Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-08 Thread Takashi Iwai
On Thu, 08 Apr 2021 18:56:06 +0200, Ville Syrjälä wrote: > > On Thu, Apr 08, 2021 at 06:34:06PM +0200, Takashi Iwai wrote: > > On Thu, 08 Apr 2021 09:51:18 +0200, > > Takashi Iwai wrote: > > > > > > On Wed, 07 Apr 2021 23:28:48 +0200, > > > Ville Syrjälä wrote: > > > > > > > > Oh, could you ask

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-08 Thread Ville Syrjälä
On Thu, Apr 08, 2021 at 06:34:06PM +0200, Takashi Iwai wrote: > On Thu, 08 Apr 2021 09:51:18 +0200, > Takashi Iwai wrote: > > > > On Wed, 07 Apr 2021 23:28:48 +0200, > > Ville Syrjälä wrote: > > > > > > Oh, could you ask the bug reporter to attach an acpidump to the > > > bug? Might be good to ha

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-08 Thread Takashi Iwai
On Thu, 08 Apr 2021 09:51:18 +0200, Takashi Iwai wrote: > > On Wed, 07 Apr 2021 23:28:48 +0200, > Ville Syrjälä wrote: > > > > Oh, could you ask the bug reporter to attach an acpidump to the > > bug? Might be good to have that stuff on record somewhere if/when > > someone wants to actually figure

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-08 Thread Takashi Iwai
On Wed, 07 Apr 2021 23:28:48 +0200, Ville Syrjälä wrote: > > On Wed, Apr 07, 2021 at 06:56:15PM +0200, Takashi Iwai wrote: > > On Wed, 07 Apr 2021 18:34:46 +0200, > > Ville Syrjälä wrote: > > > > > > On Fri, Apr 02, 2021 at 10:23:17AM +0200, Takashi Iwai wrote: > > > > intel_dsm_platform_mux_info

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-07 Thread Ville Syrjälä
On Wed, Apr 07, 2021 at 06:56:15PM +0200, Takashi Iwai wrote: > On Wed, 07 Apr 2021 18:34:46 +0200, > Ville Syrjälä wrote: > > > > On Fri, Apr 02, 2021 at 10:23:17AM +0200, Takashi Iwai wrote: > > > intel_dsm_platform_mux_info() tries to parse the ACPI package data > > > from _DSM for the debug in

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-07 Thread Takashi Iwai
On Wed, 07 Apr 2021 18:34:46 +0200, Ville Syrjälä wrote: > > On Fri, Apr 02, 2021 at 10:23:17AM +0200, Takashi Iwai wrote: > > intel_dsm_platform_mux_info() tries to parse the ACPI package data > > from _DSM for the debug information, but it assumes the fixed format > > without checking what value

Re: [Intel-gfx] [PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-07 Thread Ville Syrjälä
On Fri, Apr 02, 2021 at 10:23:17AM +0200, Takashi Iwai wrote: > intel_dsm_platform_mux_info() tries to parse the ACPI package data > from _DSM for the debug information, but it assumes the fixed format > without checking what values are stored in the elements actually. > When an unexpected value is

[PATCH v2] drm/i915: Fix invalid access to ACPI _DSM objects

2021-04-02 Thread Takashi Iwai
intel_dsm_platform_mux_info() tries to parse the ACPI package data from _DSM for the debug information, but it assumes the fixed format without checking what values are stored in the elements actually. When an unexpected value is returned from BIOS, it may lead to GPF or NULL dereference, as report