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-next 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 also be merged in the next major kernel release
during the merge window.
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
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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
