2020-09-06 19:34:47

by Randy Dunlap

[permalink] [raw]
Subject: [PATCH] <linux/page-isolation.h>: provide stubs for MEMORY_ISOLATION not set (for Microblaze)

From: Randy Dunlap <[email protected]>

Fix build errors in Microblaze when CONFIG_MEMORY_ISOLATION is not
set/enabled by adding stubs for 3 missing functions.

Fixes these build errors:

gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: mm/page_alloc.o: in function `alloc_contig_range':
(.text+0xa0c0): undefined reference to `start_isolate_page_range'
gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa2bc): undefined reference to `test_pages_isolated'
gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa378): undefined reference to `undo_isolate_page_range'

Fixes: 0815f3d81d76 ("mm: page_isolation: MIGRATE_CMA isolation functions added") # v3.10
Fixes: b023f46813cd ("memory-hotplug: skip HWPoisoned page when offlining pages") # v3.10
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Randy Dunlap <[email protected]>
Cc: Michal Nazarewicz <[email protected]>
Cc: Wen Congyang <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: [email protected]
---
include/linux/page-isolation.h | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

--- linux-next-20200903.orig/include/linux/page-isolation.h
+++ linux-next-20200903/include/linux/page-isolation.h
@@ -28,6 +28,22 @@ static inline bool is_migrate_isolate(in
{
return false;
}
+static inline int test_pages_isolated(unsigned long start_pfn,
+ unsigned long end_pfn, int isol_flags)
+{
+ return 0;
+}
+static inline int
+start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
+ unsigned migratetype, int flags)
+{
+ return 0;
+}
+static inline void
+undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
+ unsigned migratetype)
+{
+}
#endif

#define MEMORY_OFFLINE 0x1



2020-09-07 07:07:00

by Mike Rapoport

[permalink] [raw]
Subject: Re: [PATCH] <linux/page-isolation.h>: provide stubs for MEMORY_ISOLATION not set (for Microblaze)

Hi Randy,

On Sun, Sep 06, 2020 at 12:33:08PM -0700, Randy Dunlap wrote:
> From: Randy Dunlap <[email protected]>
>
> Fix build errors in Microblaze when CONFIG_MEMORY_ISOLATION is not
> set/enabled by adding stubs for 3 missing functions.

I've tried to follow Kconfig dependencies to see how could we have both
CONTIG_ALLOC=y and CONFIG_MEMORY_ISOLATION=n and I could not find how
was this possible.

We have

config CONTIG_ALLOC
def_bool (MEMORY_ISOLATION && COMPACTION) || CMA

and

config CMA
bool "Contiguous Memory Allocator"
depends on MMU
select MIGRATION
select MEMORY_ISOLATION

and alloc_contig_range() is hidden behind '#ifdef CONFIG_CONTIG_ALLOC'

In any rate, I think the better fix would be to update Kconfig
dependencies rather than add stubs for these functions.

> Fixes these build errors:
>
> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: mm/page_alloc.o: in function `alloc_contig_range':
> (.text+0xa0c0): undefined reference to `start_isolate_page_range'
> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa2bc): undefined reference to `test_pages_isolated'
> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa378): undefined reference to `undo_isolate_page_range'
>
> Fixes: 0815f3d81d76 ("mm: page_isolation: MIGRATE_CMA isolation functions added") # v3.10
> Fixes: b023f46813cd ("memory-hotplug: skip HWPoisoned page when offlining pages") # v3.10
> Reported-by: kernel test robot <[email protected]>
> Signed-off-by: Randy Dunlap <[email protected]>
> Cc: Michal Nazarewicz <[email protected]>
> Cc: Wen Congyang <[email protected]>
> Cc: Michal Simek <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Mike Rapoport <[email protected]>
> Cc: [email protected]
> ---
> include/linux/page-isolation.h | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> --- linux-next-20200903.orig/include/linux/page-isolation.h
> +++ linux-next-20200903/include/linux/page-isolation.h
> @@ -28,6 +28,22 @@ static inline bool is_migrate_isolate(in
> {
> return false;
> }
> +static inline int test_pages_isolated(unsigned long start_pfn,
> + unsigned long end_pfn, int isol_flags)
> +{
> + return 0;
> +}
> +static inline int
> +start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
> + unsigned migratetype, int flags)
> +{
> + return 0;
> +}
> +static inline void
> +undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
> + unsigned migratetype)
> +{
> +}
> #endif
>
> #define MEMORY_OFFLINE 0x1
>
>

--
Sincerely yours,
Mike.

2020-09-07 22:17:51

by Randy Dunlap

[permalink] [raw]
Subject: Re: [PATCH] <linux/page-isolation.h>: provide stubs for MEMORY_ISOLATION not set (for Microblaze)

On 9/7/20 12:05 AM, Mike Rapoport wrote:
> Hi Randy,
>
> On Sun, Sep 06, 2020 at 12:33:08PM -0700, Randy Dunlap wrote:
>> From: Randy Dunlap <[email protected]>
>>
>> Fix build errors in Microblaze when CONFIG_MEMORY_ISOLATION is not
>> set/enabled by adding stubs for 3 missing functions.
>
> I've tried to follow Kconfig dependencies to see how could we have both
> CONTIG_ALLOC=y and CONFIG_MEMORY_ISOLATION=n and I could not find how
> was this possible.
>
> We have
>
> config CONTIG_ALLOC
> def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
>
> and
>
> config CMA
> bool "Contiguous Memory Allocator"
> depends on MMU
> select MIGRATION
> select MEMORY_ISOLATION
>
> and alloc_contig_range() is hidden behind '#ifdef CONFIG_CONTIG_ALLOC'
>
> In any rate, I think the better fix would be to update Kconfig
> dependencies rather than add stubs for these functions.

OK, working on that. Should have something soon.


>> Fixes these build errors:
>>
>> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: mm/page_alloc.o: in function `alloc_contig_range':
>> (.text+0xa0c0): undefined reference to `start_isolate_page_range'
>> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa2bc): undefined reference to `test_pages_isolated'
>> gcc-9.3.0-nolibc/microblaze-linux/bin/microblaze-linux-ld: (.text+0xa378): undefined reference to `undo_isolate_page_range'
>>
>> Fixes: 0815f3d81d76 ("mm: page_isolation: MIGRATE_CMA isolation functions added") # v3.10
>> Fixes: b023f46813cd ("memory-hotplug: skip HWPoisoned page when offlining pages") # v3.10
>> Reported-by: kernel test robot <[email protected]>
>> Signed-off-by: Randy Dunlap <[email protected]>
>> Cc: Michal Nazarewicz <[email protected]>
>> Cc: Wen Congyang <[email protected]>
>> Cc: Michal Simek <[email protected]>
>> Cc: Christoph Hellwig <[email protected]>
>> Cc: Andrew Morton <[email protected]>
>> Cc: Mike Rapoport <[email protected]>
>> Cc: [email protected]
>> ---
>> include/linux/page-isolation.h | 16 ++++++++++++++++
>> 1 file changed, 16 insertions(+)


--
~Randy