Ard Biesheuvel f8585539df fbdev/efifb: Ignore framebuffer memmap entries that lack any memory types ... The following commit: 38ac0287b7 ("fbdev/efifb: Honour UEFI memory map attributes when mapping the FB") updated the EFI framebuffer code to use memory mappings for the linear framebuffer that are permitted by the memory attributes described by the EFI memory map for the particular region, if the framebuffer happens to be covered by the EFI memory map (which is typically only the case for framebuffers in shared memory). This is required since non-x86 systems may require cacheable attributes for memory mappings that are shared with other masters (such as GPUs), and this information cannot be described by the Graphics Output Protocol (GOP) EFI protocol itself, and so we rely on the EFI memory map for this. As reported by James, this breaks some x86 systems: [ 1.173368] efifb: probing for efifb [ 1.173386] efifb: abort, cannot remap video memory 0x1d5000 @ 0xcf800000 [ 1.173395] Trying to free nonexistent resource <00000000cf800000-00000000cf9d4bff> [ 1.173413] efi-framebuffer: probe of efi-framebuffer.0 failed with error -5 The problem turns out to be that the memory map entry that describes the framebuffer has no memory attributes listed at all, and so we end up with a mem_flags value of 0x0. So work around this by ensuring that the memory map entry's attribute field has a sane value before using it to mask the set of usable attributes. Reported-by: James Hilliard <james.hilliard1@gmail.com> Tested-by: James Hilliard <james.hilliard1@gmail.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: <stable@vger.kernel.org> # v4.19+ Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Fixes: 38ac0287b7 ("fbdev/efifb: Honour UEFI memory map attributes when ...") Link: http://lkml.kernel.org/r/20190516213159.3530-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>		2019-05-17 11:07:42 +02:00
..
backlight	lib/math: move int_pow() from pwm_bl.c for wider use	2019-05-14 19:52:49 -07:00
console	vgacon: unconfuse vc_origin when using soft scrollback	2019-01-18 13:45:22 +01:00
fbdev	fbdev/efifb: Ignore framebuffer memmap entries that lack any memory types	2019-05-17 11:07:42 +02:00
logo	fbdev: fbmem: convert CONFIG_FB_LOGO_CENTER into a cmd line option	2019-01-16 17:42:35 +01:00
display_timing.c
hdmi.c	drm-misc-next for v4.21, part 1:	2018-11-19 10:40:33 +10:00
Kconfig	fbdev changes for v4.17:	2018-04-10 10:20:00 -07:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
of_display_timing.c	fbdev: Convert to using %pOFn instead of device_node.name	2018-10-08 12:57:36 +02:00
of_videomode.c
vgastate.c	Video: vgastate: fixed a spacing coding style	2018-10-08 12:57:35 +02:00
videomode.c