Re: [PATCH v8 0/3] x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory

Masayoshi Mizuma
2018-10-16T19:54:30Z

On Tue, Oct 16, 2018 at 09:11:14PM +0200, Borislav Petkov wrote:
> On Tue, Oct 16, 2018 at 11:13:54AM -0400, Masayoshi Mizuma wrote:
> > Hi Boris, Baoquan and all,
> >
> > I have created a RFC patch for adjust KASLR padding size.
> > This patch is based on Can's v8 patch [1/3], and the Can's patch
> > will be changed in the future, so this patch is just RFC.
> >
> > Welcome to any comments and suggestions. Thanks!
>
> ...
>
> > diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
> > index a06cbf019744..c987c725e93a 100644
> > --- a/arch/x86/include/uapi/asm/bootparam.h
> > +++ b/arch/x86/include/uapi/asm/bootparam.h
> > @@ -191,7 +191,8 @@ struct boot_params {
> > __u8 _pad7[0x290-0x1f1-sizeof(struct setup_header)];
> > __u32 edd_mbr_sig_buffer[EDD_MBR_SIG_MAX]; /* 0x290 */
> > struct boot_e820_entry e820_table[E820_MAX_ENTRIES_ZEROPAGE]; /* 0x2d0 */
> > - __u8 _pad8[48]; /* 0xcd0 */
> > + __u8 _pad8[40]; /* 0xcd0 */
> > + __u64 possible_mem_addr; /* 0xcf8 */
>
> Where in the example I gave you with add_e820ext() do you see members
> being added to struct boot_params?
>
> Take a look at it again pls.

Ah, sorry, I misunderstood your suggetion...
In parse_setup_data(), the data is picked up from boot_params,
so I thought it is also useful for this sitiation.
I'll try again, thanks!

- Masa