From: Souptick Joarder <jrdr.linux@xxxxxxxxx> Subject: include/linux/hugetlb.h: convert to use vm_fault_t kbuild produces the below warning: tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 5453a3df2a5eb49bc24615d4cf0d66b2aae05e5f commit 3d3539018d2c ("mm: create the new vm_fault_t type") reproduce: # apt-get install sparse git checkout 3d3539018d2cbd12e5af4a132636ee7fd8d43ef0 make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' >> mm/memory.c:3968:21: sparse: incorrect type in assignment (different >> base types) @@ expected restricted vm_fault_t [usertype] ret @@ >> got e] ret @@ mm/memory.c:3968:21: expected restricted vm_fault_t [usertype] ret mm/memory.c:3968:21: got int This patch converts to return vm_fault_t type for hugetlb_fault() when CONFIG_HUGETLB_PAGE=n. Regarding the sparse warning, Luc said: : This is the expected behaviour. The constant 0 is magic regarding bitwise : types but ({ ...; 0; }) is not, it is just an ordinary expression of type : 'int'. : : So, IMHO, Souptick's patch is the right thing to do. Link: http://lkml.kernel.org/r/20190318162604.GA31553@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/hugetlb.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/include/linux/hugetlb.h~include-linux-hugetlbh-convert-to-use-vm_fault_t +++ a/include/linux/hugetlb.h @@ -203,7 +203,6 @@ static inline void hugetlb_show_meminfo( #define pud_huge(x) 0 #define is_hugepage_only_range(mm, addr, len) 0 #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; }) -#define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; }) #define hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma, dst_addr, \ src_addr, pagep) ({ BUG(); 0; }) #define huge_pte_offset(mm, address, sz) 0 @@ -234,6 +233,13 @@ static inline void __unmap_hugepage_rang { BUG(); } +static inline vm_fault_t hugetlb_fault(struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long address, + unsigned int flags) +{ + BUG(); + return 0; +} #endif /* !CONFIG_HUGETLB_PAGE */ /* _
