Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a5593e0b authored by venkatesh.pallipadi@intel.com's avatar venkatesh.pallipadi@intel.com Committed by Ingo Molnar
Browse files

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: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20090409212708.512280000@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 43a432b1

arch/x86/mm/pageattr.c

+7 −4
Original line number Diff line number Diff line
@@ -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);