Re: [net-next,v4,9/9] ice: dpll: Support E825-C SyncE and dynamic pin discovery
From: Simon Horman <horms@kernel.org>
Date: 2026-02-03 16:11:41
Also in:
intel-wired-lan, linux-rdma, lkml
This is an AI-generated review of your patch. The human sending this email has considered the AI review valid, or at least plausible. For local reproduction steps see https://netdev-ai.bots.linux.dev/ai-local.html --- ice: dpll: Support E825-C SyncE and dynamic pin discovery This patch implements SyncE support for the E825-C Ethernet controller using the DPLL subsystem, with dynamic pin discovery via firmware (ACPI) and asynchronous registration using the DPLL notifier chain.
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diff --git a/drivers/net/ethernet/intel/ice/ice_dpll.c b/drivers/net/ethernet/intel/ice/ice_dpll.c index 4eca62688d83..a8c99e49bfae 100644 --- a/drivers/net/ethernet/intel/ice/ice_dpll.c +++ b/drivers/net/ethernet/intel/ice/ice_dpll.c
[ ... ]
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@@ -528,6 +529,92 @@ ice_dpll_pin_disable(struct ice_hw *hw, struct ice_dpll_pin *pin, return ret; } +/** + * ice_dpll_rclk_update - updates the state of rclk pin on a device + * @pf: private board struct + * @pin: pointer to a pin + * @port_num: port number + * + * Update struct holding pin states info, states are separate for each parent + * + * Context: Called under pf->dplls.lock + * Return: + * * 0 - OK + * * negative - error + */ +static int ice_dpll_rclk_update(struct ice_pf *pf, struct ice_dpll_pin *pin, + u8 port_num) +{ + int ret; + + for (u8 parent = 0; parent < pf->dplls.rclk.num_parents; parent++) { + ret = ice_aq_get_phy_rec_clk_out(&pf->hw, &parent, &port_num, + &pin->flags[parent], NULL);
Is it safe to pass &parent as an output parameter when it's also the loop
counter? Looking at ice_aq_get_phy_rec_clk_out():
int ice_aq_get_phy_rec_clk_out(struct ice_hw *hw, u8 *phy_output, ...)
{
cmd->phy_output = *phy_output; // Read as input
status = ice_aq_send_cmd(hw, &desc, NULL, 0, NULL);
if (!status) {
*phy_output = cmd->phy_output; // Write back from firmware
...
The firmware could potentially return a different value than was sent,
which would be written back to 'parent', corrupting the loop counter.
This corrupted value is then used as an array index:
+ if (ret) + return ret; + + ice_dpll_pin_store_state(pin, parent, + ICE_AQC_GET_PHY_REC_CLK_OUT_OUT_EN & + pin->flags[parent]);
Both pin->flags[parent] and pin->state[parent] (inside ice_dpll_pin_store_state) could access out of bounds if firmware returns a value >= ICE_DPLL_RCLK_NUM_MAX (which is 2). Would it be safer to use a separate variable for the phy_output parameter and validate that firmware echoes back the expected value?
+ } + + return 0; +}
[ ... ]
quoted hunk ↗ jump to hunk
@@ -3239,8 +3683,8 @@ static int ice_dpll_init_pins(struct ice_pf *pf, bool cgu) * @d: pointer to ice_dpll * @cgu: if cgu is present and controlled by this NIC * - * If cgu is owned unregister the dpll from dpll subsystem. - * Release resources of dpll device from dpll subsystem. + * If cgu is owned, unregister the DPL from DPLL subsystem. + * Release resources of DPLL device from DPLL subsystem. */
This isn't a bug, but there's a typo: 'DPL' should be 'DPLL'.