[tip:x86/urgent] x86/reboot: Use EFI reboot for Acer TravelMate X514-51T

[tip-bot for Jian-Hong Pan]

Commit-ID:  5767575c1211e8958e5dd80d6542998b519c8478
Gitweb:     https://git.kernel.org/tip/5767575c1211e8958e5dd80d6542998b519c8478
Author:     Jian-Hong Pan <jian-hong@xxxxxxxxxxxx>
AuthorDate: Fri, 12 Apr 2019 16:01:53 +0800
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 16 Apr 2019 09:49:16 +0200

x86/reboot: Use EFI reboot for Acer TravelMate X514-51T

Upon reboot, the Acer TravelMate X514-51T laptop appears to complete the
shutdown process, but then it hangs in BIOS POST with a black screen.

The problem is intermittent - at some points it has appeared related to
Secure Boot settings or different kernel builds, but ultimately we have
not been able to identify the exact conditions that trigger the issue to
come and go.

Besides, the EFI mode cannot be disabled in the BIOS of this model.

However, after extensive testing, we observe that using the EFI reboot
method reliably avoids the issue in all cases.

So add a boot time quirk to use EFI reboot on such systems.

Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=203119
Signed-off-by: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx>
Signed-off-by: Daniel Drake <drake@xxxxxxxxxxxx>
Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: linux@xxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20190412080152.3718-1-jian-hong@xxxxxxxxxxxx
[ Small clarification edits to the code and changelog. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/kernel/reboot.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 725624b6c0c0..8fd3cedd9acc 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -81,6 +81,19 @@ static int __init set_bios_reboot(const struct dmi_system_id *d)
 	return 0;
 }
 
+/*
+ * Some machines don't handle the default ACPI reboot method and
+ * require the EFI reboot method:
+ */
+static int __init set_efi_reboot(const struct dmi_system_id *d)
+{
+	if (reboot_type != BOOT_EFI && !efi_runtime_disabled()) {
+		reboot_type = BOOT_EFI;
+		pr_info("%s series board detected. Selecting EFI-method for reboot.\n", d->ident);
+	}
+	return 0;
+}
+
 void __noreturn machine_real_restart(unsigned int type)
 {
 	local_irq_disable();
@@ -166,6 +179,14 @@ static const struct dmi_system_id reboot_dmi_table[] __initconst = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
 		},
 	},
+	{	/* Handle reboot issue on Acer TravelMate X514-51T */
+		.callback = set_efi_reboot,
+		.ident = "Acer TravelMate X514-51T",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate X514-51T"),
+		},
+	},
 
 	/* Apple */
 	{	/* Handle problems with rebooting on Apple MacBook5 */