Re: [PATCH v5 5/5] mm: selftests: Add shmem into memory failure test

[Ackerley Tng]

Lisa Wang <wyihan@xxxxxxxxxx> writes:

> On Mon, Aug 24, 2026 at 03:00:47PM +0200, David Hildenbrand (Arm) wrote:
>> > +++ b/tools/testing/selftests/mm/memory-failure.c
>> > @@ -20,6 +20,10 @@
>> >
>> >  #include "vm_util.h"
>> >
>> > +#ifndef fallthrough
>> > +# define fallthrough __attribute__((__fallthrough__))
>> > +#endif
>>
>> This doesn't belong into this test.
>>
>> rseq/rseq.c selftest already uses it.
>>
>> I think tools/testing/include/ already provides it.
>>
>> Maybe
>>
>> 	#include <linux/compiler.h>
>>
>> does the trick?
>
> Hi David,
> Thank you for replying.
> Would it be better to change it to /* FALLTHROUGH */
> like the rest of the mm selftests?
>
> If we prefer to include <linux/compiler.h>, we can
> certainly do that, but we would also need to update
> the Makefile and fix a redefinition in pkey-helpers.h.
>
> --- a/tools/testing/selftests/mm/Makefile
> +++ b/tools/testing/selftests/mm/Makefile
> @@ -37,7 +37,7 @@ endif
>  # LDLIBS.
>  MAKEFLAGS += --no-builtin-rules
>
> -CFLAGS = -Wall -O2 -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES) $(TOOLS_INCLUDES)
> +CFLAGS = -Wall -O2 -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES) $(TOOLS_INCLUDES) -I$(top_srcdir)/tools/include
>  CFLAGS += -Wunreachable-code
>  LDLIBS = -lrt -lpthread -lm
>
> --- a/tools/testing/selftests/mm/pkey-helpers.h
> +++ b/tools/testing/selftests/mm/pkey-helpers.h
> @@ -22,7 +22,7 @@
>  typedef __u8   u8;
>  typedef __u16  u16;
>  typedef __u32  u32;
> -typedef __u64  u64;
> +// typedef __u64       u64;

Removing this u64 typedef seems to be unrelated, the layers of includes
probably has some weirdness that needs to be ironed out.

If the weirdness is not too complex to iron out to be in time for 7.4, I
think we can iron that out, if not perhaps using /* FALLTHROUGH */ is
fine, to be aligned with the other mm selftests.

>
>
> Lisa