FROMLIST: mm: Call arch_swap_restore() from do_swap_page()

Commit c145e0b47c ("mm: streamline COW logic in do_swap_page()") moved
the call to swap_free() before the call to set_pte_at(), which meant that
the MTE tags could end up being freed before set_pte_at() had a chance
to restore them. Fix it by adding a call to the arch_swap_restore() hook
before the call to swap_free().

Signed-off-by: Peter Collingbourne <pcc@google.com>
Link: https://linux-review.googlesource.com/id/I6470efa669e8bd2f841049b8c61020c510678965
Cc: <stable@vger.kernel.org> # 6.1
Fixes: c145e0b47c ("mm: streamline COW logic in do_swap_page()")
Reported-by: Qun-wei Lin (林群崴) <Qun-wei.Lin@mediatek.com>
Closes: https://lore.kernel.org/all/5050805753ac469e8d727c797c2218a9d780d434.camel@mediatek.com/
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/all/20230523004312.1807357-2-pcc@google.com/
Change-Id: I6470efa669e8bd2f841049b8c61020c510678965
Bug: 274890466
This commit is contained in:
Peter Collingbourne 2023-05-12 11:19:49 -07:00
parent 098028adf7
commit 3805b879f5

View File

@ -3970,6 +3970,13 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
}
}
/*
* Some architectures may have to restore extra metadata to the page
* when reading from swap. This metadata may be indexed by swap entry
* so this must be called before swap_free().
*/
arch_swap_restore(entry, folio);
/*
* Remove the swap entry and conditionally try to free up the swapcache.
* We're already holding a reference on the page but haven't mapped it