Patch "[PATCH 018/135] fm10k: do not assume VF always has 1 queue" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    [PATCH 018/135] fm10k: do not assume VF always has 1 queue

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     0018-fm10k-do-not-assume-VF-always-has-1-queue.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 34411f1bdb573a3cb8eb77133dcbfe8f042ae5e7 Mon Sep 17 00:00:00 2001
From: Jacob Keller <jacob.e.keller@intel.com>
Date: Mon, 24 Aug 2015 17:27:24 -0700
Subject: [PATCH 018/135] fm10k: do not assume VF always has 1 queue

[ Upstream commit 1340181fe435ccb8ca2f996b8680bd9566860619 ]

It is possible that the PF has not yet assigned resources to the VF.
Although rare, this could result in the VF attempting to read queues it
does not own and result in FUM or THI faults in the PF. To prevent this,
check queue 0 before we continue in init_hw_vf.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/intel/fm10k/fm10k_type.h |    1 +
 drivers/net/ethernet/intel/fm10k/fm10k_vf.c   |    7 ++++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/intel/fm10k/fm10k_type.h
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_type.h
@@ -77,6 +77,7 @@ struct fm10k_hw;
 #define FM10K_PCIE_SRIOV_CTRL_VFARI		0x10
 
 #define FM10K_ERR_PARAM				-2
+#define FM10K_ERR_NO_RESOURCES			-3
 #define FM10K_ERR_REQUESTS_PENDING		-4
 #define FM10K_ERR_RESET_REQUESTED		-5
 #define FM10K_ERR_DMA_PENDING			-6
--- a/drivers/net/ethernet/intel/fm10k/fm10k_vf.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_vf.c
@@ -103,7 +103,12 @@ static s32 fm10k_init_hw_vf(struct fm10k
 	s32 err;
 	u16 i;
 
-	/* assume we always have at least 1 queue */
+	/* verify we have at least 1 queue */
+	if (!~fm10k_read_reg(hw, FM10K_TXQCTL(0)) ||
+	    !~fm10k_read_reg(hw, FM10K_RXQCTL(0)))
+		return FM10K_ERR_NO_RESOURCES;
+
+	/* determine how many queues we have */
 	for (i = 1; tqdloc0 && (i < FM10K_MAX_QUEUES_POOL); i++) {
 		/* verify the Descriptor cache offsets are increasing */
 		tqdloc = ~fm10k_read_reg(hw, FM10K_TQDLOC(i));


Patches currently in stable-queue which might be from jacob.e.keller@intel.com are

queue-4.4/0022-fm10k-always-check-init_hw-for-errors.patch
queue-4.4/0021-fm10k-reset-max_queues-on-init_hw_vf-failure.patch
queue-4.4/0023-fm10k-reinitialize-queuing-scheme-after-calling-init.patch
queue-4.4/0018-fm10k-do-not-assume-VF-always-has-1-queue.patch
queue-4.4/0019-fm10k-Correct-MTU-for-jumbo-frames.patch