From f6c46b1d62f8ffbf2cf6eb43ab0d277bd3f7e948 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Fri, 11 Mar 2022 19:20:17 +0000 Subject: PM: hibernate: Honour ACPI hardware signature by default for virtual guests The ACPI specification says that OSPM should refuse to restore from hibernate if the hardware signature changes, and should boot from scratch. However, real BIOSes often vary the hardware signature in cases where we *do* want to resume from hibernate, so Linux doesn't follow the spec by default. However, in a virtual environment there's no reason for the VMM to vary the hardware signature *unless* it wants to trigger a clean reboot as defined by the ACPI spec. So enable the check by default if a hypervisor is detected. Signed-off-by: David Woodhouse Signed-off-by: Rafael J. Wysocki --- include/linux/acpi.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 6274758648e3..766dbcb82df1 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -526,7 +526,7 @@ acpi_status acpi_release_memory(acpi_handle handle, struct resource *res, int acpi_resources_are_enforced(void); #ifdef CONFIG_HIBERNATION -void __init acpi_check_s4_hw_signature(int check); +extern int acpi_check_s4_hw_signature; #endif #ifdef CONFIG_PM_SLEEP -- cgit v1.2.3-71-gd317