Commit 8c1e2162 authored May 18, 2017 by Junaid Shahid Committed by Mike Snitzer May 22, 2017

dm ioctl: restore __GFP_HIGH in copy_params()



Commit d224e938 ("drivers/md/dm-ioctl.c: use kvmalloc rather than
opencoded variant") left out the __GFP_HIGH flag when converting from
__vmalloc to kvmalloc.  This can cause the DM ioctl to fail in some low
memory situations where it wouldn't have failed earlier.  Add __GFP_HIGH
back to avoid any potential regression.

Fixes: d224e938 ("drivers/md/dm-ioctl.c: use kvmalloc rather than opencoded variant")
Signed-off-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

parent 702a6204

drivers/md/dm-ioctl.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -1710,12 +1710,13 @@ static int copy_params(struct dm_ioctl __user user, struct dm_ioctl param_kern
		}

		/*
		* Try to avoid low memory issues when a device is suspended.
		* Use __GFP_HIGH to avoid low memory issues when a device is
		* suspended and the ioctl is needed to resume it.
		* Use kmalloc() rather than vmalloc() when we can.
		*/
		dmi = NULL;
		noio_flag = memalloc_noio_save();
		dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL);
		dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL \| __GFP_HIGH);
		memalloc_noio_restore(noio_flag);

		if (!dmi) {

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