This is a note to let you know that I've just added the patch titled
x86/vm86: Fix unused variable warning if THP is disabled
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-vm86-fix-unused-variable-warning-if-thp-is-disabled.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3ba5b5ea7dc3a10ef50819b43a9f8de2705f4eec Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Date: Mon, 13 Feb 2017 15:52:28 +0300
Subject: x86/vm86: Fix unused variable warning if THP is disabled
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From: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
commit 3ba5b5ea7dc3a10ef50819b43a9f8de2705f4eec upstream.
GCC complains about unused variable 'vma' in mark_screen_rdonly() if THP is
disabled:
arch/x86/kernel/vm86_32.c: In function ‘mark_screen_rdonly’:
arch/x86/kernel/vm86_32.c:180:26: warning: unused variable ‘vma’
[-Wunused-variable]
struct vm_area_struct *vma = find_vma(mm, 0xA0000);
That's silly. pmd_trans_huge() resolves to 0 when THP is disabled, so the
whole block should be eliminated.
Moving the variable declaration outside the if() block shuts GCC up.
Reported-by: Jérémy Lefaure <jeremy.lefaure@xxxxxxxxxxxx>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Tested-by: Borislav Petkov <bp@xxxxxxx>
Cc: Carlos O'Donell <carlos@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170213125228.63645-1-kirill.shutemov@xxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/vm86_32.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -160,11 +160,12 @@ void save_v86_state(struct kernel_vm86_r
static void mark_screen_rdonly(struct mm_struct *mm)
{
+ struct vm_area_struct *vma;
+ spinlock_t *ptl;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
- spinlock_t *ptl;
int i;
down_write(&mm->mmap_sem);
@@ -177,7 +178,7 @@ static void mark_screen_rdonly(struct mm
pmd = pmd_offset(pud, 0xA0000);
if (pmd_trans_huge(*pmd)) {
- struct vm_area_struct *vma = find_vma(mm, 0xA0000);
+ vma = find_vma(mm, 0xA0000);
split_huge_pmd(vma, pmd, 0xA0000);
}
if (pmd_none_or_clear_bad(pmd))
Patches currently in stable-queue which might be from kirill.shutemov@xxxxxxxxxxxxxxx are
queue-4.9/x86-vm86-fix-unused-variable-warning-if-thp-is-disabled.patch
queue-4.9/shmem-avoid-maybe-uninitialized-warning.patch