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authorHelge Deller <deller@gmx.de>2013-05-28 20:35:54 +0000
committerHelge Deller <deller@gmx.de>2013-06-01 14:28:35 +0200
commitae249b5fa27f9fba25aa59664d4338efc2dd2394 (patch)
parent3f108de96ba449a8df3d7e3c053bf890fee2cb95 (diff)
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>
1 files changed, 1 insertions, 4 deletions
diff --git a/arch/parisc/include/asm/mmzone.h b/arch/parisc/include/asm/mmzone.h
index 0e625ab9aae..cc50d33b7b8 100644
--- a/arch/parisc/include/asm/mmzone.h
+++ b/arch/parisc/include/asm/mmzone.h
@@ -39,17 +39,14 @@ extern unsigned char pfnnid_map[PFNNID_MAP_MAX];
static inline int pfn_to_nid(unsigned long pfn)
unsigned int i;
- unsigned char r;
if (unlikely(pfn_is_io(pfn)))
return 0;
i = pfn >> PFNNID_SHIFT;
BUG_ON(i >= ARRAY_SIZE(pfnnid_map));
- r = pfnnid_map[i];
- BUG_ON(r == 0xff);
- return (int)r;
+ return (int)pfnnid_map[i];
static inline int pfn_valid(int pfn)