From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f74.google.com (mail-ed1-f74.google.com [209.85.208.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B6733911AB for ; Mon, 22 Jun 2026 11:12:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782126743; cv=none; b=HG8L1vuHzd68m4mOLoJhJbddXfOb9HY6jotf84fV4ry0PEgaKPTMlBR0jtKLANTTe0LTyWA6/WqTvQvxArowinPNHi3uYi+OEzrdvfv21f+0BkWf/lys1LWWTFCNlNJEqPgqcAnRvvv45BGhF1o1Tw+66FZsIJ5xve+++vd5cYI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782126743; c=relaxed/simple; bh=USECiQLPaJ6laNGqQsFdCnJP0uDOKvlsmPCoi9r7F/A=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=OYXlHP5RWEMEe3axe15IoFV1JQV6Pbvtgaus9GkyGJ5sJKK16k0uKTK1EnV9DxT6nozQy9C7v6v615jr2kc4+L6Nmd2x8l8v1EDKspuruSg/L8djc2Sl1rk2+xXlPa4pChio4OlqG9xGe9GU30lLXsFDPNSCbnUabwgC2KimpYs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--tarunsahu.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=R39RyScA; arc=none smtp.client-ip=209.85.208.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--tarunsahu.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="R39RyScA" Received: by mail-ed1-f74.google.com with SMTP id 4fb4d7f45d1cf-69576b83dc2so3865384a12.1 for ; Mon, 22 Jun 2026 04:12:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1782126740; x=1782731540; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=YXbPmQmazgkFdDbtyTXXxgi0W9OrSOLs1ojwaV9lxRY=; b=R39RyScAv2svx/c1hM0Tz+glOnrPL4ehZnmgYfULvgzBR73Y0yPcZ0eodjSna1dfjR 6P6x/+9tTYv4CCPJw4L76KmyVmQ7KEGceSijGboRUMSsfQvDhdask3qTl21Bx2G0P0Kc heBUOJuV6N+a3NKlvDF9yoOGWo7W2OleSpc4l26tOb8A2r4bXulEvZzJ3OAEgFZzDInw 85vuqE1T2GU0ca8bzqmsKOxP68/lPn9tWCY/PNpjd5HTSq7JDIjTus6YihDEidIlzOJ0 +7sDgkxU3x5o03OFhf5LtJO501hoplWWU3PipINRBeq9zWemaqPuTj4gQk8m4PCPXuVp qvTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782126740; x=1782731540; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=YXbPmQmazgkFdDbtyTXXxgi0W9OrSOLs1ojwaV9lxRY=; b=kX6MNsvmeqCmY+W41Zu9g7Iz1WjZNoQ7r3hQDcx5JqepPjticGT+39ruHmAyq/APWG 08lJdqSTfU7/J/Ra6TQYo/PL/gQGCD69jcPtBs8M1PDIikcPDviaOw1Mj5GfJB8agrXZ Y6PPPPWzWCOlZdfnnPI650lhVk241BsTOnimNEgzt29ngID4JC5iyo+Hhsu7BQY6veHJ N3nodtPsTUJR5m0YLlUjiDXTXKvQA9a1hUlxKXH7do2wwmJr91YzzGDmxqVD9K0kQ+bT m725Laf1r9q2zjXiIlLpopJ649hM3H3+Dh6fBVqGVEwexxY4WBy2K1QgqIx+yBhCMF+m egYQ== X-Gm-Message-State: AOJu0YzWU9XxhwO911x51wGzonEmEwkD7GfcakGUU3ec724sB99AS96x HwAw8MWUD4+uZLvIslGqbhcVyDtX/NonJdUvLWmbTblSTaLlb24RlBDxWAdgpIcr3hkmKEnbsvA nr98kT7qwfJjvBC8+6A== X-Received: from edai33.prod.google.com ([2002:a05:6402:f21:b0:697:ade6:f966]) (user=tarunsahu job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:5215:b0:696:8f45:4ae7 with SMTP id 4fb4d7f45d1cf-696e5211777mr6088859a12.13.1782126739883; Mon, 22 Jun 2026 04:12:19 -0700 (PDT) Date: Mon, 22 Jun 2026 11:12:15 +0000 In-Reply-To: <20260622111215.4157974-1-tarunsahu@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260622111215.4157974-1-tarunsahu@google.com> X-Mailer: git-send-email 2.55.0.rc0.738.g0c8ab3ebcc-goog Message-ID: <20260622111215.4157974-3-tarunsahu@google.com> Subject: [REESND PATCH v3 2/2] luo: Update serialized data to use KHOSER_PTR From: Tarun Sahu To: Andrew Morton , Pasha Tatashin , Alexander Graf , Pratyush Yadav , Mike Rapoport Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-mm@kvack.org, Tarun Sahu Content-Type: text/plain; charset="UTF-8" Convert raw serialized_data to KHO serializeable pointer (KHOSER_PTR). This series also takes care of resolving the bug with memfd of using phys_to_virt before checking the args->serialized_data value. Fixes: b3749f174d68 ("mm: memfd_luo: allow preserving memfd") Signed-off-by: Tarun Sahu --- include/linux/kho/abi/luo.h | 5 +++-- include/linux/liveupdate.h | 4 ++-- kernel/liveupdate/luo_file.c | 24 ++++++++++++------------ mm/memfd_luo.c | 18 +++++++++--------- 4 files changed, 26 insertions(+), 25 deletions(-) diff --git a/include/linux/kho/abi/luo.h b/include/linux/kho/abi/luo.h index 288076de6d4a..d5b3b1c0fec1 100644 --- a/include/linux/kho/abi/luo.h +++ b/include/linux/kho/abi/luo.h @@ -59,6 +59,7 @@ #include #include +#include #include /* @@ -89,14 +90,14 @@ struct luo_ser { /** * struct luo_file_ser - Represents the serialized preserves files. * @compatible: File handler compatible string. - * @data: Private data + * @serialized_data: The serialized pointer union for this file * @token: User provided token for this file * * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated. */ struct luo_file_ser { char compatible[LIVEUPDATE_HNDL_COMPAT_LENGTH]; - u64 data; + DECLARE_KHOSER_PTR(serialized_data, void *); u64 token; } __packed; diff --git a/include/linux/liveupdate.h b/include/linux/liveupdate.h index 88722e5caf02..480d638b7d18 100644 --- a/include/linux/liveupdate.h +++ b/include/linux/liveupdate.h @@ -33,7 +33,7 @@ struct file; * @file: The file object. For retrieve: [OUT] The callback sets * this to the new file. For other ops: [IN] The caller sets * this to the file being operated on. - * @serialized_data: The opaque u64 handle, preserve/prepare/freeze may update + * @serialized_data: The serialized pointer union, preserve/prepare/freeze may update * this field. * @private_data: Private data for the file used to hold runtime state that * is not preserved. Set by the handler's .preserve() @@ -47,7 +47,7 @@ struct liveupdate_file_op_args { struct liveupdate_file_handler *handler; int retrieve_status; struct file *file; - u64 serialized_data; + DECLARE_KHOSER_PTR(serialized_data, void *); void *private_data; }; diff --git a/kernel/liveupdate/luo_file.c b/kernel/liveupdate/luo_file.c index c39f96961a85..79cfa5201899 100644 --- a/kernel/liveupdate/luo_file.c +++ b/kernel/liveupdate/luo_file.c @@ -125,7 +125,7 @@ static DEFINE_XARRAY(luo_preserved_files); * @file: Pointer to the kernel's &struct file that is being preserved. * This is NULL in the new kernel until the file is successfully * retrieved. - * @serialized_data: The opaque u64 handle to the serialized state of the file. + * @serialized_data: The serialized pointer union to the serialized state of the file. * This handle is passed back to the handler's .freeze(), * .retrieve(), and .finish() callbacks, allowing it to track * and update its serialized state across phases. @@ -161,7 +161,7 @@ static DEFINE_XARRAY(luo_preserved_files); struct luo_file { struct liveupdate_file_handler *fh; struct file *file; - u64 serialized_data; + DECLARE_KHOSER_PTR(serialized_data, void *); void *private_data; int retrieve_status; struct mutex mutex; @@ -289,7 +289,7 @@ int luo_preserve_file(struct luo_file_set *file_set, u64 token, int fd) if (err) goto err_kfree; - luo_file->serialized_data = args.serialized_data; + KHOSER_COPY_TYPESAFE(luo_file->serialized_data, args.serialized_data); luo_file->private_data = args.private_data; list_add_tail(&luo_file->list, &file_set->files_list); file_set->count++; @@ -342,7 +342,7 @@ void luo_file_unpreserve_files(struct luo_file_set *file_set) args.handler = luo_file->fh; args.file = luo_file->file; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); args.private_data = luo_file->private_data; luo_file->fh->ops->unpreserve(&args); luo_flb_file_unpreserve(luo_file->fh); @@ -375,12 +375,12 @@ static int luo_file_freeze_one(struct luo_file_set *file_set, args.handler = luo_file->fh; args.file = luo_file->file; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); args.private_data = luo_file->private_data; err = luo_file->fh->ops->freeze(&args); if (!err) - luo_file->serialized_data = args.serialized_data; + KHOSER_COPY_TYPESAFE(luo_file->serialized_data, args.serialized_data); } return err; @@ -396,7 +396,7 @@ static void luo_file_unfreeze_one(struct luo_file_set *file_set, args.handler = luo_file->fh; args.file = luo_file->file; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); args.private_data = luo_file->private_data; luo_file->fh->ops->unfreeze(&args); @@ -483,7 +483,7 @@ int luo_file_freeze(struct luo_file_set *file_set, strscpy(file_ser->compatible, luo_file->fh->compatible, sizeof(file_ser->compatible)); - file_ser->data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(file_ser->serialized_data, luo_file->serialized_data); file_ser->token = luo_file->token; } @@ -587,7 +587,7 @@ int luo_retrieve_file(struct luo_file_set *file_set, u64 token, } args.handler = luo_file->fh; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); err = luo_file->fh->ops->retrieve(&args); if (err) { /* Keep the error code for later use. */ @@ -621,7 +621,7 @@ static int luo_file_can_finish_one(struct luo_file_set *file_set, args.handler = luo_file->fh; args.file = luo_file->file; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); args.retrieve_status = luo_file->retrieve_status; can_finish = luo_file->fh->ops->can_finish(&args); } @@ -638,7 +638,7 @@ static void luo_file_finish_one(struct luo_file_set *file_set, args.handler = luo_file->fh; args.file = luo_file->file; - args.serialized_data = luo_file->serialized_data; + KHOSER_COPY_TYPESAFE(args.serialized_data, luo_file->serialized_data); args.retrieve_status = luo_file->retrieve_status; luo_file->fh->ops->finish(&args); @@ -748,7 +748,7 @@ static int luo_file_deserialize_one(struct luo_file_set *file_set, luo_file->fh = fh; luo_file->file = NULL; - luo_file->serialized_data = ser->data; + KHOSER_COPY_TYPESAFE(luo_file->serialized_data, ser->serialized_data); luo_file->token = ser->token; mutex_init(&luo_file->mutex); list_add_tail(&luo_file->list, &file_set->files_list); diff --git a/mm/memfd_luo.c b/mm/memfd_luo.c index 59de210bee5f..daf2c4c3da35 100644 --- a/mm/memfd_luo.c +++ b/mm/memfd_luo.c @@ -257,6 +257,7 @@ static void memfd_luo_unpreserve_folios(struct kho_vmalloc *kho_vmalloc, static int memfd_luo_preserve(struct liveupdate_file_op_args *args) { + DECLARE_KHOSER_PTR(sd, struct memfd_luo_ser *); struct inode *inode = file_inode(args->file); struct memfd_luo_folio_ser *folios_ser; struct memfd_luo_ser *ser; @@ -309,7 +310,8 @@ static int memfd_luo_preserve(struct liveupdate_file_op_args *args) inode_unlock(inode); args->private_data = folios_ser; - args->serialized_data = virt_to_phys(ser); + KHOSER_STORE_PTR(sd, ser); + KHOSER_COPY_TYPEUNSAFE(args->serialized_data, sd); return 0; @@ -325,11 +327,10 @@ static int memfd_luo_freeze(struct liveupdate_file_op_args *args) { struct memfd_luo_ser *ser; - if (WARN_ON_ONCE(!args->serialized_data)) + ser = KHOSER_LOAD_PTR(args->serialized_data); + if (WARN_ON_ONCE(!ser)) return -EINVAL; - ser = phys_to_virt(args->serialized_data); - /* * The pos might have changed since prepare. Everything else stays the * same. @@ -344,14 +345,13 @@ static void memfd_luo_unpreserve(struct liveupdate_file_op_args *args) struct inode *inode = file_inode(args->file); struct memfd_luo_ser *ser; - if (WARN_ON_ONCE(!args->serialized_data)) + ser = KHOSER_LOAD_PTR(args->serialized_data); + if (WARN_ON_ONCE(!ser)) return; inode_lock(inode); shmem_freeze(inode, false); - ser = phys_to_virt(args->serialized_data); - memfd_luo_unpreserve_folios(&ser->folios, args->private_data, ser->nr_folios); @@ -397,7 +397,7 @@ static void memfd_luo_finish(struct liveupdate_file_op_args *args) if (args->retrieve_status) return; - ser = phys_to_virt(args->serialized_data); + ser = KHOSER_LOAD_PTR(args->serialized_data); if (!ser) return; @@ -522,7 +522,7 @@ static int memfd_luo_retrieve(struct liveupdate_file_op_args *args) struct file *file; int err; - ser = phys_to_virt(args->serialized_data); + ser = KHOSER_LOAD_PTR(args->serialized_data); if (!ser) return -EINVAL; -- 2.55.0.rc0.738.g0c8ab3ebcc-goog