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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-03 23:40:38 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-03 23:40:38 +0300
commit25e09ca52459586eb6171209635bc8b436a56d79 (patch)
tree405d1a8387cf1df44c9e42f17d83b060d42a098f
parent48b5259cf0a2b86b978da122f9459e22a2d1e8f6 (diff)
parentfe2d48b805d01e14ddb8144de01de43171eb516f (diff)
downloadlinux-25e09ca52459586eb6171209635bc8b436a56d79.tar.xz
Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar: "The main changes in this cycle were KASLR improvements for rare environments with special boot options, by Baoquan He. Also misc smaller changes/cleanups" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/debug: Extend the lower bound of crash kernel low reservations x86/boot: Remove unused copy_*_gs() functions x86/KASLR: Use the right memcpy() implementation Documentation/kernel-parameters.txt: Update 'memmap=' boot option description x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options x86/KASLR: Parse all 'memmap=' boot option entries
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt9
-rw-r--r--arch/x86/boot/compressed/cmdline.c2
-rw-r--r--arch/x86/boot/compressed/kaslr.c191
-rw-r--r--arch/x86/boot/copy.S20
-rw-r--r--arch/x86/boot/string.c8
-rw-r--r--arch/x86/kernel/setup.c2
6 files changed, 145 insertions, 87 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index f59aad5c2270..9b0b3dea6326 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2136,6 +2136,12 @@
memmap=nn[KMG]@ss[KMG]
[KNL] Force usage of a specific region of memory.
Region of memory to be used is from ss to ss+nn.
+ If @ss[KMG] is omitted, it is equivalent to mem=nn[KMG],
+ which limits max address to nn[KMG].
+ Multiple different regions can be specified,
+ comma delimited.
+ Example:
+ memmap=100M@2G,100M#3G,1G!1024G
memmap=nn[KMG]#ss[KMG]
[KNL,ACPI] Mark specific memory as ACPI data.
@@ -2148,6 +2154,9 @@
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
+ Some bootloaders may need an escape character before '$',
+ like Grub2, otherwise '$' and the following number
+ will be eaten.
memmap=nn[KMG]!ss[KMG]
[KNL,X86] Mark specific memory as protected.
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index 73ccf63b0f48..9dc1ce6ba3c0 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c
@@ -13,7 +13,7 @@ static inline char rdfs8(addr_t addr)
return *((char *)(fs + addr));
}
#include "../cmdline.c"
-static unsigned long get_cmd_line_ptr(void)
+unsigned long get_cmd_line_ptr(void)
{
unsigned long cmd_line_ptr = boot_params->hdr.cmd_line_ptr;
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 56a7e9201741..91f27ab970ef 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -9,16 +9,42 @@
* contain the entire properly aligned running kernel image.
*
*/
+
+/*
+ * isspace() in linux/ctype.h is expected by next_args() to filter
+ * out "space/lf/tab". While boot/ctype.h conflicts with linux/ctype.h,
+ * since isdigit() is implemented in both of them. Hence disable it
+ * here.
+ */
+#define BOOT_CTYPE_H
+
+/*
+ * _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)
+
#include "misc.h"
#include "error.h"
-#include "../boot.h"
+#include "../string.h"
#include <generated/compile.h>
#include <linux/module.h>
#include <linux/uts.h>
#include <linux/utsname.h>
+#include <linux/ctype.h>
#include <generated/utsrelease.h>
+/* Macros used by the included decompressor code below. */
+#define STATIC
+#include <linux/decompress/mm.h>
+
+extern unsigned long get_cmd_line_ptr(void);
+
/* Simplified build-specific string for starting entropy. */
static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION;
@@ -62,6 +88,11 @@ struct mem_vector {
static bool memmap_too_large;
+
+/* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */
+unsigned long long mem_limit = ULLONG_MAX;
+
+
enum mem_avoid_index {
MEM_AVOID_ZO_RANGE = 0,
MEM_AVOID_INITRD,
@@ -85,49 +116,14 @@ static bool mem_overlaps(struct mem_vector *one, struct mem_vector *two)
return true;
}
-/**
- * _memparse - Parse a string with mem suffixes into a number
- * @ptr: Where parse begins
- * @retptr: (output) Optional pointer to next char after parse completes
- *
- * Parses a string into a number. The number stored at @ptr is
- * potentially suffixed with K, M, G, T, P, E.
- */
-static unsigned long long _memparse(const char *ptr, char **retptr)
+char *skip_spaces(const char *str)
{
- char *endptr; /* Local pointer to end of parsed string */
-
- unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
-
- switch (*endptr) {
- case 'E':
- case 'e':
- ret <<= 10;
- case 'P':
- case 'p':
- ret <<= 10;
- case 'T':
- case 't':
- ret <<= 10;
- case 'G':
- case 'g':
- ret <<= 10;
- case 'M':
- case 'm':
- ret <<= 10;
- case 'K':
- case 'k':
- ret <<= 10;
- endptr++;
- default:
- break;
- }
-
- if (retptr)
- *retptr = endptr;
-
- return ret;
+ while (isspace(*str))
+ ++str;
+ return (char *)str;
}
+#include "../../../../lib/ctype.c"
+#include "../../../../lib/cmdline.c"
static int
parse_memmap(char *p, unsigned long long *start, unsigned long long *size)
@@ -142,40 +138,41 @@ parse_memmap(char *p, unsigned long long *start, unsigned long long *size)
return -EINVAL;
oldp = p;
- *size = _memparse(p, &p);
+ *size = memparse(p, &p);
if (p == oldp)
return -EINVAL;
switch (*p) {
- case '@':
- /* Skip this region, usable */
- *start = 0;
- *size = 0;
- return 0;
case '#':
case '$':
case '!':
- *start = _memparse(p + 1, &p);
+ *start = memparse(p + 1, &p);
+ return 0;
+ case '@':
+ /* memmap=nn@ss specifies usable region, should be skipped */
+ *size = 0;
+ /* Fall through */
+ default:
+ /*
+ * If w/o offset, only size specified, memmap=nn[KMG] has the
+ * same behaviour as mem=nn[KMG]. It limits the max address
+ * system can use. Region above the limit should be avoided.
+ */
+ *start = 0;
return 0;
}
return -EINVAL;
}
-static void mem_avoid_memmap(void)
+static void mem_avoid_memmap(char *str)
{
- char arg[128];
+ static int i;
int rc;
- int i;
- char *str;
- /* See if we have any memmap areas */
- rc = cmdline_find_option("memmap", arg, sizeof(arg));
- if (rc <= 0)
+ if (i >= MAX_MEMMAP_REGIONS)
return;
- i = 0;
- str = arg;
while (str && (i < MAX_MEMMAP_REGIONS)) {
int rc;
unsigned long long start, size;
@@ -188,9 +185,14 @@ static void mem_avoid_memmap(void)
if (rc < 0)
break;
str = k;
- /* A usable region that should not be skipped */
- if (size == 0)
+
+ if (start == 0) {
+ /* Store the specified memory limit if size > 0 */
+ if (size > 0)
+ mem_limit = size;
+
continue;
+ }
mem_avoid[MEM_AVOID_MEMMAP_BEGIN + i].start = start;
mem_avoid[MEM_AVOID_MEMMAP_BEGIN + i].size = size;
@@ -202,6 +204,57 @@ static void mem_avoid_memmap(void)
memmap_too_large = true;
}
+static int handle_mem_memmap(void)
+{
+ char *args = (char *)get_cmd_line_ptr();
+ size_t len = strlen((char *)args);
+ char *tmp_cmdline;
+ char *param, *val;
+ u64 mem_size;
+
+ if (!strstr(args, "memmap=") && !strstr(args, "mem="))
+ return 0;
+
+ tmp_cmdline = malloc(len + 1);
+ if (!tmp_cmdline )
+ error("Failed to allocate space for tmp_cmdline");
+
+ memcpy(tmp_cmdline, args, len);
+ tmp_cmdline[len] = 0;
+ args = tmp_cmdline;
+
+ /* Chew leading spaces */
+ args = skip_spaces(args);
+
+ while (*args) {
+ args = next_arg(args, &param, &val);
+ /* Stop at -- */
+ if (!val && strcmp(param, "--") == 0) {
+ warn("Only '--' specified in cmdline");
+ free(tmp_cmdline);
+ return -1;
+ }
+
+ if (!strcmp(param, "memmap")) {
+ mem_avoid_memmap(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;
+ }
+ mem_limit = mem_size;
+ }
+ }
+
+ free(tmp_cmdline);
+ return 0;
+}
+
/*
* In theory, KASLR can put the kernel anywhere in the range of [16M, 64T).
* The mem_avoid array is used to store the ranges that need to be avoided
@@ -323,7 +376,7 @@ 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 */
- mem_avoid_memmap();
+ handle_mem_memmap();
#ifdef CONFIG_X86_VERBOSE_BOOTUP
/* Make sure video RAM can be used. */
@@ -432,7 +485,8 @@ static void process_e820_entry(struct boot_e820_entry *entry,
{
struct mem_vector region, overlap;
struct slot_area slot_area;
- unsigned long start_orig;
+ unsigned long start_orig, end;
+ struct boot_e820_entry cur_entry;
/* Skip non-RAM entries. */
if (entry->type != E820_TYPE_RAM)
@@ -446,8 +500,15 @@ static void process_e820_entry(struct boot_e820_entry *entry,
if (entry->addr + entry->size < minimum)
return;
- region.start = entry->addr;
- region.size = entry->size;
+ /* Ignore entries above memory limit */
+ end = min(entry->size + entry->addr, mem_limit);
+ if (entry->addr >= end)
+ return;
+ cur_entry.addr = entry->addr;
+ cur_entry.size = end - entry->addr;
+
+ region.start = cur_entry.addr;
+ region.size = cur_entry.size;
/* Give up if slot area array is full. */
while (slot_area_index < MAX_SLOT_AREA) {
@@ -461,7 +522,7 @@ static void process_e820_entry(struct boot_e820_entry *entry,
region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN);
/* Did we raise the address above this e820 region? */
- if (region.start > entry->addr + entry->size)
+ if (region.start > cur_entry.addr + cur_entry.size)
return;
/* Reduce size by any delta from the original address. */
diff --git a/arch/x86/boot/copy.S b/arch/x86/boot/copy.S
index 1eb7d298b47d..15d9f74b0008 100644
--- a/arch/x86/boot/copy.S
+++ b/arch/x86/boot/copy.S
@@ -65,23 +65,3 @@ GLOBAL(copy_to_fs)
popw %es
retl
ENDPROC(copy_to_fs)
-
-#if 0 /* Not currently used, but can be enabled as needed */
-GLOBAL(copy_from_gs)
- pushw %ds
- pushw %gs
- popw %ds
- calll memcpy
- popw %ds
- retl
-ENDPROC(copy_from_gs)
-
-GLOBAL(copy_to_gs)
- pushw %es
- pushw %gs
- popw %es
- calll memcpy
- popw %es
- retl
-ENDPROC(copy_to_gs)
-#endif
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c
index 5457b02fc050..630e3664906b 100644
--- a/arch/x86/boot/string.c
+++ b/arch/x86/boot/string.c
@@ -122,6 +122,14 @@ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int bas
return result;
}
+long simple_strtol(const char *cp, char **endp, unsigned int base)
+{
+ if (*cp == '-')
+ return -simple_strtoull(cp + 1, endp, base);
+
+ return simple_strtoull(cp, endp, base);
+}
+
/**
* strlen - Find the length of a string
* @s: The string to be sized
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index f81823695014..65622f07e633 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -503,7 +503,7 @@ static int __init reserve_crashkernel_low(void)
return 0;
}
- low_base = memblock_find_in_range(low_size, 1ULL << 32, low_size, CRASH_ALIGN);
+ low_base = memblock_find_in_range(0, 1ULL << 32, low_size, CRASH_ALIGN);
if (!low_base) {
pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
(unsigned long)(low_size >> 20));