This is a note to let you know that I've just added the patch titled
vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation
to the 5.10-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:
vhost_vdpa-fix-the-missing-irq_bypass_unregister_producer-invocation.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4c050286bb202cffd5467c1cba982dff391d62e1 Mon Sep 17 00:00:00 2001
From: Gautam Dawar <gdawar.xilinx@xxxxxxxxx>
Date: Wed, 24 Feb 2021 17:18:45 +0530
Subject: vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation
From: Gautam Dawar <gdawar.xilinx@xxxxxxxxx>
commit 4c050286bb202cffd5467c1cba982dff391d62e1 upstream.
When qemu with vhost-vdpa netdevice is run for the first time,
it works well. But after the VM is powered off, the next qemu run
causes kernel panic due to a NULL pointer dereference in
irq_bypass_register_producer().
When the VM is powered off, vhost_vdpa_clean_irq() misses on calling
irq_bypass_unregister_producer() for irq 0 because of the existing check.
This leaves stale producer nodes, which are reset in
vhost_vring_call_reset() when vhost_dev_init() is invoked during the
second qemu run.
As the node member of struct irq_bypass_producer is also initialized
to zero, traversal on the producers list causes crash due to NULL
pointer dereference.
Fixes: 2cf1ba9a4d15c ("vhost_vdpa: implement IRQ offloading in vhost_vdpa")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211711
Signed-off-by: Gautam Dawar <gdawar.xilinx@xxxxxxxxx>
Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210224114845.104173-1-gdawar.xilinx@xxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vhost/vdpa.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -910,14 +910,10 @@ err:
static void vhost_vdpa_clean_irq(struct vhost_vdpa *v)
{
- struct vhost_virtqueue *vq;
int i;
- for (i = 0; i < v->nvqs; i++) {
- vq = &v->vqs[i];
- if (vq->call_ctx.producer.irq)
- irq_bypass_unregister_producer(&vq->call_ctx.producer);
- }
+ for (i = 0; i < v->nvqs; i++)
+ vhost_vdpa_unsetup_vq_irq(v, i);
}
static int vhost_vdpa_release(struct inode *inode, struct file *filep)
Patches currently in stable-queue which might be from gdawar.xilinx@xxxxxxxxx are
queue-5.10/vhost_vdpa-fix-the-missing-irq_bypass_unregister_producer-invocation.patch
