Vitaly Chikunov <vt@xxxxxxxxxxxx> writes: > Hi, > > There is new compilation error (for a second week for drm-tip[1] kernel): > > CC [M] drivers/hv/vmbus_drv.o > drivers/hv/vmbus_drv.c:2082:29: error: shift count >= width of type [-Werror,-Wshift-count-overflow] > static u64 vmbus_dma_mask = DMA_BIT_MASK(64); > ^~~~~~~~~~~~~~~~ > ./include/linux/dma-mapping.h:76:54: note: expanded from macro 'DMA_BIT_MASK' > #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) > ^ ~~~ > 1 error generated. > > I understand this looks like possible GCC (11.2.1) bug, but still it prevents > building kernel with CONFIG_HYPERV. It seems DMA_BIT_MASK(64) is very common: $ git grep DMA_BIT_MASK\(64\) | wc -l 230 Is Hyper-V vmbus_drv the only victim? What happens if you replace 'DMA_BIT_MASK(64)' with '~0ULL', does the rest of the drivers compile normally? -- Vitaly
