From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79F1C3DEFE0; Wed, 1 Apr 2026 17:37:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775065039; cv=none; b=aTBdIWoOt0X/t4vGtkw63OGieQnr8QCRTMwBhC/rHzslAeOowLZTkvceYxqley1LC/rea08etz/xwEXNhFANtuD6Ou9EHXsbQAcJsZcu3C53VBnXTAUXlKzhwQPkTSmBLImBuhG9Y8obaUatkcn6RGFWkTL/RlfPmYC/CqJ2gBw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775065039; c=relaxed/simple; bh=QmcnS3tunksGoYi+iCesvBhUK2kH7XFD5ftcMv/BXsQ=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=ZOjyMh2ZueRzI3mBM98rncZkFm1otapyIJLPdt2uCeF2GjsLoPaPtZTA1lW4UUZ6iC/oqb5FawnjfVzyx7Waa8LHg49mCA8/MhMg+Y05rqv7NzVDkdD1llM56+CrM/Ba+TcicwGtWTSHAR0/z6Dq3APiLJLRgBmmBJ9qAqwK2As= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=mwIDp6FB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="mwIDp6FB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3F657C4CEF7; Wed, 1 Apr 2026 17:37:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1775065039; bh=QmcnS3tunksGoYi+iCesvBhUK2kH7XFD5ftcMv/BXsQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=mwIDp6FByrI4mxsw47udOkD5cNG1MxeD1cHCBXZY1mgNVQC8np/HoYpcQ8mz4shaf fRI/wvkzpdKYrIa6qQfjJdLevmo5IzBMNee9Q4H4YzcWhb3D/LKSjw7w0dfEJNCDSV xH1xXd+gw3c+bBphnXqjNNoPmOMD++IpR0ThjHfo= Date: Wed, 1 Apr 2026 10:37:17 -0700 From: Andrew Morton To: Mike Rapoport Cc: "Harry Yoo (Oracle)" , Andrea Arcangeli , Andrei Vagin , Axel Rasmussen , Baolin Wang , David Hildenbrand , Hugh Dickins , James Houghton , "Liam R. Howlett" , "Lorenzo Stoakes (Oracle)" , "Matthew Wilcox (Oracle)" , Michal Hocko , Muchun Song , Nikita Kalyazin , Oscar Salvador , Paolo Bonzini , Peter Xu , Sean Christopherson , Shuah Khan , Suren Baghdasaryan , Vlastimil Babka , kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3 02/15] userfaultfd: introduce struct mfill_state Message-Id: <20260401103717.b236b271a2856d536a48663b@linux-foundation.org> In-Reply-To: References: <20260330101116.1117699-1-rppt@kernel.org> <20260330101116.1117699-3-rppt@kernel.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 1 Apr 2026 10:36:03 +0300 Mike Rapoport wrote: > Here's a fixup (it causes a conflict in patch 4 though). > Andrew, I can send v4 if you prefer. Looks pretty simple. "userfaultfd: introduce mfill_get_vma() and mfill_put_vma()" now leaves things like this: retry: err = mfill_get_vma(&state); if (err) goto out; state.vma = dst_vma; /* * If this is a HUGETLB vma, pass off to appropriate routine */ if (is_vm_hugetlb_page(state.vma)) return mfill_atomic_hugetlb(ctx, state.vma, dst_start, src_start, len, flags); while (state.src_addr < src_start + len) { VM_WARN_ON_ONCE(state.dst_addr >= dst_start + len); err = mfill_establish_pmd(&state); if (err) break; /* * For shmem mappings, khugepaged is allowed to remove page * tables under us; pte_offset_map_lock() will deal with that. */ err = mfill_atomic_pte(&state); cond_resched(); if (unlikely(err == -ENOENT)) { void *kaddr; mfill_put_vma(&state); VM_WARN_ON_ONCE(!state.folio); kaddr = kmap_local_folio(state.folio, 0); err = copy_from_user(kaddr, (const void __user *)state.src_addr, PAGE_SIZE); kunmap_local(kaddr); if (unlikely(err)) { err = -EFAULT; goto out; } flush_dcache_folio(state.folio); goto retry; } else VM_WARN_ON_ONCE(state.folio); if (!err) { state.dst_addr += PAGE_SIZE; state.src_addr += PAGE_SIZE; copied += PAGE_SIZE; if (fatal_signal_pending(current)) err = -EINTR; } if (err) break; }