From: Hao Chen <chenhao288@hisilicon.com> mainline inclusion from mainline-v5.16-rc3 commit 9c1479174870 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4M1HB CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------------------------------------- Currently, when user queries page pool info by debugfs command "cat page_pool_info", the cnt of allocated page for page pool may be incorrect because of memory inconsistency problem caused by compiler optimization. So this patch uses READ_ONCE() to read value of pages_state_hold_cnt to fix this problem. Fixes: 850bfb912a6d ("net: hns3: debugfs add support dumping page pool info") Signed-off-by: Hao Chen <chenhao288@hisilicon.com> Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Yongxin Li <liyongxin1@huawei.com> Signed-off-by: Junxin Chen <chenjunxin1@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c index fbb8a5f08222..081295bff765 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c @@ -1081,7 +1081,8 @@ static void hns3_dump_page_pool_info(struct hns3_enet_ring *ring, u32 j = 0; sprintf(result[j++], "%u", index); - sprintf(result[j++], "%u", ring->page_pool->pages_state_hold_cnt); + sprintf(result[j++], "%u", + READ_ONCE(ring->page_pool->pages_state_hold_cnt)); sprintf(result[j++], "%u", atomic_read(&ring->page_pool->pages_state_release_cnt)); sprintf(result[j++], "%u", ring->page_pool->p.pool_size); -- 2.20.1