diff mbox series

Revert "net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}"

Message ID 20221017030947.1295426-1-yury.norov@gmail.com
State New
Headers
Series Revert "net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}" |

Commit Message

Yury Norov Oct. 17, 2022, 3:09 a.m. UTC 
  This reverts commit 854701ba4c39afae2362ba19a580c461cb183e4f.

The reverted commit makes netif_attr_test_online() network subsystems
generating warnings, and it breaks syzkaller testing.

https://syzkaller.appspot.com/bug?extid=9abe5ecc348676215427

Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
 include/linux/netdevice.h | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Comments

Michael S. Tsirkin Oct. 19, 2022, 11:49 a.m. UTC | #1 
On Sun, Oct 16, 2022 at 08:09:47PM -0700, Yury Norov wrote:
> This reverts commit 854701ba4c39afae2362ba19a580c461cb183e4f.
> 
> The reverted commit makes netif_attr_test_online() network subsystems
> generating warnings, and it breaks syzkaller testing.
> 
> https://syzkaller.appspot.com/bug?extid=9abe5ecc348676215427
> 
> Signed-off-by: Yury Norov <yury.norov@gmail.com>

Fixes: 854701ba4c39 ("net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}")
Acked-by: Michael S. Tsirkin <mst@redhat.com>

> ---
>  include/linux/netdevice.h | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index a36edb0ec199..eddf8ee270e7 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -3663,8 +3663,9 @@ static inline bool netif_attr_test_online(unsigned long j,
>  static inline unsigned int netif_attrmask_next(int n, const unsigned long *srcp,
>  					       unsigned int nr_bits)
>  {
> -	/* n is a prior cpu */
> -	cpu_max_bits_warn(n + 1, nr_bits);
> +	/* -1 is a legal arg here. */
> +	if (n != -1)
> +		cpu_max_bits_warn(n, nr_bits);
>  
>  	if (srcp)
>  		return find_next_bit(srcp, nr_bits, n + 1);
> @@ -3685,8 +3686,9 @@ static inline int netif_attrmask_next_and(int n, const unsigned long *src1p,
>  					  const unsigned long *src2p,
>  					  unsigned int nr_bits)
>  {
> -	/* n is a prior cpu */
> -	cpu_max_bits_warn(n + 1, nr_bits);
> +	/* -1 is a legal arg here. */
> +	if (n != -1)
> +		cpu_max_bits_warn(n, nr_bits);
>  
>  	if (src1p && src2p)
>  		return find_next_and_bit(src1p, src2p, nr_bits, n + 1);
> -- 
> 2.34.1
Christian Borntraeger Oct. 19, 2022, 12:16 p.m. UTC | #2 
for virtio on s390x.

Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
diff mbox series

Patch

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a36edb0ec199..eddf8ee270e7 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3663,8 +3663,9 @@  static inline bool netif_attr_test_online(unsigned long j,
 static inline unsigned int netif_attrmask_next(int n, const unsigned long *srcp,
 					       unsigned int nr_bits)
 {
-	/* n is a prior cpu */
-	cpu_max_bits_warn(n + 1, nr_bits);
+	/* -1 is a legal arg here. */
+	if (n != -1)
+		cpu_max_bits_warn(n, nr_bits);
 
 	if (srcp)
 		return find_next_bit(srcp, nr_bits, n + 1);
@@ -3685,8 +3686,9 @@  static inline int netif_attrmask_next_and(int n, const unsigned long *src1p,
 					  const unsigned long *src2p,
 					  unsigned int nr_bits)
 {
-	/* n is a prior cpu */
-	cpu_max_bits_warn(n + 1, nr_bits);
+	/* -1 is a legal arg here. */
+	if (n != -1)
+		cpu_max_bits_warn(n, nr_bits);
 
 	if (src1p && src2p)
 		return find_next_and_bit(src1p, src2p, nr_bits, n + 1);