From bae995df93849afd7e275a208f07b7ddd4ab44e6 Mon Sep 17 00:00:00 2001 From: Stefan Lippers-Hollmann Date: Mon, 30 Mar 2015 22:44:27 +0200 Subject: [PATCH] x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirk commit 80313b3078fcd2ca51970880d90757f05879a193 upstream. The ASRock Q1900DC-ITX mainboard (Baytrail-D) hangs randomly in both BIOS and UEFI mode while rebooting unless reboot=pci is used. Add a quirk to reboot via the pci method. The problem is very intermittent and hard to debug, it might succeed rebooting just fine 40 times in a row - but fails half a dozen times the next day. It seems to be slightly less common in BIOS CSM mode than native UEFI (with the CSM disabled), but it does happen in either mode. Since I've started testing this patch in late january, rebooting has been 100% reliable. Most of the time it already hangs during POST, but occasionally it might even make it through the bootloader and the kernel might even start booting, but then hangs before the mode switch. The same symptoms occur with grub-efi, gummiboot and grub-pc, just as well as (at least) kernel 3.16-3.19 and 4.0-rc6 (I haven't tried older kernels than 3.16). Upgrading to the most current mainboard firmware of the ASRock Q1900DC-ITX, version 1.20, does not improve the situation. ( Searching the web seems to suggest that other Bay Trail-D mainboards might be affected as well. ) -- Signed-off-by: Stefan Lippers-Hollmann Cc: Matt Fleming Link: http://lkml.kernel.org/r/20150330224427.0fb58e42@mir Signed-off-by: Ingo Molnar [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- Reading git-format-patch failed