From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nikolaus Voss Subject: RE: [PATCH v2 1/3] ACPI: Resolve objects on host-directed table loads Date: Mon, 17 Jun 2019 08:24:18 +0200 (CEST) Message-ID: References: <94F2FBAB4432B54E8AACC7DFDE6C92E3B95EFB26@ORSMSX110.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Return-path: In-Reply-To: <94F2FBAB4432B54E8AACC7DFDE6C92E3B95EFB26@ORSMSX110.amr.corp.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: "Moore, Robert" Cc: "Rafael J. Wysocki" , "Rafael J. Wysocki" , Len Brown , "Schmauss, Erik" , Jacek Anaszewski , Pavel Machek , Dan Murphy , Thierry Reding , ACPI Devel Maling List , "open list:ACPI COMPONENT ARCHITECTURE (ACPICA)" , "linux-leds@vger.kernel.org" , Linux PWM List , Linux Kernel Mailing List , nikolaus.voss@loewensteinmedical.de List-Id: linux-leds@vger.kernel.org Bob, On Fri, 14 Jun 2019, Moore, Robert wrote: > > > -----Original Message----- > From: Nikolaus Voss [mailto:nv@vosn.de] > Sent: Friday, June 14, 2019 2:26 AM > To: Rafael J. Wysocki > Cc: Rafael J. Wysocki ; Len Brown ; Moore, Robert ; Schmauss, Erik ; Jacek Anaszewski ; Pavel Machek ; Dan Murphy ; Thierry Reding ; ACPI Devel Maling List ; open list:ACPI COMPONENT ARCHITECTURE (ACPICA) ; linux-leds@vger.kernel.org; Linux PWM List ; Linux Kernel Mailing List > Subject: Re: [PATCH v2 1/3] ACPI: Resolve objects on host-directed table loads > > Hi Rafael, > > On Fri, 14 Jun 2019, Rafael J. Wysocki wrote: >> On Wed, Jun 12, 2019 at 10:36 AM Nikolaus Voss >> wrote: >>> >>> If an ACPI SSDT overlay is loaded after built-in tables have been >>> loaded e.g. via configfs or efivar_ssdt_load() it is necessary to >>> rewalk the namespace to resolve references. Without this, relative >>> and absolute paths like ^PCI0.SBUS or \_SB.PCI0.SBUS are not resolved >>> correctly. >>> >>> Make configfs load use the same method as efivar_ssdt_load(). >>> >>> Signed-off-by: Nikolaus Voss >> >> This is fine by me, so >> >> Acked-by: Rafael J. Wysocki >> >> Or if you want me to take this patch (without the other two in the >> series), please let me know. > > thanks. I think it would be the best if you take up this patch as it is > an independent topic. In retrospect it wasn't a good idea to put it into > this series. > > Kind regards, > Niko > > I would have to ask, why is additional code needed for package > initialization/resolution? It already happens elsewhere in acpica. Bob for built-in tables loaded via acpi_ex_load_table_op() everything is fine, because after acpi_tb_load_table() acpi_ns_walk_namespace() is called to resolve references. My fix only affects tables loaded dynamically via either acpi_configfs driver (for debugging purposes) or efivar_ssdt_load() (to specify a table on the kernel's command line). They use acpi_load_table() to load the table from a caller-owned buffer. To resolve the references, it is again necessary to rewalk the namespace, which was simply missing in acpi_load_table(). Niko