Re: [PATCH v11 13/13] powerpc/64s/radix: Enable huge vmalloc mappings

[Michael Ellerman <mpe@ellerman.id.au>]

Nicholas Piggin <npiggin@gmail.com> writes:
> Cc: linuxppc-dev@lists.ozlabs.org
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---

Acked-by: Michael Ellerman <mpe@ellerman.id.au>

cheers

>  .../admin-guide/kernel-parameters.txt         |  2 ++
>  arch/powerpc/Kconfig                          |  1 +
>  arch/powerpc/kernel/module.c                  | 21 +++++++++++++++----
>  3 files changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index a10b545c2070..d62df53e5200 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -3225,6 +3225,8 @@
>  
>  	nohugeiomap	[KNL,X86,PPC,ARM64] Disable kernel huge I/O mappings.
>  
> +	nohugevmalloc	[PPC] Disable kernel huge vmalloc mappings.
> +
>  	nosmt		[KNL,S390] Disable symmetric multithreading (SMT).
>  			Equivalent to smt=1.
>  
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 107bb4319e0e..781da6829ab7 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -181,6 +181,7 @@ config PPC
>  	select GENERIC_GETTIMEOFDAY
>  	select HAVE_ARCH_AUDITSYSCALL
>  	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
> +	select HAVE_ARCH_HUGE_VMALLOC		if HAVE_ARCH_HUGE_VMAP
>  	select HAVE_ARCH_JUMP_LABEL
>  	select HAVE_ARCH_KASAN			if PPC32 && PPC_PAGE_SHIFT <= 14
>  	select HAVE_ARCH_KASAN_VMALLOC		if PPC32 && PPC_PAGE_SHIFT <= 14
> diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
> index a211b0253cdb..07026335d24d 100644
> --- a/arch/powerpc/kernel/module.c
> +++ b/arch/powerpc/kernel/module.c
> @@ -87,13 +87,26 @@ int module_finalize(const Elf_Ehdr *hdr,
>  	return 0;
>  }
>  
> -#ifdef MODULES_VADDR
>  void *module_alloc(unsigned long size)
>  {
> +	unsigned long start = VMALLOC_START;
> +	unsigned long end = VMALLOC_END;
> +
> +#ifdef MODULES_VADDR
>  	BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
> +	start = MODULES_VADDR;
> +	end = MODULES_END;
> +#endif
> +
> +	/*
> +	 * Don't do huge page allocations for modules yet until more testing
> +	 * is done. STRICT_MODULE_RWX may require extra work to support this
> +	 * too.
> +	 */
>  
> -	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, GFP_KERNEL,
> -				    PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
> +	return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL,
> +				    PAGE_KERNEL_EXEC,
> +				    VM_NO_HUGE_VMAP | VM_FLUSH_RESET_PERMS,
> +				    NUMA_NO_NODE,
>  				    __builtin_return_address(0));
>  }
> -#endif
> -- 
> 2.23.0