| Message ID | 20190912213110.3691-1-richardw.yang@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] fs/userfaultfd.c: remove a redundant check on end | expand |
Ping for comment :-) On Fri, Sep 13, 2019 at 05:31:08AM +0800, Wei Yang wrote: >For the ending vma, there is a check to make sure the end is huge page >aligned. > >The *if* check makes sure vm_start < end <= vm_end. While the first half >is not necessary, because the *for* clause makes sure vm_start < end. > >This patch just removes it. > >Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> >--- > fs/userfaultfd.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > >diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c >index 653d8f7c453c..9ce09ac619a2 100644 >--- a/fs/userfaultfd.c >+++ b/fs/userfaultfd.c >@@ -1402,8 +1402,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, > * If this vma contains ending address, and huge pages > * check alignment. > */ >- if (is_vm_hugetlb_page(cur) && end <= cur->vm_end && >- end > cur->vm_start) { >+ if (is_vm_hugetlb_page(cur) && end <= cur->vm_end) { > unsigned long vma_hpagesize = vma_kernel_pagesize(cur); > > ret = -EINVAL; >-- >2.17.1
On Fri, Sep 13, 2019 at 05:31:08AM +0800, Wei Yang wrote: >For the ending vma, there is a check to make sure the end is huge page >aligned. > >The *if* check makes sure vm_start < end <= vm_end. While the first half >is not necessary, because the *for* clause makes sure vm_start < end. > >This patch just removes it. > Does this one look good? >Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> >--- > fs/userfaultfd.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > >diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c >index 653d8f7c453c..9ce09ac619a2 100644 >--- a/fs/userfaultfd.c >+++ b/fs/userfaultfd.c >@@ -1402,8 +1402,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, > * If this vma contains ending address, and huge pages > * check alignment. > */ >- if (is_vm_hugetlb_page(cur) && end <= cur->vm_end && >- end > cur->vm_start) { >+ if (is_vm_hugetlb_page(cur) && end <= cur->vm_end) { > unsigned long vma_hpagesize = vma_kernel_pagesize(cur); > > ret = -EINVAL; >-- >2.17.1
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 653d8f7c453c..9ce09ac619a2 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1402,8 +1402,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, * If this vma contains ending address, and huge pages * check alignment. */ - if (is_vm_hugetlb_page(cur) && end <= cur->vm_end && - end > cur->vm_start) { + if (is_vm_hugetlb_page(cur) && end <= cur->vm_end) { unsigned long vma_hpagesize = vma_kernel_pagesize(cur); ret = -EINVAL;
For the ending vma, there is a check to make sure the end is huge page aligned. The *if* check makes sure vm_start < end <= vm_end. While the first half is not necessary, because the *for* clause makes sure vm_start < end. This patch just removes it. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> --- fs/userfaultfd.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)