Dear all,
since v6.6-rc1 (actually introduced with [1], specific commit on [2])
the kernel build for ia64 fails like that:
```
Making kernel...
time make -j24
LOCALVERSION="-0bb80ecc33a8fb5a682236443c1e740d5c917d1d-ia64" ARCH=ia64 CROSS_COMPILE=ia64-linux- all
Mon Sep 11 06:24:43 PM CEST 2023
[...]
LD [M] net/sunrpc/sunrpc.ko
ia64-linux-ld: drivers/acpi/acpi_processor.o: in function `acpi_early_processor_osc': /usr/src/linux-on-ramdisk/torvalds-linux/drivers/acpi/acpi_processor.c:596: undefined reference to `acpi_proc_quirk_mwait_check'
ia64-linux-ld: drivers/acpi/processor_pdc.o: in function `acpi_early_processor_set_pdc': /usr/src/linux-on-ramdisk/torvalds-linux/drivers/acpi/processor_pdc.c:113: undefined reference to `acpi_proc_quirk_mwait_check'
make[2]: *** [scripts/Makefile.vmlinux:36: vmlinux] Error 1
make[1]: *** [/usr/src/linux-on-ramdisk/torvalds-linux/Makefile:1165:
vmlinux] Error 2
make: *** [Makefile:234: __sub-make] Error 2
real 3m25.286s
user 69m26.895s
sys 6m37.619s
2
```
[1]:
https://github.com/torvalds/linux/commit/9bd0c413b90c6517b4a2fbedb74f50df3421b50c
[2]:
https://github.com/torvalds/linux/commit/0a0e2ea642f6
In short, the change introduced a function call ([3]) in effect for ia64 without providing an implementation for that function for ia64. There's
a discussion thread on [4] that also includes a patch ([5]) to "fix" the problem but that one unfortunately wasn't included in [1] or [2]:
```
---
drivers/acpi/internal.h | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)
Index: linux-pm/drivers/acpi/internal.h ===================================================================
--- linux-pm.orig/drivers/acpi/internal.h
+++ linux-pm/drivers/acpi/internal.h
@@ -148,8 +148,11 @@ int acpi_wakeup_device_init(void);
#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
void acpi_early_processor_control_setup(void);
void acpi_early_processor_set_pdc(void);
-
+#ifdef CONFIG_X86
void acpi_proc_quirk_mwait_check(void);
+#else
+static inline void acpi_proc_quirk_mwait_check(void) {}
+#endif
bool processor_physically_present(acpi_handle handle);
#else
static inline void acpi_early_processor_control_setup(void) {}
```
For me this patch solves the build problem for v6.6-rc1 and -rc2.
There's also another patch available for that specific problem by Ard
([6]) but I haven't seen this one included either up until 42dc814 and I
also haven't tested this one.
Coul