diff mbox series

[V2] KVM: ARM: Remove pgtable page standard functions from stage-2 page tables

Message ID 1552397145-10665-1-git-send-email-anshuman.khandual@arm.com (mailing list archive)
State New, archived
Headers show
Series [V2] KVM: ARM: Remove pgtable page standard functions from stage-2 page tables | expand

Commit Message

Anshuman Khandual March 12, 2019, 1:25 p.m. UTC 
ARM64 standard pgtable functions are going to use pgtable_page_[ctor|dtor]
or pgtable_pmd_page_[ctor|dtor] constructs. At present KVM guest stage-2
PUD|PMD|PTE level page tabe pages are allocated with __get_free_page()
via mmu_memory_cache_alloc() but released with standard pud|pmd_free() or
pte_free_kernel(). These will fail once they start calling into pgtable_
[pmd]_page_dtor() for pages which never originally went through respective
constructor functions. Hence convert all stage-2 page table page release
functions to call buddy directly while freeing pages.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
Changes in V2:

- Updated stage2_pud_free() with NOP as per Suzuki
- s/__free_page/free_page/ in clear_stage2_pmd_entry() for uniformity

 arch/arm/include/asm/stage2_pgtable.h   | 4 ++--
 arch/arm64/include/asm/stage2_pgtable.h | 4 ++--
 virt/kvm/arm/mmu.c                      | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

Comments

Will Deacon April 1, 2019, 4:16 p.m. UTC | #1 
[+KVM/ARM folks, since I can't take this without an Ack in place from them]

My understanding is that this patch is intended to replace patch 3/4 in
this series:

http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html

On Tue, Mar 12, 2019 at 06:55:45PM +0530, Anshuman Khandual wrote:
> ARM64 standard pgtable functions are going to use pgtable_page_[ctor|dtor]
> or pgtable_pmd_page_[ctor|dtor] constructs. At present KVM guest stage-2
> PUD|PMD|PTE level page tabe pages are allocated with __get_free_page()
> via mmu_memory_cache_alloc() but released with standard pud|pmd_free() or
> pte_free_kernel(). These will fail once they start calling into pgtable_
> [pmd]_page_dtor() for pages which never originally went through respective
> constructor functions. Hence convert all stage-2 page table page release
> functions to call buddy directly while freeing pages.
> 
> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Acked-by: Yu Zhao <yuzhao@google.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
> Changes in V2:
> 
> - Updated stage2_pud_free() with NOP as per Suzuki
> - s/__free_page/free_page/ in clear_stage2_pmd_entry() for uniformity
> 
>  arch/arm/include/asm/stage2_pgtable.h   | 4 ++--
>  arch/arm64/include/asm/stage2_pgtable.h | 4 ++--
>  virt/kvm/arm/mmu.c                      | 2 +-
>  3 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h
> index de2089501b8b..fed02c3b4600 100644
> --- a/arch/arm/include/asm/stage2_pgtable.h
> +++ b/arch/arm/include/asm/stage2_pgtable.h
> @@ -32,14 +32,14 @@
>  #define stage2_pgd_present(kvm, pgd)		pgd_present(pgd)
>  #define stage2_pgd_populate(kvm, pgd, pud)	pgd_populate(NULL, pgd, pud)
>  #define stage2_pud_offset(kvm, pgd, address)	pud_offset(pgd, address)
> -#define stage2_pud_free(kvm, pud)		pud_free(NULL, pud)
> +#define stage2_pud_free(kvm, pud)		do { } while (0)
>  
>  #define stage2_pud_none(kvm, pud)		pud_none(pud)
>  #define stage2_pud_clear(kvm, pud)		pud_clear(pud)
>  #define stage2_pud_present(kvm, pud)		pud_present(pud)
>  #define stage2_pud_populate(kvm, pud, pmd)	pud_populate(NULL, pud, pmd)
>  #define stage2_pmd_offset(kvm, pud, address)	pmd_offset(pud, address)
> -#define stage2_pmd_free(kvm, pmd)		pmd_free(NULL, pmd)
> +#define stage2_pmd_free(kvm, pmd)		free_page((unsigned long)pmd)
>  
>  #define stage2_pud_huge(kvm, pud)		pud_huge(pud)
>  
> diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
> index 5412fa40825e..915809e4ac32 100644
> --- a/arch/arm64/include/asm/stage2_pgtable.h
> +++ b/arch/arm64/include/asm/stage2_pgtable.h
> @@ -119,7 +119,7 @@ static inline pud_t *stage2_pud_offset(struct kvm *kvm,
>  static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
>  {
>  	if (kvm_stage2_has_pud(kvm))
> -		pud_free(NULL, pud);
> +		free_page((unsigned long)pud);
>  }
>  
>  static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp)
> @@ -192,7 +192,7 @@ static inline pmd_t *stage2_pmd_offset(struct kvm *kvm,
>  static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd)
>  {
>  	if (kvm_stage2_has_pmd(kvm))
> -		pmd_free(NULL, pmd);
> +		free_page((unsigned long)pmd);
>  }
>  
>  static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud)
> diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
> index e9d28a7ca673..cbfbdadca8a5 100644
> --- a/virt/kvm/arm/mmu.c
> +++ b/virt/kvm/arm/mmu.c
> @@ -191,7 +191,7 @@ static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr
>  	VM_BUG_ON(pmd_thp_or_huge(*pmd));
>  	pmd_clear(pmd);
>  	kvm_tlb_flush_vmid_ipa(kvm, addr);
> -	pte_free_kernel(NULL, pte_table);
> +	free_page((unsigned long)pte_table);
>  	put_page(virt_to_page(pmd));
>  }
>  
> -- 
> 2.20.1
>
Yu Zhao April 1, 2019, 6:34 p.m. UTC | #2 
On Mon, Apr 01, 2019 at 05:16:38PM +0100, Will Deacon wrote:
> [+KVM/ARM folks, since I can't take this without an Ack in place from them]
> 
> My understanding is that this patch is intended to replace patch 3/4 in
> this series:
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html

Yes, and sorry for the confusion. I could send an updated series once
this patch is merged. Thanks.

> On Tue, Mar 12, 2019 at 06:55:45PM +0530, Anshuman Khandual wrote:
> > ARM64 standard pgtable functions are going to use pgtable_page_[ctor|dtor]
> > or pgtable_pmd_page_[ctor|dtor] constructs. At present KVM guest stage-2
> > PUD|PMD|PTE level page tabe pages are allocated with __get_free_page()
> > via mmu_memory_cache_alloc() but released with standard pud|pmd_free() or
> > pte_free_kernel(). These will fail once they start calling into pgtable_
> > [pmd]_page_dtor() for pages which never originally went through respective
> > constructor functions. Hence convert all stage-2 page table page release
> > functions to call buddy directly while freeing pages.
> > 
> > Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> > Acked-by: Yu Zhao <yuzhao@google.com>
> > Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> > ---
> > Changes in V2:
> > 
> > - Updated stage2_pud_free() with NOP as per Suzuki
> > - s/__free_page/free_page/ in clear_stage2_pmd_entry() for uniformity
> > 
> >  arch/arm/include/asm/stage2_pgtable.h   | 4 ++--
> >  arch/arm64/include/asm/stage2_pgtable.h | 4 ++--
> >  virt/kvm/arm/mmu.c                      | 2 +-
> >  3 files changed, 5 insertions(+), 5 deletions(-)
> > 
> > diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h
> > index de2089501b8b..fed02c3b4600 100644
> > --- a/arch/arm/include/asm/stage2_pgtable.h
> > +++ b/arch/arm/include/asm/stage2_pgtable.h
> > @@ -32,14 +32,14 @@
> >  #define stage2_pgd_present(kvm, pgd)		pgd_present(pgd)
> >  #define stage2_pgd_populate(kvm, pgd, pud)	pgd_populate(NULL, pgd, pud)
> >  #define stage2_pud_offset(kvm, pgd, address)	pud_offset(pgd, address)
> > -#define stage2_pud_free(kvm, pud)		pud_free(NULL, pud)
> > +#define stage2_pud_free(kvm, pud)		do { } while (0)
> >  
> >  #define stage2_pud_none(kvm, pud)		pud_none(pud)
> >  #define stage2_pud_clear(kvm, pud)		pud_clear(pud)
> >  #define stage2_pud_present(kvm, pud)		pud_present(pud)
> >  #define stage2_pud_populate(kvm, pud, pmd)	pud_populate(NULL, pud, pmd)
> >  #define stage2_pmd_offset(kvm, pud, address)	pmd_offset(pud, address)
> > -#define stage2_pmd_free(kvm, pmd)		pmd_free(NULL, pmd)
> > +#define stage2_pmd_free(kvm, pmd)		free_page((unsigned long)pmd)
> >  
> >  #define stage2_pud_huge(kvm, pud)		pud_huge(pud)
> >  
> > diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
> > index 5412fa40825e..915809e4ac32 100644
> > --- a/arch/arm64/include/asm/stage2_pgtable.h
> > +++ b/arch/arm64/include/asm/stage2_pgtable.h
> > @@ -119,7 +119,7 @@ static inline pud_t *stage2_pud_offset(struct kvm *kvm,
> >  static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
> >  {
> >  	if (kvm_stage2_has_pud(kvm))
> > -		pud_free(NULL, pud);
> > +		free_page((unsigned long)pud);
> >  }
> >  
> >  static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp)
> > @@ -192,7 +192,7 @@ static inline pmd_t *stage2_pmd_offset(struct kvm *kvm,
> >  static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd)
> >  {
> >  	if (kvm_stage2_has_pmd(kvm))
> > -		pmd_free(NULL, pmd);
> > +		free_page((unsigned long)pmd);
> >  }
> >  
> >  static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud)
> > diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
> > index e9d28a7ca673..cbfbdadca8a5 100644
> > --- a/virt/kvm/arm/mmu.c
> > +++ b/virt/kvm/arm/mmu.c
> > @@ -191,7 +191,7 @@ static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr
> >  	VM_BUG_ON(pmd_thp_or_huge(*pmd));
> >  	pmd_clear(pmd);
> >  	kvm_tlb_flush_vmid_ipa(kvm, addr);
> > -	pte_free_kernel(NULL, pte_table);
> > +	free_page((unsigned long)pte_table);
> >  	put_page(virt_to_page(pmd));
> >  }
> >  
> > -- 
> > 2.20.1
> >
Will Deacon April 2, 2019, 9:03 a.m. UTC | #3 
On Mon, Apr 01, 2019 at 12:34:25PM -0600, Yu Zhao wrote:
> On Mon, Apr 01, 2019 at 05:16:38PM +0100, Will Deacon wrote:
> > [+KVM/ARM folks, since I can't take this without an Ack in place from them]
> > 
> > My understanding is that this patch is intended to replace patch 3/4 in
> > this series:
> > 
> > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html
> 
> Yes, and sorry for the confusion. I could send an updated series once
> this patch is merged. Thanks.

That's alright, I think I'm on top of it (but I'll ask you to check whatever
I end up merging). Just wanted to make it easy for the kvm folks to dive in
with no context!

Will
Marc Zyngier April 8, 2019, 9:09 a.m. UTC | #4 
On 01/04/2019 17:16, Will Deacon wrote:
> [+KVM/ARM folks, since I can't take this without an Ack in place from them]
> 
> My understanding is that this patch is intended to replace patch 3/4 in
> this series:
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html
> 
> On Tue, Mar 12, 2019 at 06:55:45PM +0530, Anshuman Khandual wrote:
>> ARM64 standard pgtable functions are going to use pgtable_page_[ctor|dtor]
>> or pgtable_pmd_page_[ctor|dtor] constructs. At present KVM guest stage-2
>> PUD|PMD|PTE level page tabe pages are allocated with __get_free_page()
>> via mmu_memory_cache_alloc() but released with standard pud|pmd_free() or
>> pte_free_kernel(). These will fail once they start calling into pgtable_
>> [pmd]_page_dtor() for pages which never originally went through respective
>> constructor functions. Hence convert all stage-2 page table page release
>> functions to call buddy directly while freeing pages.
>>
>> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> Acked-by: Yu Zhao <yuzhao@google.com>
>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
>> ---
>> Changes in V2:
>>
>> - Updated stage2_pud_free() with NOP as per Suzuki
>> - s/__free_page/free_page/ in clear_stage2_pmd_entry() for uniformity
>>
>>  arch/arm/include/asm/stage2_pgtable.h   | 4 ++--
>>  arch/arm64/include/asm/stage2_pgtable.h | 4 ++--
>>  virt/kvm/arm/mmu.c                      | 2 +-
>>  3 files changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h
>> index de2089501b8b..fed02c3b4600 100644
>> --- a/arch/arm/include/asm/stage2_pgtable.h
>> +++ b/arch/arm/include/asm/stage2_pgtable.h
>> @@ -32,14 +32,14 @@
>>  #define stage2_pgd_present(kvm, pgd)		pgd_present(pgd)
>>  #define stage2_pgd_populate(kvm, pgd, pud)	pgd_populate(NULL, pgd, pud)
>>  #define stage2_pud_offset(kvm, pgd, address)	pud_offset(pgd, address)
>> -#define stage2_pud_free(kvm, pud)		pud_free(NULL, pud)
>> +#define stage2_pud_free(kvm, pud)		do { } while (0)
>>  
>>  #define stage2_pud_none(kvm, pud)		pud_none(pud)
>>  #define stage2_pud_clear(kvm, pud)		pud_clear(pud)
>>  #define stage2_pud_present(kvm, pud)		pud_present(pud)
>>  #define stage2_pud_populate(kvm, pud, pmd)	pud_populate(NULL, pud, pmd)
>>  #define stage2_pmd_offset(kvm, pud, address)	pmd_offset(pud, address)
>> -#define stage2_pmd_free(kvm, pmd)		pmd_free(NULL, pmd)
>> +#define stage2_pmd_free(kvm, pmd)		free_page((unsigned long)pmd)
>>  
>>  #define stage2_pud_huge(kvm, pud)		pud_huge(pud)
>>  
>> diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
>> index 5412fa40825e..915809e4ac32 100644
>> --- a/arch/arm64/include/asm/stage2_pgtable.h
>> +++ b/arch/arm64/include/asm/stage2_pgtable.h
>> @@ -119,7 +119,7 @@ static inline pud_t *stage2_pud_offset(struct kvm *kvm,
>>  static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
>>  {
>>  	if (kvm_stage2_has_pud(kvm))
>> -		pud_free(NULL, pud);
>> +		free_page((unsigned long)pud);
>>  }
>>  
>>  static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp)
>> @@ -192,7 +192,7 @@ static inline pmd_t *stage2_pmd_offset(struct kvm *kvm,
>>  static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd)
>>  {
>>  	if (kvm_stage2_has_pmd(kvm))
>> -		pmd_free(NULL, pmd);
>> +		free_page((unsigned long)pmd);
>>  }
>>  
>>  static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud)
>> diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
>> index e9d28a7ca673..cbfbdadca8a5 100644
>> --- a/virt/kvm/arm/mmu.c
>> +++ b/virt/kvm/arm/mmu.c
>> @@ -191,7 +191,7 @@ static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr
>>  	VM_BUG_ON(pmd_thp_or_huge(*pmd));
>>  	pmd_clear(pmd);
>>  	kvm_tlb_flush_vmid_ipa(kvm, addr);
>> -	pte_free_kernel(NULL, pte_table);
>> +	free_page((unsigned long)pte_table);
>>  	put_page(virt_to_page(pmd));
>>  }
>>  
>> -- 
>> 2.20.1
>>

Looks good to me, please take it via the arm64 tree with my

Acked-by: Marc Zyngier <marc.zyngier@arm.com>

Thanks,

	M.
Will Deacon April 8, 2019, 2:22 p.m. UTC | #5 
On Tue, Apr 02, 2019 at 10:04:30AM +0100, Will Deacon wrote:
> On Mon, Apr 01, 2019 at 12:34:25PM -0600, Yu Zhao wrote:
> > On Mon, Apr 01, 2019 at 05:16:38PM +0100, Will Deacon wrote:
> > > [+KVM/ARM folks, since I can't take this without an Ack in place from them]
> > > 
> > > My understanding is that this patch is intended to replace patch 3/4 in
> > > this series:
> > > 
> > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html
> > 
> > Yes, and sorry for the confusion. I could send an updated series once
> > this patch is merged. Thanks.
> 
> That's alright, I think I'm on top of it (but I'll ask you to check whatever
> I end up merging). Just wanted to make it easy for the kvm folks to dive in
> with no context!

Ok, I've pushed this out onto a temporary branch before I merge it into
-next:

https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=pgtable-ctors

Please can you confirm that it looks ok?

Thanks,

Will
Yu Zhao April 8, 2019, 5:18 p.m. UTC | #6 
On Mon, Apr 08, 2019 at 03:22:38PM +0100, Will Deacon wrote:
> On Tue, Apr 02, 2019 at 10:04:30AM +0100, Will Deacon wrote:
> > On Mon, Apr 01, 2019 at 12:34:25PM -0600, Yu Zhao wrote:
> > > On Mon, Apr 01, 2019 at 05:16:38PM +0100, Will Deacon wrote:
> > > > [+KVM/ARM folks, since I can't take this without an Ack in place from them]
> > > > 
> > > > My understanding is that this patch is intended to replace patch 3/4 in
> > > > this series:
> > > > 
> > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/638083.html
> > > 
> > > Yes, and sorry for the confusion. I could send an updated series once
> > > this patch is merged. Thanks.
> > 
> > That's alright, I think I'm on top of it (but I'll ask you to check whatever
> > I end up merging). Just wanted to make it easy for the kvm folks to dive in
> > with no context!
> 
> Ok, I've pushed this out onto a temporary branch before I merge it into
> -next:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=pgtable-ctors
> 
> Please can you confirm that it looks ok?

LGTM, thanks.
diff mbox series

Patch

diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h
index de2089501b8b..fed02c3b4600 100644
--- a/arch/arm/include/asm/stage2_pgtable.h
+++ b/arch/arm/include/asm/stage2_pgtable.h
@@ -32,14 +32,14 @@ 
 #define stage2_pgd_present(kvm, pgd)		pgd_present(pgd)
 #define stage2_pgd_populate(kvm, pgd, pud)	pgd_populate(NULL, pgd, pud)
 #define stage2_pud_offset(kvm, pgd, address)	pud_offset(pgd, address)
-#define stage2_pud_free(kvm, pud)		pud_free(NULL, pud)
+#define stage2_pud_free(kvm, pud)		do { } while (0)
 
 #define stage2_pud_none(kvm, pud)		pud_none(pud)
 #define stage2_pud_clear(kvm, pud)		pud_clear(pud)
 #define stage2_pud_present(kvm, pud)		pud_present(pud)
 #define stage2_pud_populate(kvm, pud, pmd)	pud_populate(NULL, pud, pmd)
 #define stage2_pmd_offset(kvm, pud, address)	pmd_offset(pud, address)
-#define stage2_pmd_free(kvm, pmd)		pmd_free(NULL, pmd)
+#define stage2_pmd_free(kvm, pmd)		free_page((unsigned long)pmd)
 
 #define stage2_pud_huge(kvm, pud)		pud_huge(pud)
 
diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
index 5412fa40825e..915809e4ac32 100644
--- a/arch/arm64/include/asm/stage2_pgtable.h
+++ b/arch/arm64/include/asm/stage2_pgtable.h
@@ -119,7 +119,7 @@  static inline pud_t *stage2_pud_offset(struct kvm *kvm,
 static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
 {
 	if (kvm_stage2_has_pud(kvm))
-		pud_free(NULL, pud);
+		free_page((unsigned long)pud);
 }
 
 static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp)
@@ -192,7 +192,7 @@  static inline pmd_t *stage2_pmd_offset(struct kvm *kvm,
 static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd)
 {
 	if (kvm_stage2_has_pmd(kvm))
-		pmd_free(NULL, pmd);
+		free_page((unsigned long)pmd);
 }
 
 static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud)
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index e9d28a7ca673..cbfbdadca8a5 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -191,7 +191,7 @@  static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr
 	VM_BUG_ON(pmd_thp_or_huge(*pmd));
 	pmd_clear(pmd);
 	kvm_tlb_flush_vmid_ipa(kvm, addr);
-	pte_free_kernel(NULL, pte_table);
+	free_page((unsigned long)pte_table);
 	put_page(virt_to_page(pmd));
 }