[trimmed cc list] On Wed, Jun 22, 2022 at 06:10:27AM +0800, kernel test robot wrote: > tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > branch HEAD: 34d1d36073ea4d4c532e8c8345627a9702be799e Add linux-next specific files for 20220621 > > Error/Warning reports: > > https://lore.kernel.org/linux-mm/202206212029.Yr5m7Cd3-lkp@xxxxxxxxx > https://lore.kernel.org/linux-mm/202206212033.3lgl72Fw-lkp@xxxxxxxxx SEP. (Networking) > https://lore.kernel.org/lkml/202206071511.FI7WLdZo-lkp@xxxxxxxxx The XFS warnings are in on this code: 1258 #ifdef CONFIG_FS_DAX 1259 int > 1260 xfs_dax_fault( 1261 struct vm_fault *vmf, 1262 enum page_entry_size pe_size, 1263 bool write_fault, 1264 pfn_t *pfn) 1265 { > 1266 return dax_iomap_fault(vmf, pe_size, pfn, NULL, 1267 (write_fault && !vmf->cow_page) ? 1268 &xfs_dax_write_iomap_ops : 1269 &xfs_read_iomap_ops); 1270 } 1271 #else 1272 int 1273 xfs_dax_fault( 1274 struct vm_fault *vmf, 1275 enum page_entry_size pe_size, 1276 bool write_fault, 1277 pfn_t *pfn) 1278 { 1279 return 0; 1280 } 1281 #endif As it's not declared static and the return type should be vm_fault_t. This code is not in the XFS tree, so I have to assume that it is in Andrew's tree and needs fixing there. But I don't think just changing 'int' to 'static vm_fault_t' is right. This CONFIG_FS_DAX wrapper just smells wrong. That is, the call to xfs_dax_fault() should be completely elided by the compiler if CONFIG_FS_DAX is not set because it is only called from inside a if (IS_DAX(inode)) {...} context. IS_DAX(inode) will always evaluate as zero when CONFIG_FS_DAX is not set, and so xfs_dax_fault() becomes unreacheable and gets elided. That's the way the current code in 5.19-rc3 works, and has for years. We can call dax_iomap_fault() directly as long as it is only in a (IS_DAX(inode) == true) conditional context. We do this all over the place with fs-dax code - we did quite a bit of work to set up the FSDAX code to avoid needing config conditional code in the filesystems like the above wrappers. I can't see anything that has changes this, so I'm at a loss to explain why this wrapper is needed in the current linux-next tree... I think these wrappers should go away (needing them would be a potentially serious regression!) and be reverted to the existing 5.19-rc3 code, not just be patched to make the prototypes correct. Ruan, Andrew, can you two work together to massage the changes that are pending in Andrew's tree to get them fixed? Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
