[PATCH v3] acpi: Fix ARM32 platforms compile issue introduced by fw_table changes

[Dan Williams]

Dave Jiang wrote:
> Linus reported that:
> After commit a103f46633fd the kernel stopped compiling for
> several ARM32 platforms that I am building with a bare metal
> compiler. Bare metal compilers (arm-none-eabi-) don't
> define __linux__.
> 
> This is because the header <acpi/platform/acenv.h> is now
> in the include path for <linux/irq.h>:
> 
>   CC      arch/arm/kernel/irq.o
>   CC      kernel/sysctl.o
>   CC      crypto/api.o
> In file included from ../include/acpi/acpi.h:22,
>                  from ../include/linux/fw_table.h:29,
>                  from ../include/linux/acpi.h:18,
>                  from ../include/linux/irqchip.h:14,
>                  from ../arch/arm/kernel/irq.c:25:
> ../include/acpi/platform/acenv.h:218:2: error: #error Unknown target environment
>   218 | #error Unknown target environment
>       |  ^~~~~
> 
> The issue is caused by the introducing of splitting out the ACPI code to
> support the new generic fw_table code.
> 
> Rafael suggested [1] moving the fw_table.h include in linux/acpi.h to below
> the linux/mutex.h. Remove the two includes in fw_table.h. Replace
> linux/fw_table.h include in fw_table.c with linux/acpi.h.
> 
> Link: https://lore.kernel.org/linux-acpi/CAJZ5v0idWdJq3JSqQWLG5q+b+b=zkEdWR55rGYEoxh7R6N8kFQ@mail.gmail.com/
> Fixes: a103f46633fd ("acpi: Move common tables helper functions to common lib")
> Closes: https://lore.kernel.org/linux-acpi/20231114-arm-build-bug-v1-1-458745fe32a4@linaro.org/
> Reported-by: Linus Walleij <linus.walleij at linaro.org>
> Suggested-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> Tested-by: Linus Walleij <linus.walleij at linaro.org>
> Signed-off-by: Dave Jiang <dave.jiang at intel.com>

Acked-by: Dan Williams <dan.j.williams at intel.com>

It concerns me that neither linux-next nor 0day robot exposure reported
this problem.

Does ARM32 require manual compilation coverage these days or was this
just a series of unfortunate events that the build bots missed this?