| 1 |
From 1707ea46020f07a9226c3e1485a74a3f5a25eae2 Mon Sep 17 00:00:00 2001 |
| 2 |
From: Sasha Levin <sashal@kernel.org> |
| 3 |
Date: Fri, 19 Aug 2022 14:05:19 +0300 |
| 4 |
Subject: net: moxa: get rid of asymmetry in DMA mapping/unmapping |
| 5 |
|
| 6 |
From: Sergei Antonov <saproj@gmail.com> |
| 7 |
|
| 8 |
[ Upstream commit 0ee7828dfc56e97d71e51e6374dc7b4eb2b6e081 ] |
| 9 |
|
| 10 |
Since priv->rx_mapping[i] is maped in moxart_mac_open(), we |
| 11 |
should unmap it from moxart_mac_stop(). Fixes 2 warnings. |
| 12 |
|
| 13 |
1. During error unwinding in moxart_mac_probe(): "goto init_fail;", |
| 14 |
then moxart_mac_free_memory() calls dma_unmap_single() with |
| 15 |
priv->rx_mapping[i] pointers zeroed. |
| 16 |
|
| 17 |
WARNING: CPU: 0 PID: 1 at kernel/dma/debug.c:963 check_unmap+0x704/0x980 |
| 18 |
DMA-API: moxart-ethernet 92000000.mac: device driver tries to free DMA memory it has not allocated [device address=0x0000000000000000] [size=1600 bytes] |
| 19 |
CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0+ #60 |
| 20 |
Hardware name: Generic DT based system |
| 21 |
unwind_backtrace from show_stack+0x10/0x14 |
| 22 |
show_stack from dump_stack_lvl+0x34/0x44 |
| 23 |
dump_stack_lvl from __warn+0xbc/0x1f0 |
| 24 |
__warn from warn_slowpath_fmt+0x94/0xc8 |
| 25 |
warn_slowpath_fmt from check_unmap+0x704/0x980 |
| 26 |
check_unmap from debug_dma_unmap_page+0x8c/0x9c |
| 27 |
debug_dma_unmap_page from moxart_mac_free_memory+0x3c/0xa8 |
| 28 |
moxart_mac_free_memory from moxart_mac_probe+0x190/0x218 |
| 29 |
moxart_mac_probe from platform_probe+0x48/0x88 |
| 30 |
platform_probe from really_probe+0xc0/0x2e4 |
| 31 |
|
| 32 |
2. After commands: |
| 33 |
ip link set dev eth0 down |
| 34 |
ip link set dev eth0 up |
| 35 |
|
| 36 |
WARNING: CPU: 0 PID: 55 at kernel/dma/debug.c:570 add_dma_entry+0x204/0x2ec |
| 37 |
DMA-API: moxart-ethernet 92000000.mac: cacheline tracking EEXIST, overlapping mappings aren't supported |
| 38 |
CPU: 0 PID: 55 Comm: ip Not tainted 5.19.0+ #57 |
| 39 |
Hardware name: Generic DT based system |
| 40 |
unwind_backtrace from show_stack+0x10/0x14 |
| 41 |
show_stack from dump_stack_lvl+0x34/0x44 |
| 42 |
dump_stack_lvl from __warn+0xbc/0x1f0 |
| 43 |
__warn from warn_slowpath_fmt+0x94/0xc8 |
| 44 |
warn_slowpath_fmt from add_dma_entry+0x204/0x2ec |
| 45 |
add_dma_entry from dma_map_page_attrs+0x110/0x328 |
| 46 |
dma_map_page_attrs from moxart_mac_open+0x134/0x320 |
| 47 |
moxart_mac_open from __dev_open+0x11c/0x1ec |
| 48 |
__dev_open from __dev_change_flags+0x194/0x22c |
| 49 |
__dev_change_flags from dev_change_flags+0x14/0x44 |
| 50 |
dev_change_flags from devinet_ioctl+0x6d4/0x93c |
| 51 |
devinet_ioctl from inet_ioctl+0x1ac/0x25c |
| 52 |
|
| 53 |
v1 -> v2: |
| 54 |
Extraneous change removed. |
| 55 |
|
| 56 |
Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver") |
| 57 |
Signed-off-by: Sergei Antonov <saproj@gmail.com> |
| 58 |
Reviewed-by: Andrew Lunn <andrew@lunn.ch> |
| 59 |
Link: https://lore.kernel.org/r/20220819110519.1230877-1-saproj@gmail.com |
| 60 |
Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| 61 |
Signed-off-by: Sasha Levin <sashal@kernel.org> |
| 62 |
--- |
| 63 |
drivers/net/ethernet/moxa/moxart_ether.c | 11 ++++++----- |
| 64 |
1 file changed, 6 insertions(+), 5 deletions(-) |
| 65 |
|
| 66 |
diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c |
| 67 |
index f11f1cb92025f..3b6beb96ca856 100644 |
| 68 |
--- a/drivers/net/ethernet/moxa/moxart_ether.c |
| 69 |
+++ b/drivers/net/ethernet/moxa/moxart_ether.c |
| 70 |
@@ -74,11 +74,6 @@ static int moxart_set_mac_address(struct net_device *ndev, void *addr) |
| 71 |
static void moxart_mac_free_memory(struct net_device *ndev) |
| 72 |
{ |
| 73 |
struct moxart_mac_priv_t *priv = netdev_priv(ndev); |
| 74 |
- int i; |
| 75 |
- |
| 76 |
- for (i = 0; i < RX_DESC_NUM; i++) |
| 77 |
- dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], |
| 78 |
- priv->rx_buf_size, DMA_FROM_DEVICE); |
| 79 |
|
| 80 |
if (priv->tx_desc_base) |
| 81 |
dma_free_coherent(&priv->pdev->dev, |
| 82 |
@@ -193,6 +188,7 @@ static int moxart_mac_open(struct net_device *ndev) |
| 83 |
static int moxart_mac_stop(struct net_device *ndev) |
| 84 |
{ |
| 85 |
struct moxart_mac_priv_t *priv = netdev_priv(ndev); |
| 86 |
+ int i; |
| 87 |
|
| 88 |
napi_disable(&priv->napi); |
| 89 |
|
| 90 |
@@ -204,6 +200,11 @@ static int moxart_mac_stop(struct net_device *ndev) |
| 91 |
/* disable all functions */ |
| 92 |
writel(0, priv->base + REG_MAC_CTRL); |
| 93 |
|
| 94 |
+ /* unmap areas mapped in moxart_mac_setup_desc_ring() */ |
| 95 |
+ for (i = 0; i < RX_DESC_NUM; i++) |
| 96 |
+ dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], |
| 97 |
+ priv->rx_buf_size, DMA_FROM_DEVICE); |
| 98 |
+ |
| 99 |
return 0; |
| 100 |
} |
| 101 |
|
| 102 |
-- |
| 103 |
2.35.1 |
| 104 |
|
Parent Directory
| 
Revision Log