After 'commit fc0c2028135c ("x86, pmem: use memcpy_mcsafe()
for memcpy_from_pmem()")', probing a PMEM device hits the BUG()
error below on X86_32 kernel.kernel BUG at include/linux/pmem.h:48! memcpy_from_pmem() calls arch_memcpy_from_pmem(), which is unimplemented since CONFIG_ARCH_HAS_PMEM_API is undefined on X86_32. Fix the BUG() error by adding default_memcpy_from_pmem(). Signed-off-by: Toshi Kani <[email protected]> Cc: Dan Williams <[email protected]> Cc: Ross Zwisler <[email protected]> --- include/linux/pmem.h | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/include/linux/pmem.h b/include/linux/pmem.h index ac6d872..57d146f 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -72,6 +72,18 @@ static inline void arch_invalidate_pmem(void __pmem *addr, size_t size) } #endif +static inline bool arch_has_pmem_api(void) +{ + return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API); +} + +static inline int default_memcpy_from_pmem(void *dst, void __pmem const *src, + size_t size) +{ + memcpy(dst, (void __force *) src, size); + return 0; +} + /* * memcpy_from_pmem - read from persistent memory with error handling * @dst: destination buffer @@ -83,12 +95,10 @@ static inline void arch_invalidate_pmem(void __pmem *addr, size_t size) static inline int memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) { - return arch_memcpy_from_pmem(dst, src, size); -} - -static inline bool arch_has_pmem_api(void) -{ - return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API); + if (arch_has_pmem_api()) + return arch_memcpy_from_pmem(dst, src, size); + else + return default_memcpy_from_pmem(dst, src, size); } /**
