| Message ID | 20220814140534.363348-2-haiyue.wang@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | fix follow_page related issues | expand |
On 14.08.22 16:05, Haiyue Wang wrote: > The commit > 3218f8712d6b ("mm: handling Non-LRU pages returned by vm_normal_pages") > doesn't handle the follow_page with flag FOLL_GET correctly, this will > do get_page on page, it shouldn't just return directly without put_page. > > So revert the related fix to prepare for clean patch to handle Non-LRU > pages returned by follow_page. What? Why? Just fix it.
> -----Original Message----- > From: David Hildenbrand <david@redhat.com> > Sent: Monday, August 15, 2022 00:31 > To: Wang, Haiyue <haiyue.wang@intel.com>; linux-mm@kvack.org; linux-kernel@vger.kernel.org > Cc: akpm@linux-foundation.org; linmiaohe@huawei.com; Huang, Ying <ying.huang@intel.com>; > songmuchun@bytedance.com; naoya.horiguchi@linux.dev; alex.sierra@amd.com > Subject: Re: [PATCH v2 1/3] mm: revert handling Non-LRU pages returned by follow_page > > On 14.08.22 16:05, Haiyue Wang wrote: > > The commit > > 3218f8712d6b ("mm: handling Non-LRU pages returned by vm_normal_pages") > > doesn't handle the follow_page with flag FOLL_GET correctly, this will > > do get_page on page, it shouldn't just return directly without put_page. > > > > So revert the related fix to prepare for clean patch to handle Non-LRU > > pages returned by follow_page. > > What? Why? > Just as the cover letter said, for applying the PATCH 2/3 can be applied on Linux-5.19 branch directly. I will drop this kind of fix, and fix the issue directly in v3. > Just fix it. > > -- > Thanks, > > David / dhildenb
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8a7c1b344abe..2ee6d38a1426 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2963,7 +2963,7 @@ static int split_huge_pages_pid(int pid, unsigned long vaddr_start, /* FOLL_DUMP to ignore special (like zero) pages */ page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP); - if (IS_ERR_OR_NULL(page) || is_zone_device_page(page)) + if (IS_ERR_OR_NULL(page)) continue; if (!is_transparent_hugepage(page)) diff --git a/mm/ksm.c b/mm/ksm.c index 42ab153335a2..fe3e0a39f73a 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -475,7 +475,7 @@ static int break_ksm(struct vm_area_struct *vma, unsigned long addr) cond_resched(); page = follow_page(vma, addr, FOLL_GET | FOLL_MIGRATION | FOLL_REMOTE); - if (IS_ERR_OR_NULL(page) || is_zone_device_page(page)) + if (IS_ERR_OR_NULL(page)) break; if (PageKsm(page)) ret = handle_mm_fault(vma, addr, @@ -560,7 +560,7 @@ static struct page *get_mergeable_page(struct rmap_item *rmap_item) goto out; page = follow_page(vma, addr, FOLL_GET); - if (IS_ERR_OR_NULL(page) || is_zone_device_page(page)) + if (IS_ERR_OR_NULL(page)) goto out; if (PageAnon(page)) { flush_anon_page(vma, page, addr); @@ -2308,7 +2308,7 @@ static struct rmap_item *scan_get_next_rmap_item(struct page **page) if (ksm_test_exit(mm)) break; *page = follow_page(vma, ksm_scan.address, FOLL_GET); - if (IS_ERR_OR_NULL(*page) || is_zone_device_page(*page)) { + if (IS_ERR_OR_NULL(*page)) { ksm_scan.address += PAGE_SIZE; cond_resched(); continue; diff --git a/mm/migrate.c b/mm/migrate.c index 6a1597c92261..3d5f0262ab60 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1672,7 +1672,7 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, goto out; err = -ENOENT; - if (!page || is_zone_device_page(page)) + if (!page) goto out; err = 0; @@ -1863,7 +1863,7 @@ static void do_pages_stat_array(struct mm_struct *mm, unsigned long nr_pages, if (IS_ERR(page)) goto set_status; - if (page && !is_zone_device_page(page)) { + if (page) { err = page_to_nid(page); put_page(page); } else {
The commit 3218f8712d6b ("mm: handling Non-LRU pages returned by vm_normal_pages") doesn't handle the follow_page with flag FOLL_GET correctly, this will do get_page on page, it shouldn't just return directly without put_page. So revert the related fix to prepare for clean patch to handle Non-LRU pages returned by follow_page. Signed-off-by: Haiyue Wang <haiyue.wang@intel.com> --- mm/huge_memory.c | 2 +- mm/ksm.c | 6 +++--- mm/migrate.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-)