diff options
| author | Eric Joyner <eric.joyner@amd.com> | 2026-07-22 21:13:42 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-07-27 18:23:07 -0700 |
| commit | 97ac08560d236ca17f6606d9e671118e5eae5721 (patch) | |
| tree | 21a9aa4043048e84431edb540f983cfdadbd5895 /include/linux | |
| parent | 6fb7b769d6ed6d1d2e02af4a80e57a2477f35086 (diff) | |
ethtool: Embed FEC hist ranges as buffer in struct
When a driver's .get_fec_stats() handler is called and the driver
supports FEC histogram stats, the driver supplies the histogram bin
ranges via a pointer. This pointer is assigned while under the netdev
ops lock in fec_prepare_data(), but the actual data is only read after
the lock is released; so this allows the driver to change the ranges
(e.g. from another .get_fec_stats() call) while the current call chain
is reading them in fec_fill_reply().
Fix this by adding an ethtool core-owned buffer, ranges_buf, to struct
ethtool_fec_hist. Drivers whose ranges are built dynamically (currently
just mlx5) fill ranges_buf and then point the existing ranges pointer at
it, giving ethtool a consistent copy that stays valid after the netdev
ops lock is dropped and later in fec_fill_reply(). Drivers whose ranges
are compile-time constants (bnxt, netdevsim) are unaffected by the
potential race and keep setting the existing ranges pointer to their
constant array, without making copies.
Fixes: cc2f08129925 ("ethtool: add FEC bins histogram report")
Signed-off-by: Eric Joyner <eric.joyner@amd.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260723041342.39238-1-eric.joyner@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/ethtool.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 5d491a98265e..12683b5d125e 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -562,6 +562,7 @@ struct ethtool_fec_hist { u64 per_lane[ETHTOOL_MAX_LANES]; } values[ETHTOOL_FEC_HIST_MAX]; const struct ethtool_fec_hist_range *ranges; + struct ethtool_fec_hist_range ranges_buf[ETHTOOL_FEC_HIST_MAX]; }; /** * struct ethtool_fec_stats - statistics for IEEE 802.3 FEC |