From 7f08ec6e04269ce53b664761c9108b44ed2f54ab Mon Sep 17 00:00:00 2001 From: Antoine Tenart Date: Mon, 22 Mar 2021 16:43:29 +0100 Subject: [PATCH] net-sysfs: remove possible sleep from an RCU read-side critical section xps_queue_show is mostly made of an RCU read-side critical section and calls bitmap_zalloc with GFP_KERNEL in the middle of it. That is not allowed as this call may sleep and such behaviours aren't allowed in RCU read-side critical sections. Fix this by using GFP_NOWAIT instead. Fixes: 5478fcd0f483 ("net: embed nr_ids in the xps maps") Reported-by: kernel test robot Suggested-by: Matthew Wilcox Signed-off-by: Antoine Tenart Signed-off-by: David S. Miller --- net/core/net-sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 562a42fcd437e..f6197774048b6 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1378,7 +1378,7 @@ static ssize_t xps_queue_show(struct net_device *dev, unsigned int index, nr_ids = dev_maps ? dev_maps->nr_ids : (type == XPS_CPUS ? nr_cpu_ids : dev->num_rx_queues); - mask = bitmap_zalloc(nr_ids, GFP_KERNEL); + mask = bitmap_zalloc(nr_ids, GFP_NOWAIT); if (!mask) { rcu_read_unlock(); return -ENOMEM;