On Tue, Feb 03, 2026 at 05:34:00PM +0100, Arnd Bergmann wrote:
From: Arnd Bergmann <[email protected]>
The gcc-16.0.1 snapshot produces a false-positive warning that turns
into a build failure with CONFIG_WERROR:
In file included from arch/x86/include/asm/string.h:6,
from net/vmw_vsock/vmci_transport.c:10:
In function 'vmci_transport_packet_init',
inlined from '__vmci_transport_send_control_pkt.constprop' at
net/vmw_vsock/vmci_transport.c:198:2:
arch/x86/include/asm/string_32.h:150:25: error: argument 2 null where non-null
expected because argument 3 is nonzero [-Werror=nonnull]
150 | #define memcpy(t, f, n) __builtin_memcpy(t, f, n)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
net/vmw_vsock/vmci_transport.c:164:17: note: in expansion of macro 'memcpy'
164 | memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
| ^~~~~~
arch/x86/include/asm/string_32.h:150:25: note: in a call to built-in function
'__builtin_memcpy'
net/vmw_vsock/vmci_transport.c:164:17: note: in expansion of macro 'memcpy'
164 | memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
| ^~~~~~
This seems relatively harmless, and it so far the only instance of this
warning I have found. The __vmci_transport_send_control_pkt function
is called either with wait=NULL or with one of the type values that
pass 'wait' into memcpy() here, but not from the same caller.
Replacing the memcpy with a struct assignment is otherwise the same
but avoids the warning.
Signed-off-by: Arnd Bergmann <[email protected]>
---
net/vmw_vsock/vmci_transport.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Not sure if it's net or net-next material, maybe net to avoid the
warning/error on v6.19 too ?
Anyway LGTM and thanks for the fix!
Reviewed-by: Stefano Garzarella <[email protected]>
diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index 00f6bbdb035a..a64522be1bad 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -161,7 +161,7 @@ vmci_transport_packet_init(struct vmci_transport_packet
*pkt,
case VMCI_TRANSPORT_PACKET_TYPE_WAITING_READ:
case VMCI_TRANSPORT_PACKET_TYPE_WAITING_WRITE:
- memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
+ pkt->u.wait = *wait;
break;
case VMCI_TRANSPORT_PACKET_TYPE_REQUEST2:
--
2.39.5
