Hi, On 12/22/23 9:02 PM, David Howells wrote: > This needs an additional change (see attached). > > diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig > index 1d318f85232d..1949763e66aa 100644 > --- a/fs/erofs/Kconfig > +++ b/fs/erofs/Kconfig > @@ -114,7 +114,8 @@ config EROFS_FS_ZIP_DEFLATE > > config EROFS_FS_ONDEMAND > bool "EROFS fscache-based on-demand read support" > - depends on CACHEFILES_ONDEMAND && (EROFS_FS=m && FSCACHE || EROFS_FS=y && FSCACHE=y) > + depends on CACHEFILES_ONDEMAND && FSCACHE && \ > + (EROFS_FS=m && NETFS_SUPPORT || EROFS_FS=y && NETFS_SUPPORT=y) > default n > help > This permits EROFS to use fscache-backed data blobs with on-demand > Thanks for the special reminder. I noticed that it has been included in this commit[*] in the dev tree. [*] https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?h=netfs-lib&id=7472173cc3baf4a0bd8c803e56c37efdb8388f1c Besides I noticed an issue when trying to configure EROFS_FS_ONDEMAND. The above kconfig indicates that EROFS_FS_ONDEMAND depends on NETFS_SUPPORT, while NETFS_SUPPORT has no prompt in menuconfig and can only be selected by, e.g. fs/ceph/Kconfig: config CEPH_FS select NETFS_SUPPORT IOW EROFS_FS_ONDEMAND will not be prompted and has no way being configured if NETFS_SUPPORT itself is not selected by any other filesystem. I tried to fix this in following way: diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig index 1949763e66aa..5b7b71e537f1 100644 --- a/fs/erofs/Kconfig +++ b/fs/erofs/Kconfig @@ -5,6 +5,7 @@ config EROFS_FS depends on BLOCK select FS_IOMAP select LIBCRC32C + select NETFS_SUPPORT if EROFS_FS_ONDEMAND help EROFS (Enhanced Read-Only File System) is a lightweight read-only file system with modern designs (e.g. no buffer heads, inline @@ -114,8 +115,10 @@ config EROFS_FS_ZIP_DEFLATE config EROFS_FS_ONDEMAND bool "EROFS fscache-based on-demand read support" - depends on CACHEFILES_ONDEMAND && FSCACHE && \ - (EROFS_FS=m && NETFS_SUPPORT || EROFS_FS=y && NETFS_SUPPORT=y) + depends on EROFS_FS + select FSCACHE default n help This permits EROFS to use fscache-backed data blobs with on-demand But still the dependency for CACHEFILES_ONDEMAND and CACHEFILES can not be resolved. Though CACHEFILES is not a must during the linking stage as EROFS only calls fscache APIs directly, CACHEFILES is indeed needed to ensure that the EROFS on-demand functionality works at runtime. If we let EROFS_FS_ONDEMAND select CACHEFILES_ONDEMAND, then only CACHEFILES_ONDEMAND will be selected while CACHEFILES can be still N. Maybe EROFS_FS_ONDEMAND needs to selct both CACHEFILES_ONDEMAND and CACHEFILES? Besides if we make EROFS_FS_ONDEMAND depends on CACHEFILES_ONDEMAND, then there will be a recursive dependency loop, as fs/netfs/Kconfig:3:error: recursive dependency detected! fs/netfs/Kconfig:3: symbol NETFS_SUPPORT is selected by EROFS_FS_ONDEMAND fs/erofs/Kconfig:116: symbol EROFS_FS_ONDEMAND depends on CACHEFILES_ONDEMAND fs/cachefiles/Kconfig:30: symbol CACHEFILES_ONDEMAND depends on CACHEFILES fs/cachefiles/Kconfig:3: symbol CACHEFILES depends on NETFS_SUPPORT Hi Xiang, any better idea? -- Thanks, Jingbo