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-rw-r--r--arch/x86/mm/pat/set_memory.c24
1 files changed, 14 insertions, 10 deletions
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index e9b448d1b1b70f..10288040404635 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -755,10 +755,14 @@ pmd_t *lookup_pmd_address(unsigned long address)
* areas on 32-bit NUMA systems. The percpu areas can
* end up in this kind of memory, for instance.
*
- * This could be optimized, but it is only intended to be
- * used at initialization time, and keeping it
- * unoptimized should increase the testing coverage for
- * the more obscure platforms.
+ * Note that as long as the PTEs are well-formed with correct PFNs, this
+ * works without checking the PRESENT bit in the leaf PTE. This is unlike
+ * the similar vmalloc_to_page() and derivatives. Callers may depend on
+ * this behavior.
+ *
+ * This could be optimized, but it is only used in paths that are not perf
+ * sensitive, and keeping it unoptimized should increase the testing coverage
+ * for the more obscure platforms.
*/
phys_addr_t slow_virt_to_phys(void *__virt_addr)
{
@@ -2041,17 +2045,12 @@ int set_mce_nospec(unsigned long pfn)
return rc;
}
-static int set_memory_p(unsigned long *addr, int numpages)
-{
- return change_page_attr_set(addr, numpages, __pgprot(_PAGE_PRESENT), 0);
-}
-
/* Restore full speculative operation to the pfn. */
int clear_mce_nospec(unsigned long pfn)
{
unsigned long addr = (unsigned long) pfn_to_kaddr(pfn);
- return set_memory_p(&addr, 1);
+ return set_memory_p(addr, 1);
}
EXPORT_SYMBOL_GPL(clear_mce_nospec);
#endif /* CONFIG_X86_64 */
@@ -2104,6 +2103,11 @@ int set_memory_np_noalias(unsigned long addr, int numpages)
CPA_NO_CHECK_ALIAS, NULL);
}
+int set_memory_p(unsigned long addr, int numpages)
+{
+ return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
+}
+
int set_memory_4k(unsigned long addr, int numpages)
{
return change_page_attr_set_clr(&addr, numpages, __pgprot(0),