Fengguang is running into a warning from the buddy allocator:

swapper/0: page allocation failure: order:9, mode:0x14040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null) CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.17.0-rc1 #262 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace:

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__kmalloc+0x14b/0x180: ____cache_alloc at mm/slab.c:3127 stm_register_device+0xf3/0x5c0: stm_register_device at drivers/hwtracing/stm/core.c:695

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Which is basically a result of the stm class trying to allocate ~512kB for the dummy_stm with its default parameters. There's no reason, however, for it not to be vmalloc()ed instead, which is what this patch does.

Reported-by: Fengguang Wu fengguang.wu@intel.com Signed-off-by: Alexander Shishkin alexander.shishkin@linux.intel.com CC: stable@vger.kernel.org # v4.4+ --- drivers/hwtracing/stm/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 05386b76465e..657badb479a5 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -674,7 +674,7 @@ static void stm_device_release(struct device *dev) { struct stm_device *stm = to_stm_device(dev);

- kfree(stm); + vfree(stm); }

int stm_register_device(struct device *parent, struct stm_data *stm_data, @@ -691,7 +691,7 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, return -EINVAL;

nmasters = stm_data->sw_end - stm_data->sw_start + 1; - stm = kzalloc(sizeof(*stm) + nmasters * sizeof(void *), GFP_KERNEL); + stm = vzalloc(sizeof(*stm) + nmasters * sizeof(void *)); if (!stm) return -ENOMEM;

@@ -744,7 +744,7 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, /* matches device_initialize() above */ put_device(&stm->dev); err_free: - kfree(stm); + vfree(stm);

return err; }