This is a note to let you know that I've just added the patch titled Drivers: hv: vmbus: Use cpumask_var_t for on-stack cpu mask to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-testing branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will be merged to the char-misc-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From 25355252607ca288f329ee033f387764883393f6 Mon Sep 17 00:00:00 2001 From: Dexuan Cui <decui@xxxxxxxxxxxxx> Date: Sun, 23 Sep 2018 21:10:44 +0000 Subject: Drivers: hv: vmbus: Use cpumask_var_t for on-stack cpu mask MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A cpumask structure on the stack can cause a warning with CONFIG_NR_CPUS=8192 (e.g. Ubuntu 16.04 and 18.04 use this): drivers/hv//channel_mgmt.c: In function ‘init_vp_index’: drivers/hv//channel_mgmt.c:702:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=] Nowadays it looks most distros enable CONFIG_CPUMASK_OFFSTACK=y, and hence we can work around the warning by using cpumask_var_t. Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> Cc: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx> Cc: <Stable@xxxxxxxxxxxxxxx> Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hv/channel_mgmt.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 6f3e6af5e891..6277597d3d58 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -594,16 +594,18 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) bool perf_chn = vmbus_devs[dev_type].perf_device; struct vmbus_channel *primary = channel->primary_channel; int next_node; - struct cpumask available_mask; + cpumask_var_t available_mask; struct cpumask *alloced_mask; if ((vmbus_proto_version == VERSION_WS2008) || - (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) { + (vmbus_proto_version == VERSION_WIN7) || (!perf_chn) || + !alloc_cpumask_var(&available_mask, GFP_KERNEL)) { /* * Prior to win8, all channel interrupts are * delivered on cpu 0. * Also if the channel is not a performance critical * channel, bind it to cpu 0. + * In case alloc_cpumask_var() fails, bind it to cpu 0. */ channel->numa_node = 0; channel->target_cpu = 0; @@ -641,7 +643,7 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) cpumask_clear(alloced_mask); } - cpumask_xor(&available_mask, alloced_mask, + cpumask_xor(available_mask, alloced_mask, cpumask_of_node(primary->numa_node)); cur_cpu = -1; @@ -659,10 +661,10 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) } while (true) { - cur_cpu = cpumask_next(cur_cpu, &available_mask); + cur_cpu = cpumask_next(cur_cpu, available_mask); if (cur_cpu >= nr_cpu_ids) { cur_cpu = -1; - cpumask_copy(&available_mask, + cpumask_copy(available_mask, cpumask_of_node(primary->numa_node)); continue; } @@ -692,6 +694,8 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) channel->target_cpu = cur_cpu; channel->target_vp = hv_cpu_number_to_vp_number(cur_cpu); + + free_cpumask_var(available_mask); } static void vmbus_wait_for_unload(void) -- 2.19.0