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Diffstat (limited to 'arch/x86/boot/compressed/kaslr.c')
-rw-r--r--arch/x86/boot/compressed/kaslr.c136
1 files changed, 117 insertions, 19 deletions
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 8199a6187251..9ed9709d9947 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -23,11 +23,8 @@
* _ctype[] in lib/ctype.c is needed by isspace() of linux/ctype.h.
* While both lib/ctype.c and lib/cmdline.c will bring EXPORT_SYMBOL
* which is meaningless and will cause compiling error in some cases.
- * So do not include linux/export.h and define EXPORT_SYMBOL(sym)
- * as empty.
*/
-#define _LINUX_EXPORT_H
-#define EXPORT_SYMBOL(sym)
+#define __DISABLE_EXPORTS
#include "misc.h"
#include "error.h"
@@ -46,8 +43,17 @@
#define STATIC
#include <linux/decompress/mm.h>
+#ifdef CONFIG_X86_5LEVEL
+unsigned int __pgtable_l5_enabled;
+unsigned int pgdir_shift __ro_after_init = 39;
+unsigned int ptrs_per_p4d __ro_after_init = 1;
+#endif
+
extern unsigned long get_cmd_line_ptr(void);
+/* Used by PAGE_KERN* macros: */
+pteval_t __default_kernel_pte_mask __read_mostly = ~0;
+
/* Simplified build-specific string for starting entropy. */
static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION;
@@ -93,7 +99,7 @@ static bool memmap_too_large;
/* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */
-unsigned long long mem_limit = ULLONG_MAX;
+static unsigned long long mem_limit = ULLONG_MAX;
enum mem_avoid_index {
@@ -206,7 +212,36 @@ static void mem_avoid_memmap(char *str)
memmap_too_large = true;
}
-static int handle_mem_memmap(void)
+/* Store the number of 1GB huge pages which users specified: */
+static unsigned long max_gb_huge_pages;
+
+static void parse_gb_huge_pages(char *param, char *val)
+{
+ static bool gbpage_sz;
+ char *p;
+
+ if (!strcmp(param, "hugepagesz")) {
+ p = val;
+ if (memparse(p, &p) != PUD_SIZE) {
+ gbpage_sz = false;
+ return;
+ }
+
+ if (gbpage_sz)
+ warn("Repeatedly set hugeTLB page size of 1G!\n");
+ gbpage_sz = true;
+ return;
+ }
+
+ if (!strcmp(param, "hugepages") && gbpage_sz) {
+ p = val;
+ max_gb_huge_pages = simple_strtoull(p, &p, 0);
+ return;
+ }
+}
+
+
+static void handle_mem_options(void)
{
char *args = (char *)get_cmd_line_ptr();
size_t len = strlen((char *)args);
@@ -214,8 +249,9 @@ static int handle_mem_memmap(void)
char *param, *val;
u64 mem_size;
- if (!strstr(args, "memmap=") && !strstr(args, "mem="))
- return 0;
+ if (!strstr(args, "memmap=") && !strstr(args, "mem=") &&
+ !strstr(args, "hugepages"))
+ return;
tmp_cmdline = malloc(len + 1);
if (!tmp_cmdline)
@@ -233,28 +269,29 @@ static int handle_mem_memmap(void)
/* Stop at -- */
if (!val && strcmp(param, "--") == 0) {
warn("Only '--' specified in cmdline");
- free(tmp_cmdline);
- return -1;
+ goto out;
}
if (!strcmp(param, "memmap")) {
mem_avoid_memmap(val);
+ } else if (strstr(param, "hugepages")) {
+ parse_gb_huge_pages(param, val);
} else if (!strcmp(param, "mem")) {
char *p = val;
if (!strcmp(p, "nopentium"))
continue;
mem_size = memparse(p, &p);
- if (mem_size == 0) {
- free(tmp_cmdline);
- return -EINVAL;
- }
+ if (mem_size == 0)
+ goto out;
+
mem_limit = mem_size;
}
}
+out:
free(tmp_cmdline);
- return 0;
+ return;
}
/*
@@ -378,7 +415,7 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size,
/* We don't need to set a mapping for setup_data. */
/* Mark the memmap regions we need to avoid */
- handle_mem_memmap();
+ handle_mem_options();
#ifdef CONFIG_X86_VERBOSE_BOOTUP
/* Make sure video RAM can be used. */
@@ -457,6 +494,60 @@ static void store_slot_info(struct mem_vector *region, unsigned long image_size)
}
}
+/*
+ * Skip as many 1GB huge pages as possible in the passed region
+ * according to the number which users specified:
+ */
+static void
+process_gb_huge_pages(struct mem_vector *region, unsigned long image_size)
+{
+ unsigned long addr, size = 0;
+ struct mem_vector tmp;
+ int i = 0;
+
+ if (!max_gb_huge_pages) {
+ store_slot_info(region, image_size);
+ return;
+ }
+
+ addr = ALIGN(region->start, PUD_SIZE);
+ /* Did we raise the address above the passed in memory entry? */
+ if (addr < region->start + region->size)
+ size = region->size - (addr - region->start);
+
+ /* Check how many 1GB huge pages can be filtered out: */
+ while (size > PUD_SIZE && max_gb_huge_pages) {
+ size -= PUD_SIZE;
+ max_gb_huge_pages--;
+ i++;
+ }
+
+ /* No good 1GB huge pages found: */
+ if (!i) {
+ store_slot_info(region, image_size);
+ return;
+ }
+
+ /*
+ * Skip those 'i'*1GB good huge pages, and continue checking and
+ * processing the remaining head or tail part of the passed region
+ * if available.
+ */
+
+ if (addr >= region->start + image_size) {
+ tmp.start = region->start;
+ tmp.size = addr - region->start;
+ store_slot_info(&tmp, image_size);
+ }
+
+ size = region->size - (addr - region->start) - i * PUD_SIZE;
+ if (size >= image_size) {
+ tmp.start = addr + i * PUD_SIZE;
+ tmp.size = size;
+ store_slot_info(&tmp, image_size);
+ }
+}
+
static unsigned long slots_fetch_random(void)
{
unsigned long slot;
@@ -486,7 +577,6 @@ static void process_mem_region(struct mem_vector *entry,
unsigned long image_size)
{
struct mem_vector region, overlap;
- struct slot_area slot_area;
unsigned long start_orig, end;
struct mem_vector cur_entry;
@@ -537,7 +627,7 @@ static void process_mem_region(struct mem_vector *entry,
/* If nothing overlaps, store the region and return. */
if (!mem_avoid_overlap(&region, &overlap)) {
- store_slot_info(&region, image_size);
+ process_gb_huge_pages(&region, image_size);
return;
}
@@ -547,7 +637,7 @@ static void process_mem_region(struct mem_vector *entry,
beginning.start = region.start;
beginning.size = overlap.start - region.start;
- store_slot_info(&beginning, image_size);
+ process_gb_huge_pages(&beginning, image_size);
}
/* Return if overlap extends to or past end of region. */
@@ -723,6 +813,14 @@ void choose_random_location(unsigned long input,
return;
}
+#ifdef CONFIG_X86_5LEVEL
+ if (__read_cr4() & X86_CR4_LA57) {
+ __pgtable_l5_enabled = 1;
+ pgdir_shift = 48;
+ ptrs_per_p4d = 512;
+ }
+#endif
+
boot_params->hdr.loadflags |= KASLR_FLAG;
/* Prepare to add new identity pagetables on demand. */