[PATCH iwl-net v3 0/6] ixgbe: six bug fixes

[Aleksandr Loktionov <aleksandr.loktionov@intel.com>]

Six fixes for the ixgbe driver, covering a SWFW semaphore timeout
miscalculation, a security-relevant debugfs out-of-bounds, a broken
flow-control NVM-reset path, a false-success return in the cls_u32
nexthdr path, an adaptive-ITR u8 overflow, and wrong bit positions in
the UP-to-TC register normalisation.

Patches 1-3 fix issues that could result in functional regressions
(FW update failures, OOB MMIO, traffic stall after NVM update).
Patches 4-6 fix correctness bugs with user-visible effects.

Patch 3 guards against calling setup_fc() on 82599 backplane links:
on those interfaces setup_fc() resolves to prot_autoc_write() ->
ixgbe_reset_pipeline_82599(), which toggles IXGBE_AUTOC_AN_RESTART
and causes an infinite link-flap loop.  setup_fc() is now skipped for
ixgbe_media_type_backplane; fc_enable() is still called.  The failure-
path guard introduced in v2 (skip fc_enable when setup_fc fails) is
preserved.

Patch 5 reworks the ITR write-back to keep the mode flag
(IXGBE_ITR_ADAPTIVE_LATENCY, bit 7) and the usec delay in separate
operands until the final store, and clamps the delay to
[IXGBE_ITR_ADAPTIVE_MIN_USECS, IXGBE_ITR_ADAPTIVE_MAX_USECS] via
clamp_val().

Patch 6 corrects the Fixes: tag to 8b1c0b24d9af ("ixgbe: configure
minimal packet buffers to support TC") per Simon Horman.

Changes in v3:
 - cover: removed Patch 1 squash-history description (v1->v2 background
          no longer needed in the cover letter).
 - 1/6: add Reviewed-by: Simon Horman, Reviewed-by: Jacob Keller;
        no code change (Jacob suggested read_poll_timeout() but
        accepted as-is for net).
 - 2/6: add Reviewed-by: Simon Horman; no code change.
 - 3/6: add backplane-link guard in ixgbe_watchdog_update_link();
        skip setup_fc() when media type is ixgbe_media_type_backplane
        to prevent infinite link-flap on 82599 backplane interfaces.
 - 4/6: add Reviewed-by: Simon Horman; no code change.
 - 5/6: rework clamping -- use clamp_val() with mode and delay as
        separate operands; clamp to [IXGBE_ITR_ADAPTIVE_MIN_USECS,
        IXGBE_ITR_ADAPTIVE_MAX_USECS] instead of LATENCY-1.
 - 6/6: correct Fixes: tag to 8b1c0b24d9af; add Reviewed-by:
        Simon Horman.

Changes in v2:
 - 1/6: Squash two patches; fix commit msg ("200ms" -> "1s"); three
        explicit mac.type == comparisons instead of range check.
 - 2/6: Add Fixes: tag; reroute from iwl-next to iwl-net.
 - 3/6: Add Fixes: tag; reroute to iwl-net; skip fc_enable() when
        setup_fc() fails to avoid committing stale FC state.
 - 4/6: Add Fixes: tag; reroute from iwl-next to iwl-net.
 - 5/6: Add proper [N/M] patch numbering.
 - 6/6: Reroute to iwl-net; swap to (expr >> ..) & MASK operand order.

---

Aleksandr Loktionov (5):
  ixgbe: fix SWFW semaphore timeout for X550 family
  ixgbe: call ixgbe_setup_fc() before fc_enable() after NVM update
  ixgbe: fix cls_u32 nexthdr path returning success when no entry installed
  ixgbe: fix ITR value overflow in adaptive interrupt throttling
  ixgbe: fix integer overflow and wrong bit position in ixgbe_validate_rtr()

Paul Greenwalt (1):
  ixgbe: add bounds check for debugfs register access

 drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c |  4 ++--
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c    | 18 ++++++++++++------
 drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c    |  8 ++++++++
 3 files changed, 22 insertions(+), 8 deletions(-)
-- 
2.52.0