From: Haiyue Wang haiyue.wang@intel.com
commit 1f84a9450d75e08af70d9e2f2d5e1c0ac0c881d2 upstream.
The 'tail' and 'head' are 'unsigned int' type free-running count, when 'head' is overflow, the 'int i (= tail) < u32 head' will be false:
Only '- loop 0: idx = 63' result is shown, so it needs to use 'int' type to compare, it can handle the overflow correctly.
typedef uint32_t u32;
int main() { u32 tail, head; int stail, shead; int i, loop;
tail = 0xffffffff; head = 0x00000000;
for (i = tail, loop = 0; i < head; i++) { unsigned int idx = i & 63;
printf("+ loop %d: idx = %u\n", loop++, idx); }
stail = tail; shead = head; for (i = stail, loop = 0; i < shead; i++) { unsigned int idx = i & 63;
printf("- loop %d: idx = %u\n", loop++, idx); }
return 0; }
Fixes: 5cdad90de62c ("gve: Batch AQ commands for creating and destroying queues.") Signed-off-by: Haiyue Wang haiyue.wang@intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/google/gve/gve_adminq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/ethernet/google/gve/gve_adminq.c +++ b/drivers/net/ethernet/google/gve/gve_adminq.c @@ -281,7 +281,7 @@ static int gve_adminq_parse_err(struct g */ static int gve_adminq_kick_and_wait(struct gve_priv *priv) { - u32 tail, head; + int tail, head; int i;
tail = ioread32be(&priv->reg_bar0->adminq_event_counter);