diff mbox series

[v9,8/8] x86/boot/KASLR: Limit kaslr to choosing the immovable memory

Message ID 20181017102012.872-9-fanc.fnst@cn.fujitsu.com (mailing list archive)
State Not Applicable, archived
Headers show
Series x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory | expand

Commit Message

Chao Fan Oct. 17, 2018, 10:20 a.m. UTC
If CONFIG_MEMORY_HOTREMOVE enabled and the amount of immovable
memory regions is not zero. Calculate the intersection between memory
regions from e820/efi memory table and immovable memory regions.

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
---
 arch/x86/boot/compressed/kaslr.c | 72 +++++++++++++++++++++++++++-----
 1 file changed, 61 insertions(+), 11 deletions(-)

Comments

Baoquan He Oct. 18, 2018, 4:21 a.m. UTC | #1
On 10/17/18 at 06:20pm, Chao Fan wrote:
> If CONFIG_MEMORY_HOTREMOVE enabled and the amount of immovable
> memory regions is not zero. Calculate the intersection between memory

This if conditional adverbial clauses is not an complete sentence.

> regions from e820/efi memory table and immovable memory regions.
					^ get?
> 
> Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
> ---
>  arch/x86/boot/compressed/kaslr.c | 72 +++++++++++++++++++++++++++-----
>  1 file changed, 61 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
> index 0c3567bc231c..3ebb150f61eb 100644
> --- a/arch/x86/boot/compressed/kaslr.c
> +++ b/arch/x86/boot/compressed/kaslr.c
> @@ -101,6 +101,11 @@ static bool memmap_too_large;
>  /* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */
>  static unsigned long long mem_limit = ULLONG_MAX;
>  
> +#ifdef CONFIG_MEMORY_HOTREMOVE
> +/* Store the immovable memory regions */
> +extern struct mem_vector immovable_mem[MAX_NUMNODES*2];

Sorry, Chao. I may not follow your old patch change, why the length of
immovable_mem is MAX_NUMNODES*2, is there any reason or basis?

> +#endif
> +
>  
>  enum mem_avoid_index {
>  	MEM_AVOID_ZO_RANGE = 0,
> @@ -577,9 +582,9 @@ static unsigned long slots_fetch_random(void)
>  	return 0;
>  }
>  
> -static void process_mem_region(struct mem_vector *entry,
> -			       unsigned long minimum,
> -			       unsigned long image_size)
> +static void slots_count(struct mem_vector *entry,
> +			unsigned long minimum,
> +			unsigned long image_size)
>  {
>  	struct mem_vector region, overlap;
>  	unsigned long start_orig, end;
> @@ -655,6 +660,57 @@ static void process_mem_region(struct mem_vector *entry,
>  	}
>  }
>  
> +static bool process_mem_region(struct mem_vector *region,
> +			       unsigned long long minimum,
> +			       unsigned long long image_size)
> +{
> +	int i;
> +	/*
> +	 * If no immovable memory found, or MEMORY_HOTREMOVE disabled,
> +	 * walk all the regions, so use region directely.
> +	 */
> +	if (num_immovable_mem == 0) {
> +		slots_count(region, minimum, image_size);
> +
> +		if (slot_area_index == MAX_SLOT_AREA) {
> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
> +			return 1;
> +		}
> +		return 0;
> +	}
> +
> +#ifdef CONFIG_MEMORY_HOTREMOVE
> +	/*
> +	 * If immovable memory found, filter the intersection between
> +	 * immovable memory and region to slots_count.
> +	 * Otherwise, go on old code.

Could you explain more about what is the old code in otherwise case you
want to go on?

> +	 */
> +	for (i = 0; i < num_immovable_mem; i++) {
> +		struct mem_vector entry;
> +		unsigned long long start, end, entry_end, region_end;
> +
> +		if (!mem_overlaps(region, &immovable_mem[i]))
> +			continue;
> +
> +		start = immovable_mem[i].start;
> +		end = start + immovable_mem[i].size;
> +		region_end = region->start + region->size;
> +
> +		entry.start = clamp(region->start, start, end);
> +		entry_end = clamp(region_end, start, end);
> +		entry.size = entry_end - entry.start;
> +
> +		slots_count(&entry, minimum, image_size);

Obviously, your patch log only covers this place of code. About renaming
process_mem_region() to  slot_count(), and add another level of wrapper 
process_mem_region(), may also need be mentioned in patch log.

> +
> +		if (slot_area_index == MAX_SLOT_AREA) {
> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
> +			return 1;
> +		}
> +	}
> +	return 0;
> +#endif
> +}
> +
>  #ifdef CONFIG_EFI
>  /*
>   * Returns true if mirror region found (and must have been processed
> @@ -720,11 +776,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
>  
>  		region.start = md->phys_addr;
>  		region.size = md->num_pages << EFI_PAGE_SHIFT;
> -		process_mem_region(&region, minimum, image_size);
> -		if (slot_area_index == MAX_SLOT_AREA) {
> -			debug_putstr("Aborted EFI scan (slot_areas full)!\n");
> +		if (process_mem_region(&region, minimum, image_size))
>  			break;
> -		}
>  	}
>  	return true;
>  }
> @@ -751,11 +804,8 @@ static void process_e820_entries(unsigned long minimum,
>  			continue;
>  		region.start = entry->addr;
>  		region.size = entry->size;
> -		process_mem_region(&region, minimum, image_size);
> -		if (slot_area_index == MAX_SLOT_AREA) {
> -			debug_putstr("Aborted e820 scan (slot_areas full)!\n");
> +		if (process_mem_region(&region, minimum, image_size))
>  			break;
> -		}
>  	}
>  }
>  
> -- 
> 2.17.2
> 
> 
>
Chao Fan Oct. 22, 2018, 10:13 a.m. UTC | #2
On Thu, Oct 18, 2018 at 12:21:23PM +0800, Baoquan He wrote:
>On 10/17/18 at 06:20pm, Chao Fan wrote:
>> If CONFIG_MEMORY_HOTREMOVE enabled and the amount of immovable
>> memory regions is not zero. Calculate the intersection between memory
>
>This if conditional adverbial clauses is not an complete sentence.
>
>> regions from e820/efi memory table and immovable memory regions.
>					^ get?
>> 
>> Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
>> ---
>>  arch/x86/boot/compressed/kaslr.c | 72 +++++++++++++++++++++++++++-----
>>  1 file changed, 61 insertions(+), 11 deletions(-)
>> 
>> diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
>> index 0c3567bc231c..3ebb150f61eb 100644
>> --- a/arch/x86/boot/compressed/kaslr.c
>> +++ b/arch/x86/boot/compressed/kaslr.c
>> @@ -101,6 +101,11 @@ static bool memmap_too_large;
>>  /* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */
>>  static unsigned long long mem_limit = ULLONG_MAX;
>>  
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +/* Store the immovable memory regions */
>> +extern struct mem_vector immovable_mem[MAX_NUMNODES*2];
>
>Sorry, Chao. I may not follow your old patch change, why the length of
>immovable_mem is MAX_NUMNODES*2, is there any reason or basis?
>
>> +#endif
>> +
>>  
>>  enum mem_avoid_index {
>>  	MEM_AVOID_ZO_RANGE = 0,
>> @@ -577,9 +582,9 @@ static unsigned long slots_fetch_random(void)
>>  	return 0;
>>  }
>>  
>> -static void process_mem_region(struct mem_vector *entry,
>> -			       unsigned long minimum,
>> -			       unsigned long image_size)
>> +static void slots_count(struct mem_vector *entry,
>> +			unsigned long minimum,
>> +			unsigned long image_size)
>>  {
>>  	struct mem_vector region, overlap;
>>  	unsigned long start_orig, end;
>> @@ -655,6 +660,57 @@ static void process_mem_region(struct mem_vector *entry,
>>  	}
>>  }
>>  
>> +static bool process_mem_region(struct mem_vector *region,
>> +			       unsigned long long minimum,
>> +			       unsigned long long image_size)
>> +{
>> +	int i;
>> +	/*
>> +	 * If no immovable memory found, or MEMORY_HOTREMOVE disabled,
>> +	 * walk all the regions, so use region directely.
>> +	 */
>> +	if (num_immovable_mem == 0) {
>> +		slots_count(region, minimum, image_size);
>> +
>> +		if (slot_area_index == MAX_SLOT_AREA) {
>> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
>> +			return 1;
>> +		}
>> +		return 0;
>> +	}
>> +
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +	/*
>> +	 * If immovable memory found, filter the intersection between
>> +	 * immovable memory and region to slots_count.
>> +	 * Otherwise, go on old code.
>
>Could you explain more about what is the old code in otherwise case you
>want to go on?

Sure,
1. 'movable_node' not specified in cmdline.
2. CONFIG_HOT_REMOVE not difned.
3. Just one node in this machine.
>
>> +	 */
>> +	for (i = 0; i < num_immovable_mem; i++) {
>> +		struct mem_vector entry;
>> +		unsigned long long start, end, entry_end, region_end;
>> +
>> +		if (!mem_overlaps(region, &immovable_mem[i]))
>> +			continue;
>> +
>> +		start = immovable_mem[i].start;
>> +		end = start + immovable_mem[i].size;
>> +		region_end = region->start + region->size;
>> +
>> +		entry.start = clamp(region->start, start, end);
>> +		entry_end = clamp(region_end, start, end);
>> +		entry.size = entry_end - entry.start;
>> +
>> +		slots_count(&entry, minimum, image_size);
>
>Obviously, your patch log only covers this place of code. About renaming
>process_mem_region() to  slot_count(), and add another level of wrapper 
>process_mem_region(), may also need be mentioned in patch log.
>
Sorry for missing the comment.
Rename process_mem_region to slots_count to match slots_fetch_random,
and name new function as process_mem_region.

Thanks,
Chao Fan

>> +
>> +		if (slot_area_index == MAX_SLOT_AREA) {
>> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
>> +			return 1;
>> +		}
>> +	}
>> +	return 0;
>> +#endif
>> +}
>> +
>>  #ifdef CONFIG_EFI
>>  /*
>>   * Returns true if mirror region found (and must have been processed
>> @@ -720,11 +776,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
>>  
>>  		region.start = md->phys_addr;
>>  		region.size = md->num_pages << EFI_PAGE_SHIFT;
>> -		process_mem_region(&region, minimum, image_size);
>> -		if (slot_area_index == MAX_SLOT_AREA) {
>> -			debug_putstr("Aborted EFI scan (slot_areas full)!\n");
>> +		if (process_mem_region(&region, minimum, image_size))
>>  			break;
>> -		}
>>  	}
>>  	return true;
>>  }
>> @@ -751,11 +804,8 @@ static void process_e820_entries(unsigned long minimum,
>>  			continue;
>>  		region.start = entry->addr;
>>  		region.size = entry->size;
>> -		process_mem_region(&region, minimum, image_size);
>> -		if (slot_area_index == MAX_SLOT_AREA) {
>> -			debug_putstr("Aborted e820 scan (slot_areas full)!\n");
>> +		if (process_mem_region(&region, minimum, image_size))
>>  			break;
>> -		}
>>  	}
>>  }
>>  
>> -- 
>> 2.17.2
>> 
>> 
>> 
>
>
Baoquan He Oct. 22, 2018, 10:24 a.m. UTC | #3
On 10/22/18 at 06:13pm, Chao Fan wrote:
> >> +static bool process_mem_region(struct mem_vector *region,
> >> +			       unsigned long long minimum,
> >> +			       unsigned long long image_size)
> >> +{
> >> +	int i;
> >> +	/*
> >> +	 * If no immovable memory found, or MEMORY_HOTREMOVE disabled,
> >> +	 * walk all the regions, so use region directely.
> >> +	 */
> >> +	if (num_immovable_mem == 0) {
> >> +		slots_count(region, minimum, image_size);
> >> +
> >> +		if (slot_area_index == MAX_SLOT_AREA) {
> >> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
> >> +			return 1;
> >> +		}
> >> +		return 0;
> >> +	}
> >> +
> >> +#ifdef CONFIG_MEMORY_HOTREMOVE
> >> +	/*
> >> +	 * If immovable memory found, filter the intersection between
> >> +	 * immovable memory and region to slots_count.
> >> +	 * Otherwise, go on old code.
> >
> >Could you explain more about what is the old code in otherwise case you
> >want to go on?
> 
> Sure,
> 1. 'movable_node' not specified in cmdline.
> 2. CONFIG_HOT_REMOVE not difned.
> 3. Just one node in this machine.

So these cases are not covered by 'if (num_immovable_mem == 0)' code?
In thise ifdef code block, where do you handle above three cases?

Thanks
Baoquan
Chao Fan Oct. 22, 2018, 10:49 a.m. UTC | #4
On Mon, Oct 22, 2018 at 06:24:55PM +0800, Baoquan He wrote:
>On 10/22/18 at 06:13pm, Chao Fan wrote:
>> >> +static bool process_mem_region(struct mem_vector *region,
>> >> +			       unsigned long long minimum,
>> >> +			       unsigned long long image_size)
>> >> +{
>> >> +	int i;
>> >> +	/*
>> >> +	 * If no immovable memory found, or MEMORY_HOTREMOVE disabled,
>> >> +	 * walk all the regions, so use region directely.
>> >> +	 */
>> >> +	if (num_immovable_mem == 0) {
>> >> +		slots_count(region, minimum, image_size);
>> >> +
>> >> +		if (slot_area_index == MAX_SLOT_AREA) {
>> >> +			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
>> >> +			return 1;
>> >> +		}
>> >> +		return 0;
>> >> +	}
>> >> +
>> >> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> >> +	/*
>> >> +	 * If immovable memory found, filter the intersection between
>> >> +	 * immovable memory and region to slots_count.
>> >> +	 * Otherwise, go on old code.
>> >
>> >Could you explain more about what is the old code in otherwise case you
>> >want to go on?
>> 
>> Sure,
>> 1. 'movable_node' not specified in cmdline.
>> 2. CONFIG_HOT_REMOVE not difned.
>> 3. Just one node in this machine.
>
>So these cases are not covered by 'if (num_immovable_mem == 0)' code?
They are covered by 'if (num_immovable_mem == 0)' code.
>In thise ifdef code block, where do you handle above three cases?
"go on old code." means above:
+ if (num_immovable_mem == 0) {
+         slots_count(region, minimum, image_size);
+
+         if (slot_area_index == MAX_SLOT_AREA) {
+                 debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
+                 return 1;
+         }
+         return 0;
+ }

Thanks,
Chao Fan

>
>Thanks
>Baoquan
>
>
diff mbox series

Patch

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 0c3567bc231c..3ebb150f61eb 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -101,6 +101,11 @@  static bool memmap_too_large;
 /* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */
 static unsigned long long mem_limit = ULLONG_MAX;
 
+#ifdef CONFIG_MEMORY_HOTREMOVE
+/* Store the immovable memory regions */
+extern struct mem_vector immovable_mem[MAX_NUMNODES*2];
+#endif
+
 
 enum mem_avoid_index {
 	MEM_AVOID_ZO_RANGE = 0,
@@ -577,9 +582,9 @@  static unsigned long slots_fetch_random(void)
 	return 0;
 }
 
-static void process_mem_region(struct mem_vector *entry,
-			       unsigned long minimum,
-			       unsigned long image_size)
+static void slots_count(struct mem_vector *entry,
+			unsigned long minimum,
+			unsigned long image_size)
 {
 	struct mem_vector region, overlap;
 	unsigned long start_orig, end;
@@ -655,6 +660,57 @@  static void process_mem_region(struct mem_vector *entry,
 	}
 }
 
+static bool process_mem_region(struct mem_vector *region,
+			       unsigned long long minimum,
+			       unsigned long long image_size)
+{
+	int i;
+	/*
+	 * If no immovable memory found, or MEMORY_HOTREMOVE disabled,
+	 * walk all the regions, so use region directely.
+	 */
+	if (num_immovable_mem == 0) {
+		slots_count(region, minimum, image_size);
+
+		if (slot_area_index == MAX_SLOT_AREA) {
+			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
+			return 1;
+		}
+		return 0;
+	}
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+	/*
+	 * If immovable memory found, filter the intersection between
+	 * immovable memory and region to slots_count.
+	 * Otherwise, go on old code.
+	 */
+	for (i = 0; i < num_immovable_mem; i++) {
+		struct mem_vector entry;
+		unsigned long long start, end, entry_end, region_end;
+
+		if (!mem_overlaps(region, &immovable_mem[i]))
+			continue;
+
+		start = immovable_mem[i].start;
+		end = start + immovable_mem[i].size;
+		region_end = region->start + region->size;
+
+		entry.start = clamp(region->start, start, end);
+		entry_end = clamp(region_end, start, end);
+		entry.size = entry_end - entry.start;
+
+		slots_count(&entry, minimum, image_size);
+
+		if (slot_area_index == MAX_SLOT_AREA) {
+			debug_putstr("Aborted e820/efi memmap scan (slot_areas full)!\n");
+			return 1;
+		}
+	}
+	return 0;
+#endif
+}
+
 #ifdef CONFIG_EFI
 /*
  * Returns true if mirror region found (and must have been processed
@@ -720,11 +776,8 @@  process_efi_entries(unsigned long minimum, unsigned long image_size)
 
 		region.start = md->phys_addr;
 		region.size = md->num_pages << EFI_PAGE_SHIFT;
-		process_mem_region(&region, minimum, image_size);
-		if (slot_area_index == MAX_SLOT_AREA) {
-			debug_putstr("Aborted EFI scan (slot_areas full)!\n");
+		if (process_mem_region(&region, minimum, image_size))
 			break;
-		}
 	}
 	return true;
 }
@@ -751,11 +804,8 @@  static void process_e820_entries(unsigned long minimum,
 			continue;
 		region.start = entry->addr;
 		region.size = entry->size;
-		process_mem_region(&region, minimum, image_size);
-		if (slot_area_index == MAX_SLOT_AREA) {
-			debug_putstr("Aborted e820 scan (slot_areas full)!\n");
+		if (process_mem_region(&region, minimum, image_size))
 			break;
-		}
 	}
 }