[ Upstream commit 94393c78964c432917014e3a456fa15c3e78f741 ]
Since 0cbe3e26abe0 ("mm: update ptep_modify_prot_start/commit to take vm_area_struct as arg") the only place that uses the local 'mm' variable in change_pte_range() is the call to set_pte_at().
Many architectures define set_pte_at() as macro that does not use the 'mm' parameter, which generates the following compilation warning:
CC mm/mprotect.o mm/mprotect.c: In function 'change_pte_range': mm/mprotect.c:42:20: warning: unused variable 'mm' [-Wunused-variable] struct mm_struct *mm = vma->vm_mm; ^~
Fix it by passing vma->mm to set_pte_at() and dropping the local 'mm' variable in change_pte_range().
[liu.song.a23@gmail.com: fix missed conversions] Link: http://lkml.kernel.org/r/CAPhsuW6wcQgYLHNdBdw6m0YiR4RWsS4XzfpSKU7wBLLeOCTbpw...: http://lkml.kernel.org/r/1557305432-4940-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport rppt@linux.ibm.com Reviewed-by: Andrew Morton akpm@linux-foundation.org Cc: Song Liu liu.song.a23@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- mm/mprotect.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/mm/mprotect.c b/mm/mprotect.c index 028c724dcb1a..ab40f3d04aa3 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -39,7 +39,6 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t newprot, int dirty_accountable, int prot_numa) { - struct mm_struct *mm = vma->vm_mm; pte_t *pte, oldpte; spinlock_t *ptl; unsigned long pages = 0; @@ -136,7 +135,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, newpte = swp_entry_to_pte(entry); if (pte_swp_soft_dirty(oldpte)) newpte = pte_swp_mksoft_dirty(newpte); - set_pte_at(mm, addr, pte, newpte); + set_pte_at(vma->vm_mm, addr, pte, newpte);
pages++; } @@ -150,7 +149,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, */ make_device_private_entry_read(&entry); newpte = swp_entry_to_pte(entry); - set_pte_at(mm, addr, pte, newpte); + set_pte_at(vma->vm_mm, addr, pte, newpte);
pages++; }