Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Thomas Gleixner:
"Boot code updates for x86:
- Allow to skip a given amount of huge pages for address layout
randomization on the kernel command line to prevent regressions in
the huge page allocation with small memory sizes
- Various cleanups"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Use CC_SET()/CC_OUT() instead of open coding it
x86/boot/KASLR: Make local variable mem_limit static
x86/boot/KASLR: Skip specified number of 1GB huge pages when doing physical randomization (KASLR)
x86/boot/KASLR: Add two new functions for 1GB huge pages handling
diff --git a/arch/x86/boot/bitops.h b/arch/x86/boot/bitops.h
index 0d41d68..2e13824 100644
--- a/arch/x86/boot/bitops.h
+++ b/arch/x86/boot/bitops.h
@@ -17,6 +17,7 @@
#define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
#include <linux/types.h>
+#include <asm/asm.h>
static inline bool constant_test_bit(int nr, const void *addr)
{
@@ -28,7 +29,7 @@
bool v;
const u32 *p = (const u32 *)addr;
- asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr));
+ asm("btl %2,%1" CC_SET(c) : CC_OUT(c) (v) : "m" (*p), "Ir" (nr));
return v;
}
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index b87a758..3025179 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -102,7 +102,7 @@
/* 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 {
@@ -215,7 +215,36 @@
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 int handle_mem_options(void)
{
char *args = (char *)get_cmd_line_ptr();
size_t len = strlen((char *)args);
@@ -223,7 +252,8 @@
char *param, *val;
u64 mem_size;
- if (!strstr(args, "memmap=") && !strstr(args, "mem="))
+ if (!strstr(args, "memmap=") && !strstr(args, "mem=") &&
+ !strstr(args, "hugepages"))
return 0;
tmp_cmdline = malloc(len + 1);
@@ -248,6 +278,8 @@
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;
@@ -387,7 +419,7 @@
/* 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. */
@@ -466,6 +498,60 @@
}
}
+/*
+ * 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;
@@ -546,7 +632,7 @@
/* If nothing overlaps, store the region and return. */
if (!mem_avoid_overlap(®ion, &overlap)) {
- store_slot_info(®ion, image_size);
+ process_gb_huge_pages(®ion, image_size);
return;
}
@@ -556,7 +642,7 @@
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. */
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c
index 16f4912..c4428a1 100644
--- a/arch/x86/boot/string.c
+++ b/arch/x86/boot/string.c
@@ -13,6 +13,7 @@
*/
#include <linux/types.h>
+#include <asm/asm.h>
#include "ctype.h"
#include "string.h"
@@ -28,8 +29,8 @@
int memcmp(const void *s1, const void *s2, size_t len)
{
bool diff;
- asm("repe; cmpsb; setnz %0"
- : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
+ asm("repe; cmpsb" CC_SET(nz)
+ : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
return diff;
}