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authorLinus Torvalds <torvalds@linux-foundation.org>2010-10-21 13:06:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-10-21 13:06:49 -0700
commit781c5a67f152c17c3e4a9ed9647f8c0be6ea5ae9 (patch)
tree5cba2f98482e4612e4daf8e57e4e50a24a273fe9 /arch/x86/kernel/setup.c
parente990c77d06dbacc8e5c5edd2c4a1005d318a4fa6 (diff)
parent9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380 (diff)
Merge branch 'x86-bios-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-bios-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, bios: Make the x86 early memory reservation a kernel option x86, bios: By default, reserve the low 64K for all BIOSes
Diffstat (limited to 'arch/x86/kernel/setup.c')
-rw-r--r--arch/x86/kernel/setup.c106
1 files changed, 30 insertions, 76 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index df770ad99b3..6154701a5fd 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -619,79 +619,7 @@ static __init void reserve_ibft_region(void)
reserve_early_overlap_ok(addr, addr + size, "ibft");
}
-#ifdef CONFIG_X86_RESERVE_LOW_64K
-static int __init dmi_low_memory_corruption(const struct dmi_system_id *d)
-{
- printk(KERN_NOTICE
- "%s detected: BIOS may corrupt low RAM, working around it.\n",
- d->ident);
-
- e820_update_range(0, 0x10000, E820_RAM, E820_RESERVED);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
-
- return 0;
-}
-#endif
-
-/* List of systems that have known low memory corruption BIOS problems */
-static struct dmi_system_id __initdata bad_bios_dmi_table[] = {
-#ifdef CONFIG_X86_RESERVE_LOW_64K
- {
- .callback = dmi_low_memory_corruption,
- .ident = "AMI BIOS",
- .matches = {
- DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
- },
- },
- {
- .callback = dmi_low_memory_corruption,
- .ident = "Phoenix BIOS",
- .matches = {
- DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies"),
- },
- },
- {
- .callback = dmi_low_memory_corruption,
- .ident = "Phoenix/MSC BIOS",
- .matches = {
- DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix/MSC"),
- },
- },
- /*
- * AMI BIOS with low memory corruption was found on Intel DG45ID and
- * DG45FC boards.
- * It has a different DMI_BIOS_VENDOR = "Intel Corp.", for now we will
- * match only DMI_BOARD_NAME and see if there is more bad products
- * with this vendor.
- */
- {
- .callback = dmi_low_memory_corruption,
- .ident = "AMI BIOS",
- .matches = {
- DMI_MATCH(DMI_BOARD_NAME, "DG45ID"),
- },
- },
- {
- .callback = dmi_low_memory_corruption,
- .ident = "AMI BIOS",
- .matches = {
- DMI_MATCH(DMI_BOARD_NAME, "DG45FC"),
- },
- },
- /*
- * The Dell Inspiron Mini 1012 has DMI_BIOS_VENDOR = "Dell Inc.", so
- * match on the product name.
- */
- {
- .callback = dmi_low_memory_corruption,
- .ident = "Phoenix BIOS",
- .matches = {
- DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1012"),
- },
- },
-#endif
- {}
-};
+static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
static void __init trim_bios_range(void)
{
@@ -699,8 +627,14 @@ static void __init trim_bios_range(void)
* A special case is the first 4Kb of memory;
* This is a BIOS owned area, not kernel ram, but generally
* not listed as such in the E820 table.
+ *
+ * This typically reserves additional memory (64KiB by default)
+ * since some BIOSes are known to corrupt low memory. See the
+ * Kconfig help text for X86_RESERVE_LOW.
*/
- e820_update_range(0, PAGE_SIZE, E820_RAM, E820_RESERVED);
+ e820_update_range(0, ALIGN(reserve_low, PAGE_SIZE),
+ E820_RAM, E820_RESERVED);
+
/*
* special case: Some BIOSen report the PC BIOS
* area (640->1Mb) as ram even though it is not.
@@ -710,6 +644,28 @@ static void __init trim_bios_range(void)
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
}
+static int __init parse_reservelow(char *p)
+{
+ unsigned long long size;
+
+ if (!p)
+ return -EINVAL;
+
+ size = memparse(p, &p);
+
+ if (size < 4096)
+ size = 4096;
+
+ if (size > 640*1024)
+ size = 640*1024;
+
+ reserve_low = size;
+
+ return 0;
+}
+
+early_param("reservelow", parse_reservelow);
+
/*
* Determine if we were loaded by an EFI loader. If so, then we have also been
* passed the efi memmap, systab, etc., so we should use these data structures
@@ -865,8 +821,6 @@ void __init setup_arch(char **cmdline_p)
dmi_scan_machine();
- dmi_check_system(bad_bios_dmi_table);
-
/*
* VMware detection requires dmi to be available, so this
* needs to be done after dmi_scan_machine, for the BP.