#define ENOMEM      12  /* Out of memory */

#define NULL (void*)0

#define ___GFP_WAIT             0x10u
#define ___GFP_IO               0x40u
#define ___GFP_FS               0x80u
#define __GFP_WAIT      ((int)___GFP_WAIT)    /* Can wait and reschedule? */
#define __GFP_IO        ((int)___GFP_IO)      /* Can start physical IO? */
#define __GFP_FS        ((int)___GFP_FS)      /* Can call down to low-level FS? */
#define GFP_KERNEL      (__GFP_WAIT | __GFP_IO | __GFP_FS)

#define ___GFP_DMA              0x01u
#define __GFP_DMA       ((int)___GFP_DMA)
#define GFP_DMA         __GFP_DMA

static int some_int = 0;

int* __alloc_pages_nodemask(int gfp_mask)
{
#ifndef CONFIG_ZONE_DMA
  if (gfp_mask & __GFP_DMA)
    return NULL; // (4)
#endif
  return &some_int;
}

#ifdef CONFIG_EP93XX_ETH
int ep93xx_alloc_buffers()
{
  int *descs = __alloc_pages_nodemask(GFP_KERNEL | GFP_DMA); // (3)
  if (descs == NULL)
    return 1; // (5)
}

int ep93xx_open()
{
  if (ep93xx_alloc_buffers()) // (2)
    return -ENOMEM; // (6) ERROR
}
#endif

int main(void)
{
#ifdef CONFIG_EP93XX_ETH
  ep93xx_open(); // (1)
#endif
  return 0;
}

diff --git a/simple/1f758a4.c b/simple/1f758a4.c
--- a/simple/1f758a4.c
+++ b/simple/1f758a4.c
@@ -29,7 +29,7 @@
 #ifdef CONFIG_EP93XX_ETH
 int ep93xx_alloc_buffers()
 {
-  int *descs = __alloc_pages_nodemask(GFP_KERNEL | GFP_DMA); // (3)
+  int *descs = __alloc_pages_nodemask(GFP_KERNEL); // (3)
   if (descs == NULL)
     return 1; // (5)
 }

#include <errno.h>
#include <stdlib.h>

#define ___GFP_WAIT             0x10u
#define ___GFP_IO               0x40u
#define ___GFP_FS               0x80u
#define __GFP_WAIT      ((gfp_t)___GFP_WAIT)    /* Can wait and reschedule? */
#define __GFP_IO        ((gfp_t)___GFP_IO)      /* Can start physical IO? */
#define __GFP_FS        ((gfp_t)___GFP_FS)      /* Can call down to low-level FS? */
#define GFP_KERNEL      (__GFP_WAIT | __GFP_IO | __GFP_FS)

#define ___GFP_DMA              0x01u
#define __GFP_DMA       ((gfp_t)___GFP_DMA)
#define GFP_DMA         __GFP_DMA

typedef int gfp_t;

static int some_int = 0;

int main(int argc, char** argv)
{
#ifdef CONFIG_EP93XX_ETH
//  ep93xx_open();
  #ifndef CONFIG_ZONE_DMA
  if ((GFP_KERNEL | GFP_DMA) & __GFP_DMA)
    return NULL;
  #endif
  int *descs = &some_int;
  if (descs == NULL)
    return -ENOMEM; // ERROR
#endif
  return 0;
}

// ref a197b59ae6e8bee56fcef37ea2482dc08414e2ac
. call drivers/net/arm/ep93xx_eth.c:650:ep93xx_open()
. 655: if (ep93xx_alloc_buffers(ep))
.. call drivers/net/arm/ep93xx_eth.c:492:ep93xx_alloc_buffers()
.. 496: ep->descs = dma_alloc_coherent(dev, sizeof(struct ep93xx_descs), &ep->descs_dma_addr, GFP_KERNEL | GFP_DMA);
... call mm/page_alloc.c:2234:__alloc_pages_nodemask()
... [ZONE_DMA] 2251: if (WARN_ON_ONCE(gfp_mask & __GFP_DMA))
... [ZONE_DMA] 2252: return NULL;
.. 498: if (ep->descs == NULL)
.. 499: return 1;
. ERROR 656: return -ENOMEM;