diff options
| -rw-r--r-- | arch/x86/include/asm/page.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h index 625c3f0e741a..8ca82839288a 100644 --- a/arch/x86/include/asm/page.h +++ b/arch/x86/include/asm/page.h @@ -37,6 +37,13 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr, #define __pa_nodebug(x) __phys_addr_nodebug((unsigned long)(x)) /* __pa_symbol should be used for C visible symbols. This seems to be the official gcc blessed way to do such arithmetic. */ +/* + * We need __phys_reloc_hide() here because gcc may assume that there is no + * overflow during __pa() calculation and can optimize it unexpectedly. + * Newer versions of gcc provide -fno-strict-overflow switch to handle this + * case properly. Once all supported versions of gcc understand it, we can + * remove this Voodoo magic stuff. (i.e. once gcc3.x is deprecated) + */ #define __pa_symbol(x) __pa(__phys_reloc_hide((unsigned long)(x))) #define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET)) |