WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] Explicit return type for Hypercall

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Explicit return type for Hypercall
From: Tej <bewith.tej@xxxxxxxxx>
Date: Thu, 9 Apr 2009 17:58:37 +0530
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Thu, 09 Apr 2009 05:29:08 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=b9IltBIC/lQjdssDP7lOa6s4rolrKGVBqW4MFJHhWzc=; b=wyR3Jp5vH7fzKiW7g8qpqgdYioVSXXSqOBBCMaeLoSkoli26lEH1YGTxlt9fxD88/8 loorAnf9953ESGLknZ5/NG0BNUGNpIhYUsz01EcbNrFjPAaFnooiqdxm28TpSEp5YAEG 9a78TnAQMF8XIxCJf4wB0tMNSjs+bNNEE8gaI=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=cnV3BKrkFP7nlRRWHfQgo5ltdZazApMeWlz2c6v2cV0QHGIaMW7tspMJjdsaJwPEYW VBp4ne/kBYQNhwhBlSGSMBrUCYQvragYYUChmzQLWtvUvbMNxtyRxr3WPsnqN6goqgJ7 c6BL7R/rF2kqOF+aaKODbxZVUcsK94106Xwac=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <C6039893.84C1%keir.fraser@xxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <f1c9d250904090338j28b44cffh42ade9161eb2ddf0@xxxxxxxxxxxxxx> <C6039893.84C1%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
On Thu, Apr 9, 2009 at 4:50 PM, Keir Fraser <keir.fraser@xxxxxxxxxxxxx> wrote:
> On 09/04/2009 11:38, "Tej" <bewith.tej@xxxxxxxxx> wrote:
>
>> eg in GCOV case, I issued hypercall, when there is no corresponding
>> entry in Hypervisor, it gives -38<3> as return type. and Kernel Send a
>> message to userspace (in case of kernel module) as Kernel does not
>> have module support, which is total misleading.
>
> The return code is ENOSYS, which is appropriate for an unimplemented
> hypercall.

Still it could be misleading, because in case of kernel modules
"module-uti"l packages overrides ENOSYS with message as "Kernel does
not have module support"

an explicit return type could be useful here.

>
>  -- Keir
>
>
>

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel