From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793672136; b=mcovWpfznWq3WMxQ8yT5RsOVPRXIjBmSUv74l50ZtZsrCxCHxorLoEcHImPZF14bpWt7 5KbvUalL61jt/uuYrWM+PGvBl0l82ChwNDRZU0FJs7yagMhJLXseSioZKBAiJgtvkj9F+ 84njcCoSHcXdCRfgZnaIkDNHm98U91Esf+xyK0zlKs9z2WlYAe4WhNanmWRYTwWcBrdjs QDDI4rLvsEU1FcEuKQsezuOy9bM8gIAFmtubmYWhc5fu3RVS4RUYlEUEbzc++FFHmgiWl ZF2Cn97xYLjjN2ZJoxDTtd2p3LKMMfRrUIc59fMylTLuRTkIbCFjmgQ7g2nTz0VtNnQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793672136; h=Received:DKIM-Signature:Date:To:From:Subject:Message-Id; bh=81c/CIbeUI49AQeq8U0mWkFHFiq032kJ91gY7TvTAKQ=; b=pmDU+6L/TAU53FGGUmvaVUVgIx6am2B2hD6CVl5yS7jMnzTYnu+ufUToF0HyayJpXhVb 9WURhB04BUKdmRKJ58OQGcegCrOBqx8UMnpJzyRp75wq0dWYMPwKXdQqF1Ork+Fpbf419 RSsIHjyk9O0wm0Ss2OqAIqMR1xFm6dc33x+N4yONHWnXhdVqXF2AIJW6qkls+uGlL2ja1 NtdgpFHzlnjDR2l5e1V4TanO7X/ACxWwj2DwbUHgPXXe5esuWuRMn8XIcCBAk1P7VI2Tp b7LRqnUFAOkFf1S9vFB4yiUrtTyNI0eDO0Fr0f1pFEuQbHjKXfeWwhJlRjkcJ/jkiYw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=EP5MTUec; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 181AD606A332; Tue, 3 Nov 2026 02:15:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=EP5MTUec Received: by smtp.kernel.org (Postfix) with ESMTPSA id D65DB1F000C1; Tue, 3 Nov 2026 02:15:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1793672135; bh=81c/CIbeUI49AQeq8U0mWkFHFiq032kJ91gY7TvTAKQ=; h=Date:To:From:Subject; b=EP5MTUeclPHUNixWDa9HtbONA0uf35oIr1HwvYb7KcOVGSm7E+NfXxn74UjeXPurs +zf4v+2dZP6jrvJ+K2H0VYquZ7izQHoXS0F/KIyyvIU8g0hQ/R4i5FCD/U2NS8v1nY 0WOtx9S+cS/8fv+muiyZsq+YbRjc5Llxb8TQEmlc= Date: Mon, 02 Nov 2026 18:15:35 -0800 To: mm-commits@vger.kernel.org,xu.xin@linux.dev,stable@vger.kernel.org, rppt@kernel.org,peterx@redhat.com,lance.yang@linux.dev,kas@kernel.org, david@kernel.org,chengming.zhou@linux.dev,samarth.colleges@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] mm-ksm-keep-soft-dirty-when-merging-a-page.patch removed from -mm tree Message-Id: <20261103021535.D65DB1F000C1@smtp.kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list The quilt patch titled Subject: mm/ksm: keep soft-dirty when merging a page has been removed from the -mm tree. Its filename was mm-ksm-keep-soft-dirty-when-merging-a-page.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Samarth Narang Subject: mm/ksm: keep soft-dirty when merging a page Date: Wed, 21 Oct 2026 11:21:57 -0700 replace_page() maps the KSM page with a PTE built from scratch, so the soft-dirty bit of the PTE it replaces is lost. A page written since "clear_refs 4" then no longer shows as soft-dirty once it is merged, and a soft-dirty based dumper treats it as unchanged. Copy the soft-dirty bit from the original PTE to the new PTE. Link: https://lore.kernel.org/20261021182157.1873726-1-samarth.colleges@gmail.com Fixes: 0f8975ec4db2 ("mm: soft-dirty bits for user memory changes tracking") Signed-off-by: Samarth Narang Signed-off-by: Andrew Morton Reviewed-by: Lance Yang Acked-by: David Hildenbrand (Arm) Assisted-by: LLM Cc: Xu Xin Cc: Chengming Zhou Cc: Peter Xu Cc: Kiryl Shutsemau Cc: Mike Rapoport Cc: --- mm/ksm.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/ksm.c~mm-ksm-keep-soft-dirty-when-merging-a-page +++ a/mm/ksm.c @@ -1463,6 +1463,10 @@ static int replace_page(struct vm_area_s dec_mm_counter(mm, MM_ANONPAGES); } + /* Preserve soft-dirty when replacing the page. */ + if (pte_soft_dirty(orig_pte)) + newpte = pte_mksoft_dirty(newpte); + flush_cache_page(vma, addr, pte_pfn(ptep_get(ptep))); /* * No need to notify as we are replacing a read only page with another _ Patches currently in -mm which might be from samarth.colleges@gmail.com are