From owner-freebsd-dtrace@freebsd.org Thu May 18 23:52:18 2017 Return-Path: Delivered-To: freebsd-dtrace@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 5B9B7D73E2C for ; Thu, 18 May 2017 23:52:18 +0000 (UTC) (envelope-from markjdb@gmail.com) Received: from mail-qk0-x22f.google.com (mail-qk0-x22f.google.com [IPv6:2607:f8b0:400d:c09::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 0F1A51A33 for ; Thu, 18 May 2017 23:52:18 +0000 (UTC) (envelope-from markjdb@gmail.com) Received: by mail-qk0-x22f.google.com with SMTP id k74so49557570qke.1 for ; Thu, 18 May 2017 16:52:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=3DkVmaL9+f8aV6dIKT0zq0htTEWlQbKWsg163VLGavk=; b=fRIGwp0M01OLKpIsxE6ZzxAEWKoWQV4S6pFyB4cucdzE0CRj9TOCrIVYt1TT4Jdywc cMENWcCZ3RgtOTFT7oNGnTvcKaCx4u/Q0arv4n5CoDrJrsXyLmYtN80L+MUDCYIhEVMj XWHCHG2ahuvE0Gg2Sa7IQSVTdYkQtHPiLEZlsQZChn8UqT3AbGuztk93mZDX5OPEL4BM MosBx5hFlbPvqHCu2M7lwmCxky/z1BtUDvFafX4GUwHlhppTUUCTyfZj1R0+HU6+c8Ez 9XGbKzo7jKPMc6H3Ty5TiPXnISzI0pd2ynJ7A3wbbtV7+/y7xO6D9hQajNlnERerKBUk VwLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=3DkVmaL9+f8aV6dIKT0zq0htTEWlQbKWsg163VLGavk=; b=dgKpwOaZ2yYzICbvMv9dqNPjbSDIIrmJpNAtZMfXshOD2KUk6HxOSyyCobdyT3KgVP lei7Iy/G5p2+JpOAisK16aMVjl9Z15096grB7W8zUUb2JV+8xczRms8M8pQMvrwvMxnZ OXhN9UJP8Sf924YHlm2T/FULWZc90wM7wSeHVDMiv3DHGGtnJCLTT615ul/YgkWQxnUK evWA2PfoUsyB9mRtd4s3/SuWhY5kZea5mWaCuuDEMaT2A1FqncE38udR2PZUIe+WofcL pinohKmranj4Cg8Kv/7xnsnPv2Xk8N5nY8P4YNUadwCyMqoCGDVBVHj4NwVrFnIXibOQ yBSw== X-Gm-Message-State: AODbwcCrpGLZZoBxMKKP9AS32wIiskuGeCVGLyRz6iaCmZLeigr36Tm1 Oh4tIfAkZ+Hk4Q== X-Received: by 10.55.123.2 with SMTP id w2mr6185066qkc.13.1495151537138; Thu, 18 May 2017 16:52:17 -0700 (PDT) Received: from wkstn-mjohnston.west.isilon.com (c-76-104-201-218.hsd1.wa.comcast.net. [76.104.201.218]) by smtp.gmail.com with ESMTPSA id u19sm4743728qtc.64.2017.05.18.16.52.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 18 May 2017 16:52:16 -0700 (PDT) Date: Thu, 18 May 2017 16:52:07 -0700 From: Mark Johnston To: Domagoj Stolfa Cc: Samuel Lepetit , Andreas Longwitz , freebsd-dtrace@freebsd.org Subject: Re: fbt:kernel:breadn_flags:entry): invalid address (0x0) in action #7 Message-ID: <20170518235207.GB37643@wkstn-mjohnston.west.isilon.com> References: <591E01F5.8080208@incore.de> <6A020677-BC76-41E1-8372-10B7962F4EDE@apple.com> <20170518204534.GA37126@wraith> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170518204534.GA37126@wraith> User-Agent: Mutt/1.8.2 (2017-04-18) X-BeenThere: freebsd-dtrace@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "A discussion list for developers working on DTrace in FreeBSD." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 May 2017 23:52:18 -0000 On Thu, May 18, 2017 at 10:45:34PM +0200, Domagoj Stolfa wrote: > Hello, > > > I suspect the easiest way here is just to check that your credential in args[6] is non-null in a predicate. > > yes, you would likely have to enable the probe twice -- once with a non-null > argument and once with a null argument (if required). On FreeBSD head you can also use if-statements. :) fbt:kernel:breadn_flags:entry { if (args[6] != NULL) { ... } else { ... } }