On 09/22, Peter Xu wrote: > > On Tue, Sep 22, 2020 at 05:48:46PM +0200, Oleg Nesterov wrote: > > > However since I didn't change this logic in this patch, it probably means this > > > bug is also in the original code before this series... I'm thinking maybe I > > > should prepare a standalone patch to clear the swp_entry_t and cc stable. > > > > Well, if copy_one_pte(src_pte) hits a swap entry and returns entry.val != 0, then > > pte_none(*src_pte) is not possible after restart? This means that copy_one_pte() > > will be called at least once. > > Note that we've released the page table locks, so afaict the old swp entry can > be gone under us when we go back to the "do" loop... :) But how? I am just curious, I don't understand this code enough. Oleg.
