From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44127) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fIxTt-0007Bl-33 for qemu-devel@nongnu.org; Wed, 16 May 2018 10:32:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fIxTq-0002iV-0W for qemu-devel@nongnu.org; Wed, 16 May 2018 10:32:41 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52052 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 1fIxTp-0002i5-RU for qemu-devel@nongnu.org; Wed, 16 May 2018 10:32:37 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BB0B540201A1 for ; Wed, 16 May 2018 14:32:36 +0000 (UTC) Date: Wed, 16 May 2018 16:32:34 +0200 From: Igor Mammedov Message-ID: <20180516163234.79a6e692@redhat.com> In-Reply-To: <87eficu8g1.fsf@dusky.pond.sub.org> References: <1526395713-60357-1-git-send-email-imammedo@redhat.com> <20180515152641.7oaxop77wgzokr7h@kamzik.brq.redhat.com> <3543e1cb-85b9-7f50-f97f-e8f2b98b10e0@redhat.com> <87eficu8g1.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] numa: clarify error message when node index is out of range in -numa dist, ... List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Eric Blake , Andrew Jones , qemu-devel@nongnu.org, ehabkost@redhat.com On Tue, 15 May 2018 19:37:02 +0200 Markus Armbruster wrote: > Eric Blake writes: > > > On 05/15/2018 10:26 AM, Andrew Jones wrote: > >> On Tue, May 15, 2018 at 04:48:33PM +0200, Igor Mammedov wrote: > >>> When using following CLI: > >>> -numa dist,src=128,dst=1,val=20 > >>> user gets a rather confusing error message: > >>> "Invalid node 128, max possible could be 128" > >>> > >>> Where 128 is number of nodes that QEMU supports (MAX_NODES), > >>> while src/dst is an index up to that limit, so it should be > >>> MAX_NODES - 1 in error message. > >>> Make error message to explicitly state valid range for node > >>> index to be more clear. > >>> > >>> Signed-off-by: Igor Mammedov > >>> Reviewed-by: Andrew Jones > >>> --- > > > >>> if (src >= MAX_NODES || dst >= MAX_NODES) { > >>> error_setg(errp, > >>> - "Invalid node %d, max possible could be %d", > >>> - MAX(src, dst), MAX_NODES); > >>> + "Invalid node %d, The valid node range is [0 - %d]", > >> ^ should be a '.' > >> > >> And maybe need a '.' at the end of the second sentence too, as it's not > >> an error phrase, but a real sentence. > >> > >>> + MAX(src, dst), MAX_NODES - 1); > >>> return; > >>> } > > > > Actually, error_setg() is documented as taking a single phrase (no '.' > > included), and that if you need a second sentence, it's better to use > > error_append_hint(). well, using append_hint makes it less readable, before using it we get following error: $ qemu-system-x86_64 -numa dist,src=128,dst=1,val=20 qemu-system-x86_64: -numa dist,src=128,dst=1,val=20: Invalid node 128, The valid node range is [0 - 127] $ after using it we get: $ qemu-system-x86_64 -numa dist,src=128,dst=1,val=20 qemu-system-x86_64: -numa dist,src=128,dst=1,val=20: Invalid node value 128 The valid node range is [0 - 127]$ i.e. an extra newline in the middle of error message and looses automatic newline at the end so the shell prompt continues error message > Correct. Providing help on valid values is exactly what > error_append_hint() is for. > > > Maybe Markus has an opinion on the best way to > > word this error message. > > Yes: "Parameter 'src' expects an integer between 0 and 127" > > Referring to an erroneous key=value by value is not nice. What if the > value occurs in multiple places, and is valid in at least one? key is > there, it's unique[*], so use it. > > > [*] Except in the few places that use repeated keys to form lists. Ugh.