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authorPhilippe Schenker <philippe.schenker@toradex.com>2022-05-19 14:57:48 +0200
committerPhilippe Schenker <philippe.schenker@toradex.com>2022-05-19 14:57:48 +0200
commit0e61b511dd8474280ba674590daa55f30433b7d4 (patch)
tree48c35f63dc1101d0d528b5d79c81849b99ca7c6d /net/core/drop_monitor.c
parentc4bda7fe18b3ff6898f8fa110a3d60ee8f4379a0 (diff)
parent01565c91b789a1612051e735a65f11096a6f08e8 (diff)
Merge tag 'v5.4.193' into update-to-2.3.7__5.4-2.3.x-imx
This is the 5.4.193 stable release Conflicts: arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts drivers/edac/synopsys_edac.c drivers/mmc/host/sdhci-esdhc-imx.c drivers/mmc/host/sdhci.c drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c sound/soc/codecs/msm8916-wcd-analog.c
Diffstat (limited to 'net/core/drop_monitor.c')
-rw-r--r--net/core/drop_monitor.c11
1 files changed, 9 insertions, 2 deletions
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index af0130039f37..e8e8389ddc96 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -277,13 +277,17 @@ static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi,
rcu_read_lock();
list_for_each_entry_rcu(new_stat, &hw_stats_list, list) {
+ struct net_device *dev;
+
/*
* only add a note to our monitor buffer if:
* 1) this is the dev we received on
* 2) its after the last_rx delta
* 3) our rx_dropped count has gone up
*/
- if ((new_stat->dev == napi->dev) &&
+ /* Paired with WRITE_ONCE() in dropmon_net_event() */
+ dev = READ_ONCE(new_stat->dev);
+ if ((dev == napi->dev) &&
(time_after(jiffies, new_stat->last_rx + dm_hw_check_delta)) &&
(napi->dev->stats.rx_dropped != new_stat->last_drop_val)) {
trace_drop_common(NULL, NULL);
@@ -1497,7 +1501,10 @@ static int dropmon_net_event(struct notifier_block *ev_block,
mutex_lock(&net_dm_mutex);
list_for_each_entry_safe(new_stat, tmp, &hw_stats_list, list) {
if (new_stat->dev == dev) {
- new_stat->dev = NULL;
+
+ /* Paired with READ_ONCE() in trace_napi_poll_hit() */
+ WRITE_ONCE(new_stat->dev, NULL);
+
if (trace_state == TRACE_OFF) {
list_del_rcu(&new_stat->list);
kfree_rcu(new_stat, rcu);