From 43163f4c30f94d2103c948a247cdf2cda5068ca7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 20 Jun 2025 13:33:26 +0200 Subject: [PATCH] RDMA/core: reduce stack using in nldev_stat_get_doit() In the s390 defconfig, gcc-10 and earlier end up inlining three functions into nldev_stat_get_doit(), and each of them uses some 600 bytes of stack. The result is a function with an overly large stack frame and a warning: drivers/infiniband/core/nldev.c:2466:1: error: the frame size of 1720 bytes is larger than 1280 bytes [-Werror=frame-larger-than=] Mark the three functions noinline_for_stack to prevent this, ensuring that only one copy of the nlattr array is on the stack of each function. Signed-off-by: Arnd Bergmann Link: https://patch.msgid.link/20250620113335.3776965-1-arnd@kernel.org Signed-off-by: Leon Romanovsky --- drivers/infiniband/core/nldev.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c index a872643e8039f..e9b7a64192913 100644 --- a/drivers/infiniband/core/nldev.c +++ b/drivers/infiniband/core/nldev.c @@ -1469,10 +1469,11 @@ static const struct nldev_fill_res_entry fill_entries[RDMA_RESTRACK_MAX] = { }; -static int res_get_common_doit(struct sk_buff *skb, struct nlmsghdr *nlh, - struct netlink_ext_ack *extack, - enum rdma_restrack_type res_type, - res_fill_func_t fill_func) +static noinline_for_stack int +res_get_common_doit(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack, + enum rdma_restrack_type res_type, + res_fill_func_t fill_func) { const struct nldev_fill_res_entry *fe = &fill_entries[res_type]; struct nlattr *tb[RDMA_NLDEV_ATTR_MAX]; @@ -2263,10 +2264,10 @@ err: return ret; } -static int stat_get_doit_default_counter(struct sk_buff *skb, - struct nlmsghdr *nlh, - struct netlink_ext_ack *extack, - struct nlattr *tb[]) +static noinline_for_stack int +stat_get_doit_default_counter(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack, + struct nlattr *tb[]) { struct rdma_hw_stats *stats; struct nlattr *table_attr; @@ -2356,8 +2357,9 @@ err: return ret; } -static int stat_get_doit_qp(struct sk_buff *skb, struct nlmsghdr *nlh, - struct netlink_ext_ack *extack, struct nlattr *tb[]) +static noinline_for_stack int +stat_get_doit_qp(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack, struct nlattr *tb[]) { static enum rdma_nl_counter_mode mode; -- 2.47.2