Messages in this thread | | | From | Dan Williams <> | Date | Sun, 17 Jan 2021 14:35:36 -0800 | Subject | Re: [PATCH v4 4/5] mm: Fix page reference leak in soft_offline_page() |
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On Sun, Jan 17, 2021 at 2:01 PM Andrew Morton <akpm@linux-foundation.org> wrote: > > On Wed, 13 Jan 2021 16:43:32 -0800 Dan Williams <dan.j.williams@intel.com> wrote: > > > The conversion to move pfn_to_online_page() internal to > > soft_offline_page() missed that the get_user_pages() reference taken by > > the madvise() path needs to be dropped when pfn_to_online_page() fails. > > Note the direct sysfs-path to soft_offline_page() does not perform a > > get_user_pages() lookup. > > > > When soft_offline_page() is handed a pfn_valid() && > > !pfn_to_online_page() pfn the kernel hangs at dax-device shutdown due to > > a leaked reference. > > > > Fixes: feec24a6139d ("mm, soft-offline: convert parameter to pfn") > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> > > Cc: Michal Hocko <mhocko@kernel.org> > > Reviewed-by: David Hildenbrand <david@redhat.com> > > Reviewed-by: Oscar Salvador <osalvador@suse.de> > > Cc: <stable@vger.kernel.org> > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > > A cc:stable patch in the middle is awkward. I'll make this a > standalone patch for merging into mainline soon (for 5.11) and shall > turn the rest into a 4-patch series, OK?
Sounds good to me.
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