Re: [PATCH v5 17/32] x86/mm: Add support to access boot related data in the clear

Tom Lendacky
2017-05-30T16:47:20Z

On 5/21/2017 2:16 AM, Borislav Petkov wrote:
> On Fri, May 19, 2017 at 03:50:32PM -0500, Tom Lendacky wrote:
>> The "worker" function would be doing the loop through the setup data,
>> but since the setup data is mapped inside the loop I can't do the __init
>> calling the non-init function and still hope to consolidate the code.
>> Maybe I'm missing something here...
>
> Hmm, I see what you mean. But the below change ontop doesn't fire any
> warnings here. Maybe your .config has something set which I don't...

Check if you have CONFIG_DEBUG_SECTION_MISMATCH=y

Thanks,
Tom

>
> ---
> diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> index 55317ba3b6dc..199c983192ae 100644
> --- a/arch/x86/mm/ioremap.c
> +++ b/arch/x86/mm/ioremap.c
> @@ -515,71 +515,50 @@ static bool memremap_is_efi_data(resource_size_t phys_addr,
> * Examine the physical address to determine if it is boot data by checking
> * it against the boot params setup_data chain.
> */
> -static bool memremap_is_setup_data(resource_size_t phys_addr,
> - unsigned long size)
> +static bool
> +__memremap_is_setup_data(resource_size_t phys_addr, unsigned long size, bool early)
> {
> struct setup_data *data;
> u64 paddr, paddr_next;
> + u32 len;
>
> paddr = boot_params.hdr.setup_data;
> while (paddr) {
> - bool is_setup_data = false;
>
> if (phys_addr == paddr)
> return true;
>
> - data = memremap(paddr, sizeof(*data),
> - MEMREMAP_WB | MEMREMAP_DEC);
> + if (early)
> + data = early_memremap_decrypted(paddr, sizeof(*data));
> + else
> + data = memremap(paddr, sizeof(*data), MEMREMAP_WB | MEMREMAP_DEC);
>
> paddr_next = data->next;
> + len = data->len;
>
> - if ((phys_addr > paddr) && (phys_addr < (paddr + data->len)))
> - is_setup_data = true;
> + if (early)
> + early_memunmap(data, sizeof(*data));
> + else
> + memunmap(data);
>
> - memunmap(data);
>
> - if (is_setup_data)
> + if ((phys_addr > paddr) && (phys_addr < (paddr + data->len)))
> return true;
>
> paddr = paddr_next;
> }
> -
> return false;
> }
>
> -/*
> - * Examine the physical address to determine if it is boot data by checking
> - * it against the boot params setup_data chain (early boot version).
> - */
> static bool __init early_memremap_is_setup_data(resource_size_t phys_addr,
> unsigned long size)
> {
> - struct setup_data *data;
> - u64 paddr, paddr_next;
> -
> - paddr = boot_params.hdr.setup_data;
> - while (paddr) {
> - bool is_setup_data = false;
> -
> - if (phys_addr == paddr)
> - return true;
> -
> - data = early_memremap_decrypted(paddr, sizeof(*data));
> -
> - paddr_next = data->next;
> -
> - if ((phys_addr > paddr) && (phys_addr < (paddr + data->len)))
> - is_setup_data = true;
> -
> - early_memunmap(data, sizeof(*data));
> -
> - if (is_setup_data)
> - return true;
> -
> - paddr = paddr_next;
> - }
> + return __memremap_is_setup_data(phys_addr, size, true);
> +}
>
> - return false;
> +static bool memremap_is_setup_data(resource_size_t phys_addr, unsigned long size)
> +{
> + return __memremap_is_setup_data(phys_addr, size, false);
> }
>
> /*
>