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Commit66600fac7a("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:66600fac7a("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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.