以下の nvidia のドライバが Linux 5.3 でコンパイルできない話．
- nvidia-kernel-dkms 418.74-1
- nvidia-legacy-390xx-kernel-dkms 390.116-1
具体的には以下のエラー．
In file included from /var/lib/dkms/nvidia-current/418.74/build/nvidia/nv_uvm_interface.c:21:
/var/lib/dkms/nvidia-current/418.74/build/nvidia/nv_uvm_interface.c: In function ‘nvUvmInterfaceDeRegisterUvmOps’:
/var/lib/dkms/nvidia-current/418.74/build/common/inc/nv-linux.h:733:21: error: void value not ignored as it ought to be
int __ret = on_each_cpu(func, info, 1); \
^~~~~~~~~~~
/var/lib/dkms/nvidia-current/418.74/build/nvidia/nv_uvm_interface.c:991:5: note: in expansion of macro ‘NV_ON_EACH_CPU’
NV_ON_EACH_CPU(flush_top_half, NULL);
^~~~~~~~~~~~~~これは smp: Remove smp_call_function() and on_each_cpu() return values で on_each_cpu が値を返さなくなったということなので，マクロでダミーの正常時の戻り値を作ってしまえばOK．以下パッチ．nvidia-legacy-390xx-kernel-dkms も同様．
--- a/common/inc/nv-linux.h
+++ b/common/inc/nv-linux.h
@@ -730,8 +730,8 @@ static inline void nv_vunmap(NvUPtr vaddr, NvU32 page_count)
#elif (NV_ON_EACH_CPU_ARGUMENT_COUNT == 3)
#define NV_ON_EACH_CPU(func, info) \
({ \
- int __ret = on_each_cpu(func, info, 1); \
- __ret; \
+ on_each_cpu(func, info, 1); \
+ 0; \
})
#else
#error "NV_ON_EACH_CPU_ARGUMENT_COUNT value unrecognized!"