On Mon, 2022-02-28 at 15:03 +0000, Adrien TREMOT wrote: > Hi, > > It seems the issue was linked to the 8139cp NIC driver. > I changed the NIC driver to virtio and the stall did not occure anymore. > Let me know if you need more informations about this or if I should signal the issue somewhere else. My memory is that the 8139cp emulation in QEMU has very poor performance (the physical device was only designed for 100 Mbit/s Ethernet anyway) and is not suitable for use in production. If virtio_net is working for you then I don't think this bug is worth investigating. But if you would like to investigate this, you could try applying the attached patch and switching back to 8139cp temporarily. Instructions for rebuilding a kernel package can be found in the debian-kernel- handbook package at file:///usr/share/doc/debian-kernel-handbook/kernel-handbook.html/ch-common-tasks.html#s-common-official (This is normally also available online but that server is currently down.) Ben. -- Ben Hutchings The first rule of tautology club is the first rule of tautology club.
From 139819f9b8009144f15a6659ce767023a0583ef8 Mon Sep 17 00:00:00 2001
From: Ben Hutchings <ben@decadent.org.uk>
Date: Mon, 28 Feb 2022 17:44:27 +0100
Subject: [PATCH] 8139cp: Count Rx failures towards polling budget
In cp_rx_poll() the loop condition is 'while (rx < budget)', but in
error cases it moves on to the next descriptor without incrementing
rx. This is not correct and can lead to a soft lockup.
Reported-by: Adrien TREMOT <a.tremot@alphalink.fr>
Fixes: bea3348eef27 ("[NET]: Make NAPI polling independent of struct ...")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/net/ethernet/realtek/8139cp.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/realtek/8139cp.c b/drivers/net/ethernet/realtek/8139cp.c
index ad7b9e9d7f95..063a4dc338cc 100644
--- a/drivers/net/ethernet/realtek/8139cp.c
+++ b/drivers/net/ethernet/realtek/8139cp.c
@@ -535,7 +535,6 @@ static int cp_rx_poll(struct napi_struct *napi, int budget)
cp->rx_skb[rx_tail] = new_skb;
cp_rx_skb(cp, skb, desc);
- rx++;
mapping = new_mapping;
rx_next:
@@ -547,6 +546,8 @@ static int cp_rx_poll(struct napi_struct *napi, int budget)
else
desc->opts1 = cpu_to_le32(DescOwn | cp->rx_buf_sz);
rx_tail = NEXT_RX(rx_tail);
+
+ rx++;
}
cp->rx_tail = rx_tail;
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