]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
ice: fix receive buffer size miscalculation
authorJesse Brandeburg <jesse.brandeburg@intel.com>
Thu, 10 Aug 2023 23:51:10 +0000 (16:51 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 30 Aug 2023 14:18:14 +0000 (16:18 +0200)
commitd7823d752ce1112efc3857d4b272180c13a83a83
tree6cba1d637a3234c062ccd7b68c841f6468d4377e
parentace1b0ae309720634f8aa553cdc89dbea80c2322
ice: fix receive buffer size miscalculation

[ Upstream commit 10083aef784031fa9f06c19a1b182e6fad5338d9 ]

The driver is misconfiguring the hardware for some values of MTU such that
it could use multiple descriptors to receive a packet when it could have
simply used one.

Change the driver to use a round-up instead of the result of a shift, as
the shift can truncate the lower bits of the size, and result in the
problem noted above. It also aligns this driver with similar code in i40e.

The insidiousness of this problem is that everything works with the wrong
size, it's just not working as well as it could, as some MTU sizes end up
using two or more descriptors, and there is no way to tell that is
happening without looking at ice_trace or a bus analyzer.

Fixes: efc2214b6047 ("ice: Add support for XDP")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/ethernet/intel/ice/ice_base.c