From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38795) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fLVzD-0004tq-On for qemu-devel@nongnu.org; Wed, 23 May 2018 11:47:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fLVz9-0002rn-1P for qemu-devel@nongnu.org; Wed, 23 May 2018 11:47:35 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:49580 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fLVz8-0002rP-Tn for qemu-devel@nongnu.org; Wed, 23 May 2018 11:47:30 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 67E55818BAF8 for ; Wed, 23 May 2018 15:47:30 +0000 (UTC) References: <20180522035629.30428-1-peterx@redhat.com> <20180522035629.30428-2-peterx@redhat.com> From: Eric Blake Message-ID: <101fcf93-23b4-a628-13cd-8cb2a169fbc4@redhat.com> Date: Wed, 23 May 2018 10:47:29 -0500 MIME-Version: 1.0 In-Reply-To: <20180522035629.30428-2-peterx@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 1/2] qemu-error: introduce {error|warn}_report_once List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu , qemu-devel@nongnu.org Cc: Jason Wang , Markus Armbruster , "Michael S . Tsirkin" On 05/21/2018 10:56 PM, Peter Xu wrote: > I stole the printk_once() macro. > > I always wanted to be able to print some error directly if there is a > buffer to dump, however we can't use error_report() where the code path > can be triggered by DDOS attack. To avoid that, we can introduce a > print-once-like function for it. Meanwhile, we also introduce the > corresponding helper for warn_report(). > > CC: Markus Armbruster > Signed-off-by: Peter Xu > --- > include/qemu/error-report.h | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/include/qemu/error-report.h b/include/qemu/error-report.h > index e1c8ae1a52..3e6e84801f 100644 > --- a/include/qemu/error-report.h > +++ b/include/qemu/error-report.h > @@ -44,6 +44,32 @@ void error_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > void warn_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > void info_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > > +/* Similar to error_report(), but it only prints the message once. */ > +#define error_report_once(fmt, ...) \ > + ({ \ > + static bool __print_once; \ You're still using the reserved namespace. I asked you to fix that on v1; it's disappointing when a later revision doesn't make changes requested by a reviewers, without also offering a counter-argument for why the request does not need to be considered. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org