Re: [PATCH][kvm-unit-tests] nEPT: Fix test cases for 2M huge pages

[Paolo Bonzini <pbonzini@redhat.com>]

Il 23/10/2013 15:38, Jan Kiszka ha scritto:
> If 2M pages are available with EPT, the test code creates its initial
> identity map with such pages. But then it tries to remap two 4K pages in
> that range which fails as their level 3 PTE is set up for huge pages.
> 
> Fix this up by ensuring that install_ept_entry always create non-large
> page directory entries and by remapping the 2M area around those two
> test pages in 4K chunks.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  x86/vmx.c       | 3 ++-
>  x86/vmx.h       | 3 ++-
>  x86/vmx_tests.c | 8 ++++++++
>  3 files changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/x86/vmx.c b/x86/vmx.c
> index 9db4ef4..3e6fc37 100644
> --- a/x86/vmx.c
> +++ b/x86/vmx.c
> @@ -173,7 +173,8 @@ void install_ept_entry(unsigned long *pml4,
>  			memset(new_pt, 0, PAGE_SIZE);
>  			pt[offset] = virt_to_phys(new_pt)
>  					| EPT_RA | EPT_WA | EPT_EA;
> -		}
> +		} else
> +			pt[offset] &= ~EPT_LARGE_PAGE;
>  		pt = phys_to_virt(pt[offset] & 0xffffffffff000ull);
>  	}
>  	offset = ((unsigned long)guest_addr >> ((level-1) *
> diff --git a/x86/vmx.h b/x86/vmx.h
> index dc1ebdf..7d967eb 100644
> --- a/x86/vmx.h
> +++ b/x86/vmx.h
> @@ -485,7 +485,8 @@ enum Ctrl1 {
>  #define	EPT_PAGE_LEVEL	4
>  #define	EPT_PGDIR_WIDTH	9
>  #define	EPT_PGDIR_MASK	511
> -#define PAGE_MASK (~(PAGE_SIZE-1))
> +#define PAGE_MASK		(~(PAGE_SIZE-1))
> +#define PAGE_MASK_2M		(~(PAGE_SIZE_2M-1))
>  
>  #define EPT_VLT_RD		1
>  #define EPT_VLT_WR		(1 << 1)
> diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
> index 0759e10..a002a7a 100644
> --- a/x86/vmx_tests.c
> +++ b/x86/vmx_tests.c
> @@ -915,6 +915,7 @@ static int setup_ept()
>  
>  static void ept_init()
>  {
> +	unsigned long base_addr1, base_addr2;
>  	u32 ctrl_cpu[2];
>  
>  	init_fail = false;
> @@ -934,6 +935,13 @@ static void ept_init()
>  	memset(data_page2, 0x0, PAGE_SIZE);
>  	*((u32 *)data_page1) = MAGIC_VAL_1;
>  	*((u32 *)data_page2) = MAGIC_VAL_2;
> +	base_addr1 = (unsigned long)data_page1 & PAGE_MASK_2M;
> +	base_addr2 = (unsigned long)data_page2 & PAGE_MASK_2M;
> +	if (setup_ept_range(pml4, base_addr1, base_addr1 + PAGE_SIZE_2M, 0, 0,
> +			    EPT_WA | EPT_RA | EPT_EA) ||
> +	    setup_ept_range(pml4, base_addr2, base_addr2 + PAGE_SIZE_2M, 0, 0,
> +			    EPT_WA | EPT_RA | EPT_EA))
> +		init_fail = true;
>  	install_ept(pml4, (unsigned long)data_page1, (unsigned long)data_page2,
>  			EPT_RA | EPT_WA | EPT_EA);
>  }
> 

Applied to kvm-unit-tests.git vmx.

Paolo