| Message ID | 20220819110519.1230877-1-saproj@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 0ee7828dfc56e97d71e51e6374dc7b4eb2b6e081 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] net: moxa: get rid of asymmetry in DMA mapping/unmapping | expand |
On Fri, Aug 19, 2022 at 02:05:19PM +0300, Sergei Antonov wrote: > Since priv->rx_mapping[i] is maped in moxart_mac_open(), we > should unmap it from moxart_mac_stop(). Fixes 2 warnings. > > 1. During error unwinding in moxart_mac_probe(): "goto init_fail;", > then moxart_mac_free_memory() calls dma_unmap_single() with > priv->rx_mapping[i] pointers zeroed. > > WARNING: CPU: 0 PID: 1 at kernel/dma/debug.c:963 check_unmap+0x704/0x980 > DMA-API: moxart-ethernet 92000000.mac: device driver tries to free DMA memory it has not allocated [device address=0x0000000000000000] [size=1600 bytes] > CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0+ #60 > Hardware name: Generic DT based system > unwind_backtrace from show_stack+0x10/0x14 > show_stack from dump_stack_lvl+0x34/0x44 > dump_stack_lvl from __warn+0xbc/0x1f0 > __warn from warn_slowpath_fmt+0x94/0xc8 > warn_slowpath_fmt from check_unmap+0x704/0x980 > check_unmap from debug_dma_unmap_page+0x8c/0x9c > debug_dma_unmap_page from moxart_mac_free_memory+0x3c/0xa8 > moxart_mac_free_memory from moxart_mac_probe+0x190/0x218 > moxart_mac_probe from platform_probe+0x48/0x88 > platform_probe from really_probe+0xc0/0x2e4 > > 2. After commands: > ip link set dev eth0 down > ip link set dev eth0 up > > WARNING: CPU: 0 PID: 55 at kernel/dma/debug.c:570 add_dma_entry+0x204/0x2ec > DMA-API: moxart-ethernet 92000000.mac: cacheline tracking EEXIST, overlapping mappings aren't supported > CPU: 0 PID: 55 Comm: ip Not tainted 5.19.0+ #57 > Hardware name: Generic DT based system > unwind_backtrace from show_stack+0x10/0x14 > show_stack from dump_stack_lvl+0x34/0x44 > dump_stack_lvl from __warn+0xbc/0x1f0 > __warn from warn_slowpath_fmt+0x94/0xc8 > warn_slowpath_fmt from add_dma_entry+0x204/0x2ec > add_dma_entry from dma_map_page_attrs+0x110/0x328 > dma_map_page_attrs from moxart_mac_open+0x134/0x320 > moxart_mac_open from __dev_open+0x11c/0x1ec > __dev_open from __dev_change_flags+0x194/0x22c > __dev_change_flags from dev_change_flags+0x14/0x44 > dev_change_flags from devinet_ioctl+0x6d4/0x93c > devinet_ioctl from inet_ioctl+0x1ac/0x25c > > v1 -> v2: > Extraneous change removed. > > Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver") > Signed-off-by: Sergei Antonov <saproj@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
Hello: This patch was applied to netdev/net.git (master) by Jakub Kicinski <kuba@kernel.org>: On Fri, 19 Aug 2022 14:05:19 +0300 you wrote: > Since priv->rx_mapping[i] is maped in moxart_mac_open(), we > should unmap it from moxart_mac_stop(). Fixes 2 warnings. > > 1. During error unwinding in moxart_mac_probe(): "goto init_fail;", > then moxart_mac_free_memory() calls dma_unmap_single() with > priv->rx_mapping[i] pointers zeroed. > > [...] Here is the summary with links: - [v2] net: moxa: get rid of asymmetry in DMA mapping/unmapping https://git.kernel.org/netdev/net/c/0ee7828dfc56 You are awesome, thank you!
diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c index 19009a6bd33a..9e57d23e57bf 100644 --- a/drivers/net/ethernet/moxa/moxart_ether.c +++ b/drivers/net/ethernet/moxa/moxart_ether.c @@ -71,11 +71,6 @@ static int moxart_set_mac_address(struct net_device *ndev, void *addr) static void moxart_mac_free_memory(struct net_device *ndev) { struct moxart_mac_priv_t *priv = netdev_priv(ndev); - int i; - - for (i = 0; i < RX_DESC_NUM; i++) - dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], - priv->rx_buf_size, DMA_FROM_DEVICE); if (priv->tx_desc_base) dma_free_coherent(&priv->pdev->dev, @@ -187,6 +182,7 @@ static int moxart_mac_open(struct net_device *ndev) static int moxart_mac_stop(struct net_device *ndev) { struct moxart_mac_priv_t *priv = netdev_priv(ndev); + int i; napi_disable(&priv->napi); @@ -198,6 +194,11 @@ static int moxart_mac_stop(struct net_device *ndev) /* disable all functions */ writel(0, priv->base + REG_MAC_CTRL); + /* unmap areas mapped in moxart_mac_setup_desc_ring() */ + for (i = 0; i < RX_DESC_NUM; i++) + dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], + priv->rx_buf_size, DMA_FROM_DEVICE); + return 0; }
Since priv->rx_mapping[i] is maped in moxart_mac_open(), we should unmap it from moxart_mac_stop(). Fixes 2 warnings. 1. During error unwinding in moxart_mac_probe(): "goto init_fail;", then moxart_mac_free_memory() calls dma_unmap_single() with priv->rx_mapping[i] pointers zeroed. WARNING: CPU: 0 PID: 1 at kernel/dma/debug.c:963 check_unmap+0x704/0x980 DMA-API: moxart-ethernet 92000000.mac: device driver tries to free DMA memory it has not allocated [device address=0x0000000000000000] [size=1600 bytes] CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0+ #60 Hardware name: Generic DT based system unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x34/0x44 dump_stack_lvl from __warn+0xbc/0x1f0 __warn from warn_slowpath_fmt+0x94/0xc8 warn_slowpath_fmt from check_unmap+0x704/0x980 check_unmap from debug_dma_unmap_page+0x8c/0x9c debug_dma_unmap_page from moxart_mac_free_memory+0x3c/0xa8 moxart_mac_free_memory from moxart_mac_probe+0x190/0x218 moxart_mac_probe from platform_probe+0x48/0x88 platform_probe from really_probe+0xc0/0x2e4 2. After commands: ip link set dev eth0 down ip link set dev eth0 up WARNING: CPU: 0 PID: 55 at kernel/dma/debug.c:570 add_dma_entry+0x204/0x2ec DMA-API: moxart-ethernet 92000000.mac: cacheline tracking EEXIST, overlapping mappings aren't supported CPU: 0 PID: 55 Comm: ip Not tainted 5.19.0+ #57 Hardware name: Generic DT based system unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x34/0x44 dump_stack_lvl from __warn+0xbc/0x1f0 __warn from warn_slowpath_fmt+0x94/0xc8 warn_slowpath_fmt from add_dma_entry+0x204/0x2ec add_dma_entry from dma_map_page_attrs+0x110/0x328 dma_map_page_attrs from moxart_mac_open+0x134/0x320 moxart_mac_open from __dev_open+0x11c/0x1ec __dev_open from __dev_change_flags+0x194/0x22c __dev_change_flags from dev_change_flags+0x14/0x44 dev_change_flags from devinet_ioctl+0x6d4/0x93c devinet_ioctl from inet_ioctl+0x1ac/0x25c v1 -> v2: Extraneous change removed. Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver") Signed-off-by: Sergei Antonov <saproj@gmail.com> --- drivers/net/ethernet/moxa/moxart_ether.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)