  48 +       hwe = airoha_ppe_foe_get_entry_locked(ppe, hash);
  49 +       spin_unlock_bh(&ppe_lock);
  50 +
  51 +       return hwe;
  52 +}
  53 +
  54  static bool airoha_ppe_foe_compare_entry(struct airoha_flow_table_entry *e,
  55                                          struct airoha_foe_entry *hwe)
  56  {
  57 @@ -651,7 +665,7 @@ airoha_ppe_foe_commit_subflow_entry(stru
  58         struct airoha_flow_table_entry *f;
  59         int type;
  60
  61 -       hwe_p = airoha_ppe_foe_get_entry(ppe, hash);
  62 +       hwe_p = airoha_ppe_foe_get_entry_locked(ppe, hash);
  63         if (!hwe_p)
  64                 return -EINVAL;
  65
  66 @@ -703,7 +717,7 @@ static void airoha_ppe_foe_insert_entry(
  67
  68         spin_lock_bh(&ppe_lock);
  69
  70 -       hwe = airoha_ppe_foe_get_entry(ppe, hash);
  71 +       hwe = airoha_ppe_foe_get_entry_locked(ppe, hash);
  72         if (!hwe)
  73                 goto unlock;
  74
  75 @@ -818,7 +832,7 @@ airoha_ppe_foe_flow_l2_entry_update(stru
  76                 u32 ib1, state;
  77                 int idle;
  78
  79 -               hwe = airoha_ppe_foe_get_entry(ppe, iter->hash);
  80 +               hwe = airoha_ppe_foe_get_entry_locked(ppe, iter->hash);
  81                 if (!hwe)
  82                         continue;
  83
  84 @@ -855,7 +869,7 @@ static void airoha_ppe_foe_flow_entry_up
  85         if (e->hash == 0xffff)
  86                 goto unlock;
  87
  88 -       hwe_p = airoha_ppe_foe_get_entry(ppe, e->hash);
  89 +       hwe_p = airoha_ppe_foe_get_entry_locked(ppe, e->hash);
  90         if (!hwe_p)
  91                 goto unlock;
  92