From 278d3ba61563ceed3cb248383ced19e14ec7bc1f Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Thu, 25 Aug 2022 13:36:45 +0200 Subject: net: Use u64_stats_fetch_begin_irq() for stats fetch. On 32bit-UP u64_stats_fetch_begin() disables only preemption. If the reader is in preemptible context and the writer side (u64_stats_update_begin*()) runs in an interrupt context (IRQ or softirq) then the writer can update the stats during the read operation. This update remains undetected. Use u64_stats_fetch_begin_irq() to ensure the stats fetch on 32bit-UP are not interrupted by a writer. 32bit-SMP remains unaffected by this change. Cc: "David S. Miller" Cc: Catherine Sullivan Cc: David Awogbemila Cc: Dimitris Michailidis Cc: Eric Dumazet Cc: Hans Ulli Kroll Cc: Jakub Kicinski Cc: Jeroen de Borst Cc: Johannes Berg Cc: Linus Walleij Cc: Paolo Abeni Cc: Simon Horman Cc: linux-arm-kernel@lists.infradead.org Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Cc: oss-drivers@corigine.com Cc: stable@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- drivers/net/netdevsim/netdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index e470e3398abc..9a1a5b203624 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -67,10 +67,10 @@ nsim_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) unsigned int start; do { - start = u64_stats_fetch_begin(&ns->syncp); + start = u64_stats_fetch_begin_irq(&ns->syncp); stats->tx_bytes = ns->tx_bytes; stats->tx_packets = ns->tx_packets; - } while (u64_stats_fetch_retry(&ns->syncp, start)); + } while (u64_stats_fetch_retry_irq(&ns->syncp, start)); } static int -- cgit v1.2.3 From 34513ada53eb3e3f711250d8dbc2de4de493d510 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Fri, 9 Sep 2022 18:38:30 +0300 Subject: netdevsim: Fix hwstats debugfs file permissions The hwstats debugfs files are only writeable, but they are created with read and write permissions, causing certain selftests to fail [1]. Fix by creating the files with write permission only. [1] # ./test_offload.py Test destruction of generic XDP... Traceback (most recent call last): File "/home/idosch/code/linux/tools/testing/selftests/bpf/./test_offload.py", line 810, in simdev = NetdevSimDev() [...] Exception: Command failed: cat /sys/kernel/debug/netdevsim/netdevsim0//ports/0/dev/hwstats/l3/disable_ifindex cat: /sys/kernel/debug/netdevsim/netdevsim0//ports/0/dev/hwstats/l3/disable_ifindex: Invalid argument Fixes: 1a6d7ae7d63c ("netdevsim: Introduce support for L3 offload xstats") Reported-by: Jie2x Zhou Tested-by: Jie2x Zhou Signed-off-by: Ido Schimmel Reviewed-by: Petr Machata Link: https://lore.kernel.org/r/20220909153830.3732504-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/hwstats.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/hwstats.c b/drivers/net/netdevsim/hwstats.c index 605a38e16db0..0e58aa7f0374 100644 --- a/drivers/net/netdevsim/hwstats.c +++ b/drivers/net/netdevsim/hwstats.c @@ -433,11 +433,11 @@ int nsim_dev_hwstats_init(struct nsim_dev *nsim_dev) goto err_remove_hwstats_recursive; } - debugfs_create_file("enable_ifindex", 0600, hwstats->l3_ddir, hwstats, + debugfs_create_file("enable_ifindex", 0200, hwstats->l3_ddir, hwstats, &nsim_dev_hwstats_l3_enable_fops.fops); - debugfs_create_file("disable_ifindex", 0600, hwstats->l3_ddir, hwstats, + debugfs_create_file("disable_ifindex", 0200, hwstats->l3_ddir, hwstats, &nsim_dev_hwstats_l3_disable_fops.fops); - debugfs_create_file("fail_next_enable", 0600, hwstats->l3_ddir, hwstats, + debugfs_create_file("fail_next_enable", 0200, hwstats->l3_ddir, hwstats, &nsim_dev_hwstats_l3_fail_fops.fops); INIT_DELAYED_WORK(&hwstats->traffic_dw, -- cgit v1.2.3