On 9/10/18 6:36 AM, Borislav Petkov wrote:
> On Fri, Sep 07, 2018 at 12:57:27PM -0500, Brijesh Singh wrote:
>> Fix sme_populate_pgd() to update page flags if the PMD/PTE entry
>> already exists.
>>
>> Signed-off-by: Brijesh Singh <[email protected]>
>> Reviewed-by: Tom Lendacky <[email protected]>
>> Cc: Tom Lendacky <[email protected]>
>> Cc: [email protected]
>> Cc: Thomas Gleixner <[email protected]>
>> Cc: Borislav Petkov <[email protected]>
>> Cc: "H. Peter Anvin" <[email protected]>
>> Cc: [email protected]
>> Cc: Paolo Bonzini <[email protected]>
>> Cc: Sean Christopherson <[email protected]>
>> Cc: [email protected]
>> Cc: "Radim Krčmář" <[email protected]>
>> ---
>> arch/x86/mm/mem_encrypt_identity.c | 6 +-----
>> 1 file changed, 1 insertion(+), 5 deletions(-)
>>
>> diff --git a/arch/x86/mm/mem_encrypt_identity.c
>> b/arch/x86/mm/mem_encrypt_identity.c
>> index 92265d3..7659e65 100644
>> --- a/arch/x86/mm/mem_encrypt_identity.c
>> +++ b/arch/x86/mm/mem_encrypt_identity.c
>> @@ -154,9 +154,6 @@ static void __init sme_populate_pgd_large(struct
>> sme_populate_pgd_data *ppd)
>> return;
>>
>> pmd = pmd_offset(pud, ppd->vaddr);
>> - if (pmd_large(*pmd))
>> - return;
>> -
>> set_pmd(pmd, __pmd(ppd->paddr | ppd->pmd_flags));
>> }
>>
>> @@ -182,8 +179,7 @@ static void __init sme_populate_pgd(struct
>> sme_populate_pgd_data *ppd)
>> return;
>>
>> pte = pte_offset_map(pmd, ppd->vaddr);
>> - if (pte_none(*pte))
>> - set_pte(pte, __pte(ppd->paddr | ppd->pte_flags));
>> + set_pte(pte, __pte(ppd->paddr | ppd->pte_flags));
>> }
>>
>> static void __init __sme_map_range_pmd(struct sme_populate_pgd_data *ppd)
>> --
> This looks like a bugfix to me and as such should be:
>
> * at the beginning of the series
> * contain a Fixes: tag
> * contain Cc: <[email protected]>
>
> Right?
Based on your advice I was going to submit this series to stable
separately. This particular issue is not affecting anyone right now. The
only user to this function is sme_kernel_encrypt() which never updates
the PTE/PMD entries. I can update the commit message like this this to
clarify it.
Enhance the sme_populate_pgd() to update page flags if the PMD/PTE entry
already exists.
> With that addressed:
>
> Reviewed-by: Borislav Petkov <[email protected]>
>
