Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Kaige Li <likaige@loongson.cn>
To:     "David S. Miller" <davem@davemloft.net>,
        Christian Benvenuti <benve@cisco.com>,
        Govindarajulu Varadarajan <_govind@gmx.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Xuefeng Li <lixuefeng@loongson.cn>,
        Tiezhu Yang <yangtiezhu@loongson.cn>
Subject: [PATCH RESEND] net/cisco: Fix a sleep-in-atomic-context bug in enic_init_affinity_hint()
Date:   Tue, 23 Jun 2020 16:13:09 +0800
Message-Id: <1592899989-22049-1-git-send-email-likaige@loongson.cn>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

The kernel module may sleep with holding a spinlock.

The function call paths (from bottom to top) are:

[FUNC] zalloc_cpumask_var(GFP_KERNEL)
drivers/net/ethernet/cisco/enic/enic_main.c, 125: zalloc_cpumask_var in enic_init_affinity_hint
drivers/net/ethernet/cisco/enic/enic_main.c, 1918: enic_init_affinity_hint in enic_open
drivers/net/ethernet/cisco/enic/enic_main.c, 2348: enic_open in enic_reset
drivers/net/ethernet/cisco/enic/enic_main.c, 2341: spin_lock in enic_reset

To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC.

Signed-off-by: Kaige Li <likaige@loongson.cn>
---

+cc netdev@vger.kernel.org

 drivers/net/ethernet/cisco/enic/enic_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index cd5fe4f..ee62065 100644
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -122,7 +122,7 @@ static void enic_init_affinity_hint(struct enic *enic)
 		     !cpumask_empty(enic->msix[i].affinity_mask)))
 			continue;
 		if (zalloc_cpumask_var(&enic->msix[i].affinity_mask,
-				       GFP_KERNEL))
+				       GFP_ATOMIC))
 			cpumask_set_cpu(cpumask_local_spread(i, numa_node),
 					enic->msix[i].affinity_mask);
 	}
-- 
2.1.0