4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx> [ Upstream commit 32b53c012e0bfe20b2745962a89db0dc72ef3270 ] Memory hotplug is leading to hash page table calls, even on radix: arch_add_memory create_section_mapping htab_bolt_mapping BUG_ON(!ppc_md.hpte_insert); To fix, refactor {create,remove}_section_mapping() into hash__ and radix__ variants. Leave the radix versions stubbed for now. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx> Acked-by: Balbir Singh <bsingharora@xxxxxxxxx> Signed-off-by: Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/book3s/64/hash.h | 4 ++++ arch/powerpc/mm/hash_utils_64.c | 4 ++-- arch/powerpc/mm/pgtable-book3s64.c | 18 ++++++++++++++++++ 3 files changed, 24 insertions(+), 2 deletions(-) --- a/arch/powerpc/include/asm/book3s/64/hash.h +++ b/arch/powerpc/include/asm/book3s/64/hash.h @@ -201,6 +201,10 @@ extern int __meminit hash__vmemmap_creat unsigned long phys); extern void hash__vmemmap_remove_mapping(unsigned long start, unsigned long page_size); + +int hash__create_section_mapping(unsigned long start, unsigned long end); +int hash__remove_section_mapping(unsigned long start, unsigned long end); + #endif /* !__ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_BOOK3S_64_HASH_H */ --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -747,7 +747,7 @@ static unsigned long __init htab_get_tab } #ifdef CONFIG_MEMORY_HOTPLUG -int create_section_mapping(unsigned long start, unsigned long end) +int hash__create_section_mapping(unsigned long start, unsigned long end) { int rc = htab_bolt_mapping(start, end, __pa(start), pgprot_val(PAGE_KERNEL), mmu_linear_psize, @@ -761,7 +761,7 @@ int create_section_mapping(unsigned long return rc; } -int remove_section_mapping(unsigned long start, unsigned long end) +int hash__remove_section_mapping(unsigned long start, unsigned long end) { int rc = htab_remove_mapping(start, end, mmu_linear_psize, mmu_kernel_ssize); --- a/arch/powerpc/mm/pgtable-book3s64.c +++ b/arch/powerpc/mm/pgtable-book3s64.c @@ -125,3 +125,21 @@ void mmu_cleanup_all(void) else if (mmu_hash_ops.hpte_clear_all) mmu_hash_ops.hpte_clear_all(); } + +#ifdef CONFIG_MEMORY_HOTPLUG +int create_section_mapping(unsigned long start, unsigned long end) +{ + if (radix_enabled()) + return -ENODEV; + + return hash__create_section_mapping(start, end); +} + +int remove_section_mapping(unsigned long start, unsigned long end) +{ + if (radix_enabled()) + return -ENODEV; + + return hash__remove_section_mapping(start, end); +} +#endif /* CONFIG_MEMORY_HOTPLUG */