Re: [PATCH 1/2] x86 boot: add E820_RESVD_KERN

From: Yinghai Lu
Date: Thu Jun 26 2008 - 22:22:45 EST

On Thu, Jun 26, 2008 at 2:47 AM, Yinghai Lu <yhlu.kernel@xxxxxxxxx> wrote:
> On Thu, Jun 26, 2008 at 12:48 AM, Huang, Ying <ying.huang@xxxxxxxxx> wrote:
>> On Thu, 2008-06-26 at 00:25 -0700, Yinghai Lu wrote:
>> [...]
>>> > if (pfn >= limit_pfn)
>>> > @@ -977,7 +978,7 @@ u64 __init early_reserve_e820(u64 startt
>>> > return 0;
>>> >
>>> > addr = round_down(start + size - sizet, align);
>>> > - e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
>>> > + e820_update_range(addr, sizet, E820_RAM, E820_RESVD_KERN);
>>>
>>> this line is not needed.
>>
>> Why? Memory reserved by early_rserved_e820 should not be saved during
>> hibernation? shoudl not be saved by kdump?
>>
>>> > printk(KERN_INFO "update e820 for early_reserve_e820\n");
>>> > update_e820();
>>> >
>>> > @@ -1191,6 +1192,7 @@ void __init e820_reserve_resources(void)
>>> > res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
>>> > for (i = 0; i < e820.nr_map; i++) {
>>> > switch (e820.map[i].type) {
>>> > + case E820_RESVD_KERN:
>>> > case E820_RAM: res->name = "System RAM"; break;
>>> > case E820_ACPI: res->name = "ACPI Tables"; break;
>>> > case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
>>> >
>>> > --
>>>
>>> please move reserve_setup_data() from head.c/head64.c to setup32/64.c
>>> or merged setup.c
>>
>> OK.
>>
>>> also need to change reserve_early in reserve_setup_data to
>>> e820_update_range(,,E820_RAM, E820_RESEVED_EXTRA).
>>
>> ïDoes this means reserve_early() should be replaced by
>> e820_update_range()?
>
> Yes. in your case.
>
>>
>>> calling reserve_setup_data() should around early_reserve_e820_mpc_new.
>>
>> I think reserve_xxx should be called before first find_e820_area() to
>> minimize the possibility of conflict.
> You already call e820_update_range, that could prevent find_e820_area
> to get confused.

some like the attach patch...

you still can merge parse_setup_data parse_e820_ext
also entries in parse_e820_ext is not initialized..., __copy_e820_map
will do nothing.

YH
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 7b7685b..b45255b 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -120,6 +120,7 @@ void __init e820_print_map(char *who)
(e820.map[i].addr + e820.map[i].size));
switch (e820.map[i].type) {
case E820_RAM:
+ case E820_RESERVED_KERN:
printk(KERN_CONT "(usable)\n");
break;
case E820_RESERVED:
@@ -611,7 +612,7 @@ void __init e820_mark_nosave_regions(unsigned long limit_pfn)
register_nosave_region(pfn, PFN_UP(ei->addr));

pfn = PFN_DOWN(ei->addr + ei->size);
- if (ei->type != E820_RAM)
+ if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
register_nosave_region(PFN_UP(ei->addr), pfn);

if (pfn >= limit_pfn)
@@ -1196,6 +1197,7 @@ void __init e820_reserve_resources(void)
res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
for (i = 0; i < e820.nr_map; i++) {
switch (e820.map[i].type) {
+ case E820_RESERVED_KERN:
case E820_RAM: res->name = "System RAM"; break;
case E820_ACPI: res->name = "ACPI Tables"; break;
case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
diff --git a/arch/x86/kernel/head.c b/arch/x86/kernel/head.c
index a6816be..3e66bd3 100644
--- a/arch/x86/kernel/head.c
+++ b/arch/x86/kernel/head.c
@@ -53,21 +53,3 @@ void __init reserve_ebda_region(void)
/* reserve all memory between lowmem and the 1MB mark */
reserve_early_overlap_ok(lowmem, 0x100000, "BIOS reserved");
}
-
-void __init reserve_setup_data(void)
-{
- struct setup_data *data;
- u64 pa_data;
- char buf[32];
-
- if (boot_params.hdr.version < 0x0209)
- return;
- pa_data = boot_params.hdr.setup_data;
- while (pa_data) {
- data = early_ioremap(pa_data, sizeof(*data));
- sprintf(buf, "setup data %x", data->type);
- reserve_early(pa_data, pa_data+sizeof(*data)+data->len, buf);
- pa_data = data->next;
- early_iounmap(data, sizeof(*data));
- }
-}
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index c970929..2ff9bc6 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -123,7 +123,6 @@ void __init x86_64_start_kernel(char * real_mode_data)
#endif

reserve_ebda_region();
- reserve_setup_data();

/*
* At this point everything still needed from the boot loader
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index bf528b2..e9ce633 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -389,14 +389,33 @@ static void __init parse_setup_data(void)
default:
break;
}
-#ifndef CONFIG_DEBUG_BOOT_PARAMS
- free_early(pa_data, pa_data+sizeof(*data)+data->len);
-#endif
pa_data = data->next;
early_iounmap(data, PAGE_SIZE);
}
}

+static void __init reserve_setup_data(void)
+{
+ struct setup_data *data;
+ u64 pa_data;
+ char buf[32];
+
+ if (boot_params.hdr.version < 0x0209)
+ return;
+ pa_data = boot_params.hdr.setup_data;
+ while (pa_data) {
+ data = early_ioremap(pa_data, sizeof(*data));
+ sprintf(buf, "setup data %x", data->type);
+ e820_update_range(pa_data, sizeof(*data)+data->len,
+ E820_RAM, E820_RESERVED_KERN);
+ pa_data = data->next;
+ early_iounmap(data, sizeof(*data));
+ }
+ sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ printk(KERN_INFO "extended physical RAM map:\n");
+ e820_print_map("extended");
+}
+
/*
* --------- Crashkernel reservation ------------------------------
*/
@@ -640,6 +659,8 @@ void __init setup_arch(char **cmdline_p)
*/
max_pfn = e820_end_of_ram();

+ reserve_setup_data();
+
/* preallocate 4k for mptable mpc */
early_reserve_e820_mpc_new();
/* update e820 for memory not covered by WB MTRRs */
diff --git a/include/asm-x86/bootparam.h b/include/asm-x86/bootparam.h
index 6eeba3b..ae22bdf 100644
--- a/include/asm-x86/bootparam.h
+++ b/include/asm-x86/bootparam.h
@@ -108,6 +108,4 @@ struct boot_params {
__u8 _pad9[276]; /* 0xeec */
} __attribute__((packed));

-void reserve_setup_data(void);
-
#endif /* _ASM_BOOTPARAM_H */
diff --git a/include/asm-x86/e820.h b/include/asm-x86/e820.h
index f622685..45e904f 100644
--- a/include/asm-x86/e820.h
+++ b/include/asm-x86/e820.h
@@ -44,6 +44,9 @@
#define E820_ACPI 3
#define E820_NVS 4

+/* reserved RAM used by kernel itself */
+#define E820_RESERVED_KERN 128
+
#ifndef __ASSEMBLY__
struct e820entry {
__u64 addr; /* start of memory segment */