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| author | Thomas Zimmermann <[email protected]> | 2024-03-13 08:43:21 +0000 |
|---|---|---|
| committer | Thomas Zimmermann <[email protected]> | 2024-03-13 08:43:21 +0000 |
| commit | a2e7496b453eaa577425858d6f8b854800ed7343 (patch) | |
| tree | 35d05023d51161a28768a29115c8e03e65599fe5 /mm/memory.c | |
| parent | nouveau/dmem: handle kcalloc() allocation failure (diff) | |
| parent | nouveau: lock the client object tree. (diff) | |
| download | kernel-a2e7496b453eaa577425858d6f8b854800ed7343.tar.gz kernel-a2e7496b453eaa577425858d6f8b854800ed7343.zip | |
Merge drm/drm-fixes into drm-misc-fixes
Backmerging to sync before merging the patchset at [1].
[1] https://lore.kernel.org/all/[email protected]/
Signed-off-by: Thomas Zimmermann <[email protected]>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/mm/memory.c b/mm/memory.c index 15f8b10ea17c..0bfc8b007c01 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3799,6 +3799,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) struct page *page; struct swap_info_struct *si = NULL; rmap_t rmap_flags = RMAP_NONE; + bool need_clear_cache = false; bool exclusive = false; swp_entry_t entry; pte_t pte; @@ -3867,6 +3868,20 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) if (!folio) { if (data_race(si->flags & SWP_SYNCHRONOUS_IO) && __swap_count(entry) == 1) { + /* + * Prevent parallel swapin from proceeding with + * the cache flag. Otherwise, another thread may + * finish swapin first, free the entry, and swapout + * reusing the same entry. It's undetectable as + * pte_same() returns true due to entry reuse. + */ + if (swapcache_prepare(entry)) { + /* Relax a bit to prevent rapid repeated page faults */ + schedule_timeout_uninterruptible(1); + goto out; + } + need_clear_cache = true; + /* skip swapcache */ folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, vma, vmf->address, false); @@ -4117,6 +4132,9 @@ unlock: if (vmf->pte) pte_unmap_unlock(vmf->pte, vmf->ptl); out: + /* Clear the swap cache pin for direct swapin after PTL unlock */ + if (need_clear_cache) + swapcache_clear(si, entry); if (si) put_swap_device(si); return ret; @@ -4131,6 +4149,8 @@ out_release: folio_unlock(swapcache); folio_put(swapcache); } + if (need_clear_cache) + swapcache_clear(si, entry); if (si) put_swap_device(si); return ret; |