From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx110.postini.com [74.125.245.110]) by kanga.kvack.org (Postfix) with SMTP id 3A7846B006C for ; Sat, 6 Apr 2013 13:37:17 -0400 (EDT) Received: by mail-oa0-f52.google.com with SMTP id k14so4874986oag.39 for ; Sat, 06 Apr 2013 10:37:16 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <515FF3CC.80106@gmail.com> References: <515FF3CC.80106@gmail.com> From: KOSAKI Motohiro Date: Sat, 6 Apr 2013 13:36:56 -0400 Message-ID: Subject: Re: [PATCH 4/4] fsfreeze: avoid to return zero in __get_user_pages Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Marco Stornelli Cc: Linux FS Devel , Mike Snitzer , Alasdair G Kergon , "linux-mm@kvack.org" , LKML , Jan Kara On Sat, Apr 6, 2013 at 6:07 AM, Marco Stornelli wrote: > In case of VM_FAULT_RETRY, __get_user_pages returns the number > of pages alredy gotten, but there isn't a check if this number is > zero. Instead, we have to return a proper error code so we can avoid > a possible extra call of __get_user_pages. There are several > places where get_user_pages is called inside a loop until all the > pages requested are gotten or an error code is returned. > > Signed-off-by: Marco Stornelli > --- > mm/memory.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/mm/memory.c b/mm/memory.c > index 494526a..cca14ed 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -1858,7 +1858,7 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, > if (ret & VM_FAULT_RETRY) { > if (nonblocking) > *nonblocking = 0; > - return i; > + return i ? i : -ERESTARTSYS; nonblock argument is only used from __mm_populate() and it expect __get_user_pages() return 0. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org