| Message ID | 153154380137.34503.3754023882460956800.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Jerome, Is it possible to get an ack for this? Thanks! On 07/13/2018 09:50 PM, Dan Williams wrote: > MEMORY_DEVICE_FS_DAX relies on typical page semantics whereby ->mapping > is only ever cleared by truncation, not final put. > > Without this fix dax pages may forget their mapping association at the > end of every page pin event. > > Move this atypical behavior that HMM wants into the HMM ->page_free() > callback. > > Cc: <stable@vger.kernel.org> > Cc: Jan Kara <jack@suse.cz> > Cc: Jérôme Glisse <jglisse@redhat.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Ross Zwisler <ross.zwisler@linux.intel.com> > Fixes: d2c997c0f145 ("fs, dax: use page->mapping...") > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > --- > kernel/memremap.c | 1 - > mm/hmm.c | 2 ++ > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/memremap.c b/kernel/memremap.c > index 5857267a4af5..62603634a1d2 100644 > --- a/kernel/memremap.c > +++ b/kernel/memremap.c > @@ -339,7 +339,6 @@ void __put_devmap_managed_page(struct page *page) > __ClearPageActive(page); > __ClearPageWaiters(page); > > - page->mapping = NULL; > mem_cgroup_uncharge(page); > > page->pgmap->page_free(page, page->pgmap->data); > diff --git a/mm/hmm.c b/mm/hmm.c > index de7b6bf77201..f9d1d89dec4d 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -963,6 +963,8 @@ static void hmm_devmem_free(struct page *page, void *data) > { > struct hmm_devmem *devmem = data; > > + page->mapping = NULL; > + > devmem->ops->free(devmem, page); > } > > > _______________________________________________ > Linux-nvdimm mailing list > Linux-nvdimm@lists.01.org > https://lists.01.org/mailman/listinfo/linux-nvdimm >
On Mon, Jul 23, 2018 at 09:12:06AM -0700, Dave Jiang wrote: > Jerome, > Is it possible to get an ack for this? Thanks! > > On 07/13/2018 09:50 PM, Dan Williams wrote: > > MEMORY_DEVICE_FS_DAX relies on typical page semantics whereby ->mapping > > is only ever cleared by truncation, not final put. > > > > Without this fix dax pages may forget their mapping association at the > > end of every page pin event. > > > > Move this atypical behavior that HMM wants into the HMM ->page_free() > > callback. > > > > Cc: <stable@vger.kernel.org> > > Cc: Jan Kara <jack@suse.cz> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Ross Zwisler <ross.zwisler@linux.intel.com> > > Fixes: d2c997c0f145 ("fs, dax: use page->mapping...") > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Jérôme Glisse <jglisse@redhat.com> > > --- > > kernel/memremap.c | 1 - > > mm/hmm.c | 2 ++ > > 2 files changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/memremap.c b/kernel/memremap.c > > index 5857267a4af5..62603634a1d2 100644 > > --- a/kernel/memremap.c > > +++ b/kernel/memremap.c > > @@ -339,7 +339,6 @@ void __put_devmap_managed_page(struct page *page) > > __ClearPageActive(page); > > __ClearPageWaiters(page); > > > > - page->mapping = NULL; > > mem_cgroup_uncharge(page); > > > > page->pgmap->page_free(page, page->pgmap->data); > > diff --git a/mm/hmm.c b/mm/hmm.c > > index de7b6bf77201..f9d1d89dec4d 100644 > > --- a/mm/hmm.c > > +++ b/mm/hmm.c > > @@ -963,6 +963,8 @@ static void hmm_devmem_free(struct page *page, void *data) > > { > > struct hmm_devmem *devmem = data; > > > > + page->mapping = NULL; > > + > > devmem->ops->free(devmem, page); > > } > > > > > > _______________________________________________ > > Linux-nvdimm mailing list > > Linux-nvdimm@lists.01.org > > https://lists.01.org/mailman/listinfo/linux-nvdimm > >
diff --git a/kernel/memremap.c b/kernel/memremap.c index 5857267a4af5..62603634a1d2 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -339,7 +339,6 @@ void __put_devmap_managed_page(struct page *page) __ClearPageActive(page); __ClearPageWaiters(page); - page->mapping = NULL; mem_cgroup_uncharge(page); page->pgmap->page_free(page, page->pgmap->data); diff --git a/mm/hmm.c b/mm/hmm.c index de7b6bf77201..f9d1d89dec4d 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -963,6 +963,8 @@ static void hmm_devmem_free(struct page *page, void *data) { struct hmm_devmem *devmem = data; + page->mapping = NULL; + devmem->ops->free(devmem, page); }
MEMORY_DEVICE_FS_DAX relies on typical page semantics whereby ->mapping is only ever cleared by truncation, not final put. Without this fix dax pages may forget their mapping association at the end of every page pin event. Move this atypical behavior that HMM wants into the HMM ->page_free() callback. Cc: <stable@vger.kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Fixes: d2c997c0f145 ("fs, dax: use page->mapping...") Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- kernel/memremap.c | 1 - mm/hmm.c | 2 ++ 2 files changed, 2 insertions(+), 1 deletion(-)