From: Arnd Bergmann <arnd@xxxxxxxx> In some randconfig builds, the IS_ERR() check appears to not get completely eliminated, resulting in the compiler to insert references to these two functions that cause a link failure: ERROR: modpost: "set_dax_nocache" [drivers/md/dm-mod.ko] undefined! ERROR: modpost: "set_dax_nomc" [drivers/md/dm-mod.ko] undefined! Add more stub functions for the dax-disabled case here to make it build again. Fixes: d888f6b0a766 ("dm: treat alloc_dax() -EOPNOTSUPP failure as non-fatal") Reported-by: kernel test robot <lkp@xxxxxxxxx> Closes: https://lore.kernel.org/oe-kbuild-all/202402160420.e4QKwoGO-lkp@xxxxxxxxx/ Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- include/linux/dax.h | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/include/linux/dax.h b/include/linux/dax.h index df2d52b8a245..4527c10016fb 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -64,6 +64,9 @@ void dax_write_cache(struct dax_device *dax_dev, bool wc); bool dax_write_cache_enabled(struct dax_device *dax_dev); bool dax_synchronous(struct dax_device *dax_dev); void set_dax_synchronous(struct dax_device *dax_dev); +void set_dax_nocache(struct dax_device *dax_dev); +void set_dax_nomc(struct dax_device *dax_dev); + size_t dax_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i); /* @@ -108,6 +111,12 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) static inline void set_dax_synchronous(struct dax_device *dax_dev) { } +static inline void set_dax_nocache(struct dax_device *dax_dev) +{ +} +static inline void set_dax_nomc(struct dax_device *dax_dev) +{ +} static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, struct dax_device *dax_dev) { @@ -120,9 +129,6 @@ static inline size_t dax_recovery_write(struct dax_device *dax_dev, } #endif -void set_dax_nocache(struct dax_device *dax_dev); -void set_dax_nomc(struct dax_device *dax_dev); - struct writeback_control; #if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX) int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk); -- 2.39.2