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author | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2024-12-06 12:40:11 +0000 |
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committer | Jakub Kicinski <kuba@kernel.org> | 2024-12-07 17:28:53 -0800 |
commit | 4c49f38e20a57f8abaebdf95b369295b153d1f8e (patch) | |
tree | 69c379ef9c3783a2c14ac0908947cdbc1c505b6c /drivers | |
parent | 0f6ede9fbc747e2553612271bce108f7517e7a45 (diff) | |
download | lwn-4c49f38e20a57f8abaebdf95b369295b153d1f8e.tar.gz lwn-4c49f38e20a57f8abaebdf95b369295b153d1f8e.zip |
net: stmmac: fix TSO DMA API usage causing oops
Commit 66600fac7a98 ("net: stmmac: TSO: Fix unbalanced DMA map/unmap
for non-paged SKB data") moved the assignment of tx_skbuff_dma[]'s
members to be later in stmmac_tso_xmit().
The buf (dma cookie) and len stored in this structure are passed to
dma_unmap_single() by stmmac_tx_clean(). The DMA API requires that
the dma cookie passed to dma_unmap_single() is the same as the value
returned from dma_map_single(). However, by moving the assignment
later, this is not the case when priv->dma_cap.addr64 > 32 as "des"
is offset by proto_hdr_len.
This causes problems such as:
dwc-eth-dwmac 2490000.ethernet eth0: Tx DMA map failed
and with DMA_API_DEBUG enabled:
DMA-API: dwc-eth-dwmac 2490000.ethernet: device driver tries to +free DMA memory it has not allocated [device address=0x000000ffffcf65c0] [size=66 bytes]
Fix this by maintaining "des" as the original DMA cookie, and use
tso_des to pass the offset DMA cookie to stmmac_tso_allocator().
Full details of the crashes can be found at:
https://lore.kernel.org/all/d8112193-0386-4e14-b516-37c2d838171a@nvidia.com/
https://lore.kernel.org/all/klkzp5yn5kq5efgtrow6wbvnc46bcqfxs65nz3qy77ujr5turc@bwwhelz2l4dw/
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: Thierry Reding <thierry.reding@gmail.com>
Fixes: 66600fac7a98 ("net: stmmac: TSO: Fix unbalanced DMA map/unmap for non-paged SKB data")
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Furong Xu <0x1207@gmail.com>
Link: https://patch.msgid.link/E1tJXcx-006N4Z-PC@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 9b262cdad60b..c81ea8cdfe6e 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4192,8 +4192,8 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev) struct stmmac_txq_stats *txq_stats; struct stmmac_tx_queue *tx_q; u32 pay_len, mss, queue; + dma_addr_t tso_des, des; u8 proto_hdr_len, hdr; - dma_addr_t des; bool set_ic; int i; @@ -4289,14 +4289,15 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev) /* If needed take extra descriptors to fill the remaining payload */ tmp_pay_len = pay_len - TSO_MAX_BUFF_SIZE; + tso_des = des; } else { stmmac_set_desc_addr(priv, first, des); tmp_pay_len = pay_len; - des += proto_hdr_len; + tso_des = des + proto_hdr_len; pay_len = 0; } - stmmac_tso_allocator(priv, des, tmp_pay_len, (nfrags == 0), queue); + stmmac_tso_allocator(priv, tso_des, tmp_pay_len, (nfrags == 0), queue); /* In case two or more DMA transmit descriptors are allocated for this * non-paged SKB data, the DMA buffer address should be saved to |