search for: page_ref_freez

...speculative pagecache lookup that runs just before __remove_mapping, can cause __remove_mapping to fail despite try_to_free_buffers() succeeded before it (like if there was a transient or long term GUP pin). speculative lookup that can happen across all page struct at all times and they will cause page_ref_freeze in __remove_mapping to fail. I'm sure I'm missing details on the ext4 __writepage problem and how set_page_dirty_lock broke stuff with long term GUP pins, so I'm asking... Thanks! Andrea

On Thu, Mar 07, 2019 at 10:45:57AM +0800, Jason Wang wrote: > > On 2019/3/7 ??12:31, Michael S. Tsirkin wrote: > > > +static void vhost_set_vmap_dirty(struct vhost_vmap *used) > > > +{ > > > + int i; > > > + > > > + for (i = 0; i < used->npages; i++) > > > + set_page_dirty_lock(used->pages[i]); > > This seems to rely on

On Thu, Mar 07, 2019 at 10:45:57AM +0800, Jason Wang wrote: > > On 2019/3/7 ??12:31, Michael S. Tsirkin wrote: > > > +static void vhost_set_vmap_dirty(struct vhost_vmap *used) > > > +{ > > > + int i; > > > + > > > + for (i = 0; i < used->npages; i++) > > > + set_page_dirty_lock(used->pages[i]); > > This seems to rely on

On Thu, Mar 07, 2019 at 10:34:39AM -0500, Michael S. Tsirkin wrote: > On Thu, Mar 07, 2019 at 10:45:57AM +0800, Jason Wang wrote: > > > > On 2019/3/7 ??12:31, Michael S. Tsirkin wrote: > > > > +static void vhost_set_vmap_dirty(struct vhost_vmap *used) > > > > +{ > > > > + int i; > > > > + > > > > + for (i = 0; i <

...R if protections changed and TLB flush necessary */ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, pgprot_t newprot, unsigned long cp_flags) @@ -2689,7 +2701,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) if (!mapcount && page_ref_freeze(head, 1 + extra_pins)) { if (!list_empty(page_deferred_list(head))) { ds_queue->split_queue_len--; - list_del(page_deferred_list(head)); + list_del_init(page_deferred_list(head)); } spin_unlock(&ds_queue->split_queue_lock); if (mapping) { @@ -2743,7 +2755,7 @@ void fr...

...he lookup that runs just before __remove_mapping, can cause > __remove_mapping to fail despite try_to_free_buffers() succeeded > before it (like if there was a transient or long term GUP > pin). speculative lookup that can happen across all page struct at all > times and they will cause page_ref_freeze in __remove_mapping to > fail. > > I'm sure I'm missing details on the ext4 __writepage problem and how > set_page_dirty_lock broke stuff with long term GUP pins, so I'm > asking... O_DIRECT can suffer from the same issue but the race window for that is small enough th...

...he lookup that runs just before __remove_mapping, can cause > __remove_mapping to fail despite try_to_free_buffers() succeeded > before it (like if there was a transient or long term GUP > pin). speculative lookup that can happen across all page struct at all > times and they will cause page_ref_freeze in __remove_mapping to > fail. > > I'm sure I'm missing details on the ext4 __writepage problem and how > set_page_dirty_lock broke stuff with long term GUP pins, so I'm > asking... O_DIRECT can suffer from the same issue but the race window for that is small enough th...

...and TLB flush necessary > */ > int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, > unsigned long addr, pgprot_t newprot, unsigned long cp_flags) > @@ -2689,7 +2701,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) > if (!mapcount && page_ref_freeze(head, 1 + extra_pins)) { > if (!list_empty(page_deferred_list(head))) { > ds_queue->split_queue_len--; > - list_del(page_deferred_list(head)); > + list_del_init(page_deferred_list(head)); > } > spin_unlock(&ds_queue->split_queue_lock); > if (mappi...

...} - unmap_page(head); + if (remap) + unmap_page(head); VM_BUG_ON_PAGE(compound_mapcount(head), head); /* prevent PageLRU to go away from under us, and freeze lru stats */ @@ -2717,7 +2756,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) if (!mapcount && page_ref_freeze(head, 1 + extra_pins)) { if (!list_empty(page_deferred_list(head))) { ds_queue->split_queue_len--; - list_del(page_deferred_list(head)); + list_del_init(page_deferred_list(head)); } spin_unlock(&ds_queue->split_queue_lock); if (mapping) { @@ -2727,7 +2766,7 @@ int spl...

These patches apply to linux-5.8.0-rc1. Patches 1-3 should probably go into 5.8, the others can be queued for 5.9. Patches 4-6 improve the HMM self tests. Patch 7-8 prepare nouveau for the meat of this series which adds support and testing for compound page mapping of system memory (patches 9-11) and compound page migration to device private memory (patches 12-16). Since these changes are split

This series adds support for transparent huge page migration to migrate_vma_*() and adds nouveau SVM and HMM selftests as consumers. Earlier versions were posted previously [1] and [2]. The patches apply cleanly to the linux-mm 5.10.0-rc2 tree. There are a lot of other THP patches being posted. I don't think there are any semantic conflicts but there may be some merge conflicts depending on

This series adds support for transparent huge page migration to migrate_vma_*() and adds nouveau SVM and HMM selftests as consumers. An earlier version was posted previously [1]. This version now supports splitting a THP midway in the migration process which led to a number of changes. The patches apply cleanly to the current linux-mm tree. Since there are a couple of patches in linux-mm from Dan