From a5593e0b329a14dea41ea173380dbf1533de2bd2 Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Thu, 9 Apr 2009 14:26:48 -0700 Subject: [PATCH] x86, PAT: Change order of cpa and free in set_memory_wb To be free of aliasing due to races, set_memory_* interfaces should follow ordering of reserving, changing memtype to UC/WC, changing memtype back to WB followed by free. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha LKML-Reference: <20090409212708.512280000@intel.com> Signed-off-by: Ingo Molnar --- arch/x86/mm/pageattr.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index d71e1b636ce6..d487eaa17bff 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -1021,15 +1021,19 @@ int _set_memory_wb(unsigned long addr, int numpages) int set_memory_wb(unsigned long addr, int numpages) { + int ret = _set_memory_wb(addr, numpages); free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); - - return _set_memory_wb(addr, numpages); + return ret; } EXPORT_SYMBOL(set_memory_wb); int set_memory_array_wb(unsigned long *addr, int addrinarray) { int i; + int ret; + + ret = change_page_attr_clear(addr, addrinarray, + __pgprot(_PAGE_CACHE_MASK), 1); for (i = 0; i < addrinarray; i++) { unsigned long start = __pa(addr[i]); @@ -1042,8 +1046,7 @@ int set_memory_array_wb(unsigned long *addr, int addrinarray) } free_memtype(start, end); } - return change_page_attr_clear(addr, addrinarray, - __pgprot(_PAGE_CACHE_MASK), 1); + return ret; } EXPORT_SYMBOL(set_memory_array_wb); -- 2.34.1