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[172.10.233.147]) by smtp.gmail.com with ESMTPSA id f84sm116368oia.32.2020.08.22.19.16.52 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Sat, 22 Aug 2020 19:16:55 -0700 (PDT) Date: Sat, 22 Aug 2020 19:16:39 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Sasha Levin cc: Hugh Dickins , Greg KH , aarcange@redhat.com, akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, mike.kravetz@oracle.com, songliubraving@fb.com, torvalds@linux-foundation.org, stable-commits@vger.kernel.org, stable@vger.kernel.org Subject: Re: Patch "khugepaged: khugepaged_test_exit() check mmget_still_valid()" has been added to the 5.8-stable tree In-Reply-To: <20200822212053.GE8670@sasha-vm> Message-ID: References: <1597841669128213@kroah.com> <20200819135306.GA3311904@kroah.com> <20200822212053.GE8670@sasha-vm> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Sat, 22 Aug 2020, Sasha Levin wrote: > > I've followed your instructions and backported the patches: > > bbe98f9cadff ("khugepaged: khugepaged_test_exit() check > mmget_still_valid()") - to all branches. > f3f99d63a815 ("khugepaged: adjust VM_BUG_ON_MM() in > __khugepaged_enter()") - to all branches. > 59ea6d06cfa9 ("coredump: fix race condition between collapse_huge_page() > and core dumping") - for 4.4. That's saved me time, thanks a lot for doing that work, Sasha. I've checked the results (haha, read on) and they're all fine, but one minor flaw in bisectability: the added 4.4 backport of "coredump: fix race condition..." adds a line (deleted by the next commit) result = SCAN_ANY_PROCESS; but neither "result" nor "SCAN_ANY_PROCESS" is defined in that tree, so that intermediate step would generate an easily fixed build error. FWIW - I don't know whether that's something to care about or not. Thanks again, Hugh