linux_dsm_epyc7002/arch/parisc/include/asm/mmzone.h
Helge Deller ae249b5fa2 parisc: fix kernel BUG at arch/parisc/include/asm/mmzone.h:50
With CONFIG_DISCONTIGMEM=y and multiple physical memory areas,
cat /proc/kpageflags triggers this kernel bug:

kernel BUG at arch/parisc/include/asm/mmzone.h:50!
CPU: 2 PID: 7848 Comm: cat Tainted: G      D W 3.10.0-rc3-64bit #44
 IAOQ[0]: kpageflags_read0x128/0x238
 IAOQ[1]: kpageflags_read0x12c/0x238
 RP(r2): proc_reg_read0xbc/0x130
Backtrace:
 [<00000000402ca2d4>] proc_reg_read0xbc/0x130
 [<0000000040235bcc>] vfs_read0xc4/0x1d0
 [<0000000040235f0c>] SyS_read0x94/0xf0
 [<0000000040105fc0>] syscall_exit0x0/0x14

kpageflags_read() walks through the whole memory, even if some memory
areas are physically not available. So, we should better not BUG on an
unavailable pfn in pfn_to_nid() but just return the expected value -1 or
0.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-06-01 14:28:35 +02:00

63 lines
1.5 KiB
C

#ifndef _PARISC_MMZONE_H
#define _PARISC_MMZONE_H
#define MAX_PHYSMEM_RANGES 8 /* Fix the size for now (current known max is 3) */
#ifdef CONFIG_DISCONTIGMEM
extern int npmem_ranges;
struct node_map_data {
pg_data_t pg_data;
};
extern struct node_map_data node_data[];
#define NODE_DATA(nid) (&node_data[nid].pg_data)
/* We have these possible memory map layouts:
* Astro: 0-3.75, 67.75-68, 4-64
* zx1: 0-1, 257-260, 4-256
* Stretch (N-class): 0-2, 4-32, 34-xxx
*/
/* Since each 1GB can only belong to one region (node), we can create
* an index table for pfn to nid lookup; each entry in pfnnid_map
* represents 1GB, and contains the node that the memory belongs to. */
#define PFNNID_SHIFT (30 - PAGE_SHIFT)
#define PFNNID_MAP_MAX 512 /* support 512GB */
extern unsigned char pfnnid_map[PFNNID_MAP_MAX];
#ifndef CONFIG_64BIT
#define pfn_is_io(pfn) ((pfn & (0xf0000000UL >> PAGE_SHIFT)) == (0xf0000000UL >> PAGE_SHIFT))
#else
/* io can be 0xf0f0f0f0f0xxxxxx or 0xfffffffff0000000 */
#define pfn_is_io(pfn) ((pfn & (0xf000000000000000UL >> PAGE_SHIFT)) == (0xf000000000000000UL >> PAGE_SHIFT))
#endif
static inline int pfn_to_nid(unsigned long pfn)
{
unsigned int i;
if (unlikely(pfn_is_io(pfn)))
return 0;
i = pfn >> PFNNID_SHIFT;
BUG_ON(i >= ARRAY_SIZE(pfnnid_map));
return (int)pfnnid_map[i];
}
static inline int pfn_valid(int pfn)
{
int nid = pfn_to_nid(pfn);
if (nid >= 0)
return (pfn < node_end_pfn(nid));
return 0;
}
#endif
#endif /* _PARISC_MMZONE_H */