From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Liu Subject: Re: [PATCH v2 2/3] xc/tmem: Unchecked return value Date: Thu, 08 May 2014 16:47:03 +0800 Message-ID: <536B4487.7020603@oracle.com> References: <1399444250-17529-1-git-send-email-bob.liu@oracle.com> <1399444250-17529-2-git-send-email-bob.liu@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1WiJzA-0008Ts-1g for xen-devel@lists.xenproject.org; Thu, 08 May 2014 08:47:24 +0000 In-Reply-To: <1399444250-17529-2-git-send-email-bob.liu@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Bob Liu Cc: keir@xen.org, ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, andrew.cooper3@citrix.com, ian.jackson@eu.citrix.com, jbeulich@suse.com, xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org CC'd tools maintainers. On 05/07/2014 02:30 PM, Bob Liu wrote: > From: Konrad Rzeszutek Wilk > > CID 1055045 complains that the return value needs checking. > > The tmem op is a flush call and there is no expectation > right now of any return besides zero. But just in case > this changes lets blow up. > > v2: > * superfluous braces and missing space (Andrew) > * Add a comment why bailing out on xc_tmem_save_done is not needed > > Signed-off-by: Konrad Rzeszutek Wilk > Signed-off-by: Bob Liu > --- > tools/libxc/xc_domain_save.c | 6 ++++-- > tools/libxc/xc_tmem.c | 4 ++-- > tools/libxc/xenctrl.h | 2 +- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/tools/libxc/xc_domain_save.c b/tools/libxc/xc_domain_save.c > index 71f9b59..856eaa5 100644 > --- a/tools/libxc/xc_domain_save.c > +++ b/tools/libxc/xc_domain_save.c > @@ -2107,8 +2107,10 @@ int xc_domain_save(xc_interface *xch, int io_fd, uint32_t dom, uint32_t max_iter > goto copypages; > } > > - if ( tmem_saved != 0 && live ) > - xc_tmem_save_done(xch, dom); > + if ( tmem_saved != 0 && live && xc_tmem_save_done(xch, dom) ) > + /* N.B. No need to bail out - we leak memory, but that is all assigned > + * to the zombie guest. */ > + DPRINTF("Warning - failed to flush tmem on originating server."); > > if ( live ) > { > diff --git a/tools/libxc/xc_tmem.c b/tools/libxc/xc_tmem.c > index 6832bbe..250e438 100644 > --- a/tools/libxc/xc_tmem.c > +++ b/tools/libxc/xc_tmem.c > @@ -355,9 +355,9 @@ int xc_tmem_save_extra(xc_interface *xch, int dom, int io_fd, int field_marker) > } > > /* only called for live migration */ > -void xc_tmem_save_done(xc_interface *xch, int dom) > +int xc_tmem_save_done(xc_interface *xch, int dom) > { > - xc_tmem_control(xch,0,TMEMC_SAVE_END,dom,0,0,0,NULL); > + return xc_tmem_control(xch,0,TMEMC_SAVE_END,dom,0,0,0,NULL); > } > > /* restore routines */ > diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h > index 02129f7..23630a7 100644 > --- a/tools/libxc/xenctrl.h > +++ b/tools/libxc/xenctrl.h > @@ -2011,7 +2011,7 @@ int xc_tmem_control(xc_interface *xch, > int xc_tmem_auth(xc_interface *xch, int cli_id, char *uuid_str, int arg1); > int xc_tmem_save(xc_interface *xch, int dom, int live, int fd, int field_marker); > int xc_tmem_save_extra(xc_interface *xch, int dom, int fd, int field_marker); > -void xc_tmem_save_done(xc_interface *xch, int dom); > +int xc_tmem_save_done(xc_interface *xch, int dom); > int xc_tmem_restore(xc_interface *xch, int dom, int fd); > int xc_tmem_restore_extra(xc_interface *xch, int dom, int fd); > > -- Regards, -Bob