Messages in this thread |  | | Date | Sun, 24 Apr 2022 15:45:02 +0800 | From | Muchun Song <> | Subject | Re: [PATCH] mm: hugetlb: Add missing cache flushing in hugetlb_unshare_all_pmds() |
| |
On Sun, Apr 24, 2022 at 02:33:19PM +0800, Baolin Wang wrote: > Missed calling flush_cache_range() before removing the sharing PMD entrires, > otherwise data consistence issue may be occurred on some architectures whose > caches are strict and require a virtual–>physical translation to exist for > a virtual address. Thus add it. > > Fixes: 6dfeaff93be1 ("hugetlb/userfaultfd: unshare all pmds for hugetlbfs when register wp") > Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
CONFIG_ARCH_WANT_HUGE_PMD_SHARE is only definded on riscv, arm64 and x86. All of them do not have a VIVT cache. In others words, flush_cache_range() is null on those architectures. So I suspect in practice this does not cause any issue. It is better to clarify this in commit log.
Anyway:
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Thanks.
|  |