hak5
/
openwrt
mirror of https://github.com/hak5/openwrt.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

ipq40xx: essedma: Fix dead lock 

edma_read_append_stats() gets called from two places in the driver.
The first place is the kernel timer that periodically updates
the statistics, so nothing gets lost due to overflows.
The second one it's part of the userspace ethtool ioctl handler
to provide up-to-date values.

For this configuration, the use of spin_lock() is not sufficient
and as per:
<https://mirrors.edge.kernel.org/pub/linux/kernel/people/rusty/kernel-locking/c214.html>
the locking has to be upgraded to spin_lock_bh().

Signed-off-by: Masafumi UTSUGI <mutsugi@allied-telesis.co.jp>
[folded patch into 710-, rewrote message]
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
master
Masafumi UTSUGI 2019-10-01 18:59:18 +09:00 committed by Christian Lamparter
parent f5c7fe2ff0
commit f1d761f95e
2 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
target/linux/ipq40xx/patches-4.14/710-net-add-qualcomm-essedma-ethernet-driver.patch
View File

@ -2775,7 +2775,7 @@ Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
+ int i;
+ u32 stat;
+
+ spin_lock(&edma_cinfo->stats_lock);
+ spin_lock_bh(&edma_cinfo->stats_lock);
+ p = (uint32_t *)&(edma_cinfo->edma_ethstats);
+
+ for (i = 0; i < EDMA_MAX_TRANSMIT_QUEUE; i++) {
@ -2802,7 +2802,7 @@ Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
+ p++;
+ }
+
+ spin_unlock(&edma_cinfo->stats_lock);
+ spin_unlock_bh(&edma_cinfo->stats_lock);
+}
+
+static void edma_statistics_timer(unsigned long data)

4
target/linux/ipq40xx/patches-4.19/710-net-add-qualcomm-essedma-ethernet-driver.patch
View File

@ -2774,7 +2774,7 @@ Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
+ int i;
+ u32 stat;
+
+ spin_lock(&edma_cinfo->stats_lock);
+ spin_lock_bh(&edma_cinfo->stats_lock);
+ p = (uint32_t *)&(edma_cinfo->edma_ethstats);
+
+ for (i = 0; i < EDMA_MAX_TRANSMIT_QUEUE; i++) {
@ -2801,7 +2801,7 @@ Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
+ p++;
+ }
+
+ spin_unlock(&edma_cinfo->stats_lock);
+ spin_unlock_bh(&edma_cinfo->stats_lock);
+}
+
+static void edma_statistics_timer(struct timer_list *t)