msm: ipa3: add lock for num_q6_rule
There is a race condition be observed
on global variable num_q6_rule used in
ipa wan-driver. The fix is to add lock
to prevent different threads are accessing
it at the same time.
Change-Id: Ia9190c60361cb5605b61963309beca3acdeac89d
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>
diff --git a/drivers/platform/msm/ipa/ipa_v2/rmnet_ipa.c b/drivers/platform/msm/ipa/ipa_v2/rmnet_ipa.c
index 9c75202..2f272d2 100644
--- a/drivers/platform/msm/ipa/ipa_v2/rmnet_ipa.c
+++ b/drivers/platform/msm/ipa/ipa_v2/rmnet_ipa.c
@@ -411,12 +411,15 @@
{
int i, j;
+ /* prevent multi-threads accessing num_q6_rule */
+ mutex_lock(&add_mux_channel_lock);
if (rule_req->filter_spec_list_valid == true) {
num_q6_rule = rule_req->filter_spec_list_len;
IPAWANDBG("Received (%d) install_flt_req\n", num_q6_rule);
} else {
num_q6_rule = 0;
IPAWANERR("got no UL rules from modem\n");
+ mutex_unlock(&add_mux_channel_lock);
return -EINVAL;
}
@@ -610,9 +613,11 @@
num_q6_rule = 0;
memset(ipa_qmi_ctx->q6_ul_filter_rule, 0,
sizeof(ipa_qmi_ctx->q6_ul_filter_rule));
+ mutex_unlock(&add_mux_channel_lock);
return -EINVAL;
success:
+ mutex_unlock(&add_mux_channel_lock);
return 0;
}
@@ -1621,9 +1626,12 @@
/* already got Q6 UL filter rules*/
if (ipa_qmi_ctx &&
ipa_qmi_ctx->modem_cfg_emb_pipe_flt
- == false)
+ == false) {
+ /* protect num_q6_rule */
+ mutex_lock(&add_mux_channel_lock);
rc = wwan_add_ul_flt_rule_to_ipa();
- else
+ mutex_unlock(&add_mux_channel_lock);
+ } else
rc = 0;
egress_set = true;
if (rc)