From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9555C46CA3 for ; Sat, 2 Dec 2023 08:05:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229854AbjLBICD (ORCPT ); Sat, 2 Dec 2023 03:02:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56810 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229379AbjLBICB (ORCPT ); Sat, 2 Dec 2023 03:02:01 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 90FE5116; Sat, 2 Dec 2023 00:02:06 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3A0281FB; Sat, 2 Dec 2023 00:02:52 -0800 (PST) Received: from [10.57.73.130] (unknown [10.57.73.130]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 96FA23F6C4; Sat, 2 Dec 2023 00:02:02 -0800 (PST) Message-ID: <69a197cf-1e2c-4f6e-b0ca-7cbb154c044b@arm.com> Date: Sat, 2 Dec 2023 08:02:01 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 5/5] selftests/mm: add UFFDIO_MOVE ioctl test Content-Language: en-GB To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, viro@zeniv.linux.org.uk, brauner@kernel.org, shuah@kernel.org, aarcange@redhat.com, lokeshgidra@google.com, peterx@redhat.com, david@redhat.com, hughd@google.com, mhocko@suse.com, axelrasmussen@google.com, rppt@kernel.org, willy@infradead.org, Liam.Howlett@oracle.com, jannh@google.com, zhangpeng362@huawei.com, bgeffon@google.com, kaleshsingh@google.com, ngeoffray@google.com, jdduke@google.com, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-team@android.com References: <20231121171643.3719880-1-surenb@google.com> <20231121171643.3719880-6-surenb@google.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/12/2023 16:26, Suren Baghdasaryan wrote: > On Fri, Dec 1, 2023 at 1:29 AM Ryan Roberts wrote: >> >> On 21/11/2023 17:16, Suren Baghdasaryan wrote: >>> Add tests for new UFFDIO_MOVE ioctl which uses uffd to move source >>> into destination buffer while checking the contents of both after >>> the move. After the operation the content of the destination buffer >>> should match the original source buffer's content while the source >>> buffer should be zeroed. Separate tests are designed for PMD aligned and >>> unaligned cases because they utilize different code paths in the kernel. >>> >>> Signed-off-by: Suren Baghdasaryan >>> --- >>> tools/testing/selftests/mm/uffd-common.c | 24 +++ >>> tools/testing/selftests/mm/uffd-common.h | 1 + >>> tools/testing/selftests/mm/uffd-unit-tests.c | 189 +++++++++++++++++++ >>> 3 files changed, 214 insertions(+) >>> >>> diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c >>> index fb3bbc77fd00..b0ac0ec2356d 100644 >>> --- a/tools/testing/selftests/mm/uffd-common.c >>> +++ b/tools/testing/selftests/mm/uffd-common.c >>> @@ -631,6 +631,30 @@ int copy_page(int ufd, unsigned long offset, bool wp) >>> return __copy_page(ufd, offset, false, wp); >>> } >>> >>> +int move_page(int ufd, unsigned long offset, unsigned long len) >>> +{ >>> + struct uffdio_move uffdio_move; >>> + >>> + if (offset + len > nr_pages * page_size) >>> + err("unexpected offset %lu and length %lu\n", offset, len); >>> + uffdio_move.dst = (unsigned long) area_dst + offset; >>> + uffdio_move.src = (unsigned long) area_src + offset; >>> + uffdio_move.len = len; >>> + uffdio_move.mode = UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES; >>> + uffdio_move.move = 0; >>> + if (ioctl(ufd, UFFDIO_MOVE, &uffdio_move)) { >>> + /* real retval in uffdio_move.move */ >>> + if (uffdio_move.move != -EEXIST) >>> + err("UFFDIO_MOVE error: %"PRId64, >>> + (int64_t)uffdio_move.move); >> >> Hi Suren, >> >> FYI this error is triggering in mm-unstable (715b67adf4c8): >> >> Testing move-pmd on anon... ERROR: UFFDIO_MOVE error: -16 (errno=16, >> @uffd-common.c:648) >> >> I'm running in a VM on Apple M2 (arm64). I haven't debugged any further, but >> happy to go deeper if you can direct. > > Hi Ryan, > Thanks for reporting! Could you please share your kernel config file? It's arm64 defconfig (so 4K base pages) plus: # Squashfs for snaps, xfs for large file folios. ./scripts/config --enable CONFIG_SQUASHFS_LZ4 ./scripts/config --enable CONFIG_SQUASHFS_LZO ./scripts/config --enable CONFIG_SQUASHFS_XZ ./scripts/config --enable CONFIG_SQUASHFS_ZSTD ./scripts/config --enable CONFIG_XFS_FS # Useful trace features (on for Ubuntu configs). ./scripts/config --enable CONFIG_FTRACE ./scripts/config --enable CONFIG_FUNCTION_TRACER ./scripts/config --enable CONFIG_KPROBES ./scripts/config --enable CONFIG_HIST_TRIGGERS ./scripts/config --enable CONFIG_FTRACE_SYSCALLS # For general mm debug. ./scripts/config --enable CONFIG_DEBUG_VM ./scripts/config --enable CONFIG_DEBUG_VM_MAPLE_TREE ./scripts/config --enable CONFIG_DEBUG_VM_RB ./scripts/config --enable CONFIG_DEBUG_VM_PGFLAGS ./scripts/config --enable CONFIG_DEBUG_VM_PGTABLE ./scripts/config --enable CONFIG_PAGE_TABLE_CHECK # For mm selftests. ./scripts/config --enable CONFIG_USERFAULTFD ./scripts/config --enable CONFIG_TEST_VMALLOC ./scripts/config --enable CONFIG_GUP_TEST This is the config I always use when running mm selftests. I'll send you the config file separately. Then I'm running in a QEMU VM with 12G RAM, equally split across 2 (emulated) numa nodes. I have these pertinent kernel command line args (intended to ensure all the mm selftests can run): transparent_hugepage=madvise secretmem.enable hugepagesz=1G hugepages=0:2,1:2 hugepagesz=32M hugepages=0:2,1:2 default_hugepagesz=2M hugepages=0:64,1:64 hugepagesz=64K hugepages=0:2,1:2 > > There are several places UFFDIO_MOVE returns EBUSY: 4 places in > move_pages_huge_pmd(), 2 places in move_present_pte(), 2 places in > move_pages_pte() and once in move_swap_pte(). While I'm trying to > reproduce, it would be useful if you could check which place is > triggering the error. Happy to, but will have to wait for Monday. I should say, the test fails consistently for me. But sometimes the failure is EAGAIN (11). Most of the time it is EBUSY though and I haven't figured out what causes the difference. > Thanks, > Suren. > >> >> Thanks, >> Ryan >> >> >>> + wake_range(ufd, uffdio_move.dst, len); >>> + } else if (uffdio_move.move != len) { >>> + err("UFFDIO_MOVE error: %"PRId64, (int64_t)uffdio_move.move); >>> + } else >>> + return 1; >>> + return 0; >>> +} >> >> -- >> To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com. >>