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Diffstat (limited to 'arch/x86/mm/pageattr.c')
-rw-r--r--arch/x86/mm/pageattr.c80
1 files changed, 69 insertions, 11 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 1d4eb93d333..532e7933d60 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -6,13 +6,13 @@
#include <linux/bootmem.h>
#include <linux/module.h>
#include <linux/sched.h>
-#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/pfn.h>
#include <linux/percpu.h>
+#include <linux/gfp.h>
#include <asm/e820.h>
#include <asm/processor.h>
@@ -291,8 +291,29 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
*/
if (kernel_set_to_readonly &&
within(address, (unsigned long)_text,
- (unsigned long)__end_rodata_hpage_align))
- pgprot_val(forbidden) |= _PAGE_RW;
+ (unsigned long)__end_rodata_hpage_align)) {
+ unsigned int level;
+
+ /*
+ * Don't enforce the !RW mapping for the kernel text mapping,
+ * if the current mapping is already using small page mapping.
+ * No need to work hard to preserve large page mappings in this
+ * case.
+ *
+ * This also fixes the Linux Xen paravirt guest boot failure
+ * (because of unexpected read-only mappings for kernel identity
+ * mappings). In this paravirt guest case, the kernel text
+ * mapping and the kernel identity mapping share the same
+ * page-table pages. Thus we can't really use different
+ * protections for the kernel text and identity mappings. Also,
+ * these shared mappings are made of small page mappings.
+ * Thus this don't enforce !RW mapping for small page kernel
+ * text mapping logic will help Linux Xen parvirt guest boot
+ * aswell.
+ */
+ if (lookup_address(address, &level) && (level != PG_LEVEL_4K))
+ pgprot_val(forbidden) |= _PAGE_RW;
+ }
#endif
prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden));
@@ -976,7 +997,8 @@ out_err:
}
EXPORT_SYMBOL(set_memory_uc);
-int set_memory_array_uc(unsigned long *addr, int addrinarray)
+int _set_memory_array(unsigned long *addr, int addrinarray,
+ unsigned long new_type)
{
int i, j;
int ret;
@@ -986,13 +1008,19 @@ int set_memory_array_uc(unsigned long *addr, int addrinarray)
*/
for (i = 0; i < addrinarray; i++) {
ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE,
- _PAGE_CACHE_UC_MINUS, NULL);
+ new_type, NULL);
if (ret)
goto out_free;
}
ret = change_page_attr_set(addr, addrinarray,
__pgprot(_PAGE_CACHE_UC_MINUS), 1);
+
+ if (!ret && new_type == _PAGE_CACHE_WC)
+ ret = change_page_attr_set_clr(addr, addrinarray,
+ __pgprot(_PAGE_CACHE_WC),
+ __pgprot(_PAGE_CACHE_MASK),
+ 0, CPA_ARRAY, NULL);
if (ret)
goto out_free;
@@ -1004,8 +1032,19 @@ out_free:
return ret;
}
+
+int set_memory_array_uc(unsigned long *addr, int addrinarray)
+{
+ return _set_memory_array(addr, addrinarray, _PAGE_CACHE_UC_MINUS);
+}
EXPORT_SYMBOL(set_memory_array_uc);
+int set_memory_array_wc(unsigned long *addr, int addrinarray)
+{
+ return _set_memory_array(addr, addrinarray, _PAGE_CACHE_WC);
+}
+EXPORT_SYMBOL(set_memory_array_wc);
+
int _set_memory_wc(unsigned long addr, int numpages)
{
int ret;
@@ -1132,26 +1171,34 @@ int set_pages_uc(struct page *page, int numpages)
}
EXPORT_SYMBOL(set_pages_uc);
-int set_pages_array_uc(struct page **pages, int addrinarray)
+static int _set_pages_array(struct page **pages, int addrinarray,
+ unsigned long new_type)
{
unsigned long start;
unsigned long end;
int i;
int free_idx;
+ int ret;
for (i = 0; i < addrinarray; i++) {
if (PageHighMem(pages[i]))
continue;
start = page_to_pfn(pages[i]) << PAGE_SHIFT;
end = start + PAGE_SIZE;
- if (reserve_memtype(start, end, _PAGE_CACHE_UC_MINUS, NULL))
+ if (reserve_memtype(start, end, new_type, NULL))
goto err_out;
}
- if (cpa_set_pages_array(pages, addrinarray,
- __pgprot(_PAGE_CACHE_UC_MINUS)) == 0) {
- return 0; /* Success */
- }
+ ret = cpa_set_pages_array(pages, addrinarray,
+ __pgprot(_PAGE_CACHE_UC_MINUS));
+ if (!ret && new_type == _PAGE_CACHE_WC)
+ ret = change_page_attr_set_clr(NULL, addrinarray,
+ __pgprot(_PAGE_CACHE_WC),
+ __pgprot(_PAGE_CACHE_MASK),
+ 0, CPA_PAGES_ARRAY, pages);
+ if (ret)
+ goto err_out;
+ return 0; /* Success */
err_out:
free_idx = i;
for (i = 0; i < free_idx; i++) {
@@ -1163,8 +1210,19 @@ err_out:
}
return -EINVAL;
}
+
+int set_pages_array_uc(struct page **pages, int addrinarray)
+{
+ return _set_pages_array(pages, addrinarray, _PAGE_CACHE_UC_MINUS);
+}
EXPORT_SYMBOL(set_pages_array_uc);
+int set_pages_array_wc(struct page **pages, int addrinarray)
+{
+ return _set_pages_array(pages, addrinarray, _PAGE_CACHE_WC);
+}
+EXPORT_SYMBOL(set_pages_array_wc);
+
int set_pages_wb(struct page *page, int numpages)
{
unsigned long addr = (unsigned long)page_address(page);