| Message ID | 3821285.7cLYDZsCsX@wuerfel (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 23/09/15 10:39, Arnd Bergmann wrote: > On Wednesday 23 September 2015 10:15:42 Sudeep Holla wrote: >> On 15/09/15 09:34, Viresh Kumar wrote: >>> global_lock is defined as an unsigned long and accessing only its lower >>> 32 bits from sysfs is incorrect, as we need to consider other 32 bits >>> for big endian 64 bit systems. >>> >>> Fix that by making global_lock an u32 instead. >>> >>> Cc: <stable@vger.kernel.org> # v4.1+ >>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> >>> >>> --- >>> Its marked just for # v4.1+, because arm64 has the first 64 big-endian >>> platform with ACPI. And ACPI support for that is mainlined recently >>> only (Arnd Bergmann). >>> >> >> Just to clarify, we don't support big-endian with ACPI on ARM64. >> We mandate use of EFI for ACPI on ARM64 and EFI spec mandates only >> little endian. >> > > EFI doesn't care what endianess the kernel has, as long as the > data structures are interpreted in the same way that the firmware > defines them, and I thought that at least UEFI on ARM64 with big-endian > is working in principle (if not, that is a bug that should be fixed). > > If ACPI is broken with big-endian kernels, we should probably add a > Kconfig statement to forbid it, like this: > The diff looks sensible thing to have to avoid enabling ACPI with BE though I am not sure if this can be regarded as broken as it could be case of just not supported(my guess as I am not completely aware of the history). Also I am not against the $subject patch as such, just added clarification so that it shouldn't be assumed that BE + ACPI works on ARM64. Regards, Sudeep > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > index 5d1015c26ff4..06cacc13e3d2 100644 > --- a/drivers/acpi/Kconfig > +++ b/drivers/acpi/Kconfig > @@ -6,6 +6,7 @@ menuconfig ACPI > bool "ACPI (Advanced Configuration and Power Interface) Support" > depends on !IA64_HP_SIM > depends on IA64 || X86 || (ARM64 && EXPERT) > + depends on !ARM64 || !CPU_BIG_ENDIAN || BROKEN > depends on PCI > select PNP > default y > > > Arnd > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wednesday 23 September 2015 10:57:44 Sudeep Holla wrote: > > Also I am not against the $subject patch as such, just added > clarification so that it shouldn't be assumed that BE + ACPI works on > ARM64. > Ok, at least we can safely assume that we do not need to backport that patch to stable then. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 5d1015c26ff4..06cacc13e3d2 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -6,6 +6,7 @@ menuconfig ACPI bool "ACPI (Advanced Configuration and Power Interface) Support" depends on !IA64_HP_SIM depends on IA64 || X86 || (ARM64 && EXPERT) + depends on !ARM64 || !CPU_BIG_ENDIAN || BROKEN depends on PCI select PNP default y