On 22.11.22 07:53, Stephen Rothwell wrote:
Hi all,
After merging the mm tree, today's linux-next build (x86_64 allmodconfig)
failed like this:
In file included from include/uapi/linux/posix_types.h:5,
from include/uapi/linux/types.h:14,
from include/linux/types.h:6,
from include/linux/kasan-checks.h:5,
from include/asm-generic/rwonce.h:26,
from ./arch/powerpc/include/generated/asm/rwonce.h:1,
from include/linux/compiler.h:247,
from include/linux/build_bug.h:5,
from include/linux/container_of.h:5,
from include/linux/list.h:5,
from mm/hugetlb.c:6:
mm/hugetlb.c: In function 'add_hugetlb_page':
include/linux/stddef.h:8:14: warning: passing argument 2 of 'set_page_private' makes integer from pointer without a cast [-Wint-conversion]
8 | #define NULL ((void *)0)
| ^~~~~~~~~~~
| |
| void *
mm/hugetlb.c:1533:32: note: in expansion of macro 'NULL'
1533 | set_page_private(page, NULL);
| ^~~~
In file included from include/linux/mmzone.h:21,
from include/linux/gfp.h:7,
from include/linux/mm.h:7,
from mm/hugetlb.c:8:
include/linux/mm_types.h:464:70: note: expected 'long unsigned int' but argument is of type 'void *'
464 | static inline void set_page_private(struct page *page, unsigned long private)
| ~~~~~~~~~~~~~~^~~~~~~
Caused by commit
1f0d844bcc5b ("mm/hugetlb: stop using 0 as NULL pointer")
set_page_private() have taken an unsigned long as its second argument
since (at least) v5.8-rc1. The cited bugzilla refers to next-20221121,
but even there:
$ git grep set_page_private next-20221121:include/linux/mm_types.h
next-20221121:include/linux/mm_types.h:static inline void set_page_private(struct page *page, unsigned long private)
In fact the bugzilla refers to mm/hugetlb.c line 1531. In next-20221121
that is:
folio_change_private(folio, 0);
I have reverted that commit for today. Please take more care :-(
Heh, that warning complains about the call to folio_change_private():
$ git show e4cd8d3ff7f9efeb97330e5e9b99eeb2a68f5cf9:mm/hugetlb.c | sed -n '1531p'
folio_change_private(folio, 0);
And that one is indeed:
$ git grep folio_change_private e4cd8d3ff7f9efeb97330e5e9b99eeb2a68f5cf9:include/linux/pagemap.h
e4cd8d3ff7f9efeb97330e5e9b99eeb2a68f5cf9:include/linux/pagemap.h: * folio_change_private - Change private data on a folio.
e4cd8d3ff7f9efeb97330e5e9b99eeb2a68f5cf9:include/linux/pagemap.h:static inline void *folio_change_private(struct folio *folio, void *data)
I missed in my review that the patch changes set_page_private()
instead because it was applied to the wrong tree ...
The folio_change_private() change is/was from Sidhartha Kumar:
commit 032158fde0b2a59cda2c66a8773135af2a04535e
Author: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
Date: Thu Nov 17 13:14:57 2022 -0800
mm/hugetlb: convert add_hugetlb_page() to folios and add hugetlb_cma_folio()
Convert add_hugetlb_page() to take in a folio, also convert
hugetlb_cma_page() to take in a folio.
Link: https://lkml.kernel.org/r/20221117211501.17150-7-sidhartha.kumar@xxxxxxxxxx
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
--
Thanks,
David / dhildenb
