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. Could one ([5]) or the other ([6]) please be included in v6.6 (or earlier) to "fix" the build problem for ia64? Cheers, Frank [3]: https://github.com/torvalds/linux/commit/0a0e2ea642f6#diff-80c82874cec85e9c2facf52535b929ec62284c001ab081bfd1c1d164bf2a1d66R179 [4]: https://lore.kernel.org/lkml/c7a05a44-c0be-46c2-a21d-b242524d482b@xxxxxxxxxxxx/T/#u [5]: https://lore.kernel.org/lkml/CAJZ5v0hnNK4O_HyinvTp01YxXR7V4vzpMhf85yW9M2=52-O2Fg@xxxxxxxxxxxxxx/ [6]: https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/commit/?id=a0334bf78b95532cec54f56b53e8ae1bfe7e1ca1