ACPI / bus: Only call dmi_check_system on X86
PATCH v2 1/1 ACPI / bus: Only call dmi_check_system on X86
Calling dmi_check_system() early only works on X86. Other architectures initialize the DMI subsystem later so it's not ready yet when ACPI itself gets initialized.
In the best case it results in a useless call to a function which will do nothing. But depending on the dmi implementation, it could also result in warnings. Best is to not call the function when it can't work and isn't needed.
Additionally, if anyone ever needs to add non-x86 quirks, it would surprisingly not work, so document the limitation to avoid confusion.
Signed-off-by Jean Delvare <[email protected]>
Fixes cce4f632db20 ("ACPI: fix early DSDT dmi check warnings on ia64")
Cc Takashi Iwai <[email protected]>
Cc "Rafael J. Wysocki" <[email protected]>
Cc Len Brown <[email protected]>
---
Changes since v1:
* Rebased on top of v4.19-rc2 to avoid conflicts with recent ACPI changes.
* Fix typo in comment.
drivers/acpi/bus.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
drivers/acpi/bus.c +7 -6
@@ -35,11 +35,11 @@#include <linux/delay.h> #ifdef CONFIG_X86 #include <asm/mpspec.h> +#include <linux/dmi.h> #endif #include <linux/acpi_iort.h> #include <linux/pci.h> #include <acpi/apei.h> -#include <linux/dmi.h> #include <linux/suspend.h> #include "internal.h"
@@ -82,10 +82,6 @@ static const struct dmi_system_id dsdt_d }, {} }; -#else -static const struct dmi_system_id dsdt_dmi_table[]__initconst = { - {} -};#endif /* --------------------------------------------------------------------------
@@ -1033,11 +1029,16 @@ void __init acpi_early_init(void) acpi_permanent_mmap = true; +#ifdef CONFIG_X86 /* * If the machine falls into the DMI check table, -* DSDT will be copied to memory +* DSDT will be copied to memory. +* Note that calling dmi_check_system here on other architectures +* would not be OK because only x86 initializes dmi early enough. +* Thankfully only x86 systems need such quirks for now. */ dmi_check_system (dsdt_dmi_table); +#endif status =acpi_reallocate_root_table ();if (ACPI_FAILURE (status)) {
Signature · 2 lines
Jean Delvare SUSE L3 Support