On s390, the following build warning occurs: drivers/net/ethernet/marvell/mvpp2/mvpp2.h:844:2: warning: overflow in conversion from 'long unsigned int' to 'int' changes value from '18446744073709551584' to '-32' [-Woverflow] 844 | ((total_size) - MVPP2_SKB_HEADROOM - MVPP2_SKB_SHINFO_SIZE) This happens because MVPP2_SKB_SHINFO_SIZE, which is 320 bytes (which is already 64-byte aligned) on some architectures, actually gets ALIGN'd up to 512 bytes in the s390 case. So then, when this is invoked: MVPP2_RX_MAX_PKT_SIZE(MVPP2_BM_SHORT_FRAME_SIZE) ...that turns into: 704 - 224 - 512 == -32 ...which is not a good frame size to end up with! The warning above is a bit lucky: it notices a signed/unsigned bad behavior here, which leads to the real problem of a frame that is too short for its contents. Increase MVPP2_BM_SHORT_FRAME_SIZE by 32 (from 704 to 736), which is just exactly big enough. (The other values can't readily be changed without causing a lot of other problems.) Fixes: 07dd0a7aae7f ("mvpp2: add basic XDP support") Cc: Sven Auhagen <sven.auhagen@voleatech.de> Cc: Matteo Croce <mcroce@microsoft.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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 Restructured Text 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.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%