Subject: [PATCH AUTOSEL 4.4 01/12] bnxt_en: reinitialize IRQs when MTU is modified

From: Sasha Levin <[email-masked]>
Date: Wed, 18 Mar 2020 16:56:37 -0400

From: Vasundhara Volam <[email-masked]>

[ Upstream commit a9b952d267e59a3b405e644930f46d252cea7122 ]

MTU changes may affect the number of IRQs so we must call
bnxt_close_nic()/bnxt_open_nic() with the irq_re_init parameter
set to true.  The reason is that a larger MTU may require
aggregation rings not needed with smaller MTU.  We may not be
able to allocate the required number of aggregation rings and
so we reduce the number of channels which will change the number
of IRQs.  Without this patch, it may crash eventually in
pci_disable_msix() when the IRQs are not properly unwound.

Fixes: c0c050c58d84 ("bnxt_en: New Broadcom ethernet driver.")
Signed-off-by: Vasundhara Volam <[email-masked]>
Signed-off-by: Michael Chan <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 81282b811a6cd..d91953eabfeb4 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -5310,13 +5310,13 @@ static int bnxt_change_mtu(struct net_device *dev, int new_mtu)
 		return -EINVAL;
 
 	if (netif_running(dev))
-		bnxt_close_nic(bp, false, false);
+		bnxt_close_nic(bp, true, false);
 
 	dev->mtu = new_mtu;
 	bnxt_set_ring_params(bp);
 
 	if (netif_running(dev))
-		return bnxt_open_nic(bp, false, false);
+		return bnxt_open_nic(bp, true, false);
 
 	return 0;
 }
-- 
2.20.1