drivers/gpu/drm/amd/amdkfd: use in_compat_syscall to check open() caller type

amdkfd wants to know syscall type, not task type.  Check directly.

Unfortunately, amdkfd is making nasty assumptions that a process'
bitness is a well-defined constant thing.  This isn't the case on x86.
I don't know how much this matters, but this patch has no effect on
generated code on x86, so amdkfd is equally broken with and without this
patch.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/gpu/drm/amd/amdkfd/kfd_chardev.c

@@ -107,7 +107,7 @@ static int kfd_open(struct inode *inode, struct file *filep)
 	if (iminor(inode) != 0)
 		return -ENODEV;
 
-	is_32bit_user_mode = is_compat_task();
+	is_32bit_user_mode = in_compat_syscall();
 
 	if (is_32bit_user_mode == true) {
 		dev_warn(kfd_device,

drivers/gpu/drm/amd/amdkfd/kfd_process.c

@@ -311,7 +311,7 @@ static struct kfd_process *create_process(const struct task_struct *thread)
 		goto err_process_pqm_init;
 
 	/* init process apertures*/
-	process->is_32bit_user_mode = is_compat_task();
+	process->is_32bit_user_mode = in_compat_syscall();
 	if (kfd_init_apertures(process) != 0)
 		goto err_init_apretures;