FAILED: patch "[PATCH] i40e: add mask to apply valid bits for itr_idx" failed to apply to 5.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x eac04428abe9f9cb203ffae4600791ea1d24eb18
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025092927-captivate-suspense-fdf7@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From eac04428abe9f9cb203ffae4600791ea1d24eb18 Mon Sep 17 00:00:00 2001
From: Lukasz Czapnik <lukasz.czapnik@intel.com>
Date: Wed, 13 Aug 2025 12:45:17 +0200
Subject: [PATCH] i40e: add mask to apply valid bits for itr_idx

The ITR index (itr_idx) is only 2 bits wide. When constructing the
register value for QINT_RQCTL, all fields are ORed together. Without
masking, higher bits from itr_idx may overwrite adjacent fields in the
register.

Apply I40E_QINT_RQCTL_ITR_INDX_MASK to ensure only the intended bits are
set.

Fixes: 5c3c48ac6bf5 ("i40e: implement virtual device interface")
Cc: stable@vger.kernel.org
Signed-off-by: Lukasz Czapnik <lukasz.czapnik@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index f29941c00342..f9b2197f0942 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -448,7 +448,7 @@ static void i40e_config_irq_link_list(struct i40e_vf *vf, u16 vsi_id,
 		    (qtype << I40E_QINT_RQCTL_NEXTQ_TYPE_SHIFT) |
 		    (pf_queue_id << I40E_QINT_RQCTL_NEXTQ_INDX_SHIFT) |
 		    BIT(I40E_QINT_RQCTL_CAUSE_ENA_SHIFT) |
-		    (itr_idx << I40E_QINT_RQCTL_ITR_INDX_SHIFT);
+		    FIELD_PREP(I40E_QINT_RQCTL_ITR_INDX_MASK, itr_idx);
 		wr32(hw, reg_idx, reg);
 	}