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[PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()

Mark Brown posted 3 patches 1 year, 3 months ago
There is a newer version of this series
[PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()
Posted by Mark Brown 1 year, 3 months ago 
In preparation for using vm_flags to ensure guard pages for shadow stacks
supply them as an argument to generic_get_unmapped_area(). The only user
outside of the core code is the PowerPC book3s64 implementation which is
trivially wrapping the generic implementation in the radix_enabled() case.

Signed-off-by: Mark Brown <broonie@kernel.org>
---
 arch/powerpc/mm/book3s64/slice.c |  4 ++--
 include/linux/sched/mm.h         |  4 ++--
 mm/mmap.c                        | 10 ++++++----
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c
index ada6bf896ef8..87307d0fc3b8 100644
--- a/arch/powerpc/mm/book3s64/slice.c
+++ b/arch/powerpc/mm/book3s64/slice.c
@@ -641,7 +641,7 @@ unsigned long arch_get_unmapped_area(struct file *filp,
 				     vm_flags_t vm_flags)
 {
 	if (radix_enabled())
-		return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
+		return generic_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags);
 
 	return slice_get_unmapped_area(addr, len, flags,
 				       mm_ctx_user_psize(&current->mm->context), 0);
@@ -655,7 +655,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
 					     vm_flags_t vm_flags)
 {
 	if (radix_enabled())
-		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags);
+		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags, vm_flags);
 
 	return slice_get_unmapped_area(addr0, len, flags,
 				       mm_ctx_user_psize(&current->mm->context), 1);
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index c4d34abc45d4..07bb8d4181d7 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -204,11 +204,11 @@ unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm,
 unsigned long
 generic_get_unmapped_area(struct file *filp, unsigned long addr,
 			  unsigned long len, unsigned long pgoff,
-			  unsigned long flags);
+			  unsigned long flags, vm_flags_t vm_flags);
 unsigned long
 generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 				  unsigned long len, unsigned long pgoff,
-				  unsigned long flags);
+				  unsigned long flags, vm_flags_t vm_flags);
 #else
 static inline void arch_pick_mmap_layout(struct mm_struct *mm,
 					 struct rlimit *rlim_stack) {}
diff --git a/mm/mmap.c b/mm/mmap.c
index 7528146f886f..b06ba847c96e 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1789,7 +1789,7 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info)
 unsigned long
 generic_get_unmapped_area(struct file *filp, unsigned long addr,
 			  unsigned long len, unsigned long pgoff,
-			  unsigned long flags)
+			  unsigned long flags, vm_flags_t vm_flags)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma, *prev;
@@ -1823,7 +1823,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 		       unsigned long len, unsigned long pgoff,
 		       unsigned long flags, vm_flags_t vm_flags)
 {
-	return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
+	return generic_get_unmapped_area(filp, addr, len, pgoff, flags,
+					 vm_flags);
 }
 #endif
 
@@ -1834,7 +1835,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 unsigned long
 generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 				  unsigned long len, unsigned long pgoff,
-				  unsigned long flags)
+				  unsigned long flags, vm_flags_t vm_flags)
 {
 	struct vm_area_struct *vma, *prev;
 	struct mm_struct *mm = current->mm;
@@ -1887,7 +1888,8 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 			       unsigned long len, unsigned long pgoff,
 			       unsigned long flags, vm_flags_t vm_flags)
 {
-	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
+	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags,
+						 vm_flags);
 }
 #endif
 

-- 
2.39.2
Re: [PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()
Posted by Deepak Gupta 1 year, 3 months ago 
On Mon, Sep 02, 2024 at 08:08:14PM +0100, Mark Brown wrote:
>In preparation for using vm_flags to ensure guard pages for shadow stacks
>supply them as an argument to generic_get_unmapped_area(). The only user
>outside of the core code is the PowerPC book3s64 implementation which is
>trivially wrapping the generic implementation in the radix_enabled() case.
>
>Signed-off-by: Mark Brown <broonie@kernel.org>

Reviewed-by: Deepak Gupta <debug@rivosinc.com>
Re: [PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()
Posted by Michael Ellerman 1 year, 3 months ago 
Mark Brown <broonie@kernel.org> writes:
> In preparation for using vm_flags to ensure guard pages for shadow stacks
> supply them as an argument to generic_get_unmapped_area(). The only user
> outside of the core code is the PowerPC book3s64 implementation which is
> trivially wrapping the generic implementation in the radix_enabled() case.
>
> Signed-off-by: Mark Brown <broonie@kernel.org>
> ---
>  arch/powerpc/mm/book3s64/slice.c |  4 ++--
>  include/linux/sched/mm.h         |  4 ++--
>  mm/mmap.c                        | 10 ++++++----
>  3 files changed, 10 insertions(+), 8 deletions(-)

Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

cheers

> diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c
> index ada6bf896ef8..87307d0fc3b8 100644
> --- a/arch/powerpc/mm/book3s64/slice.c
> +++ b/arch/powerpc/mm/book3s64/slice.c
> @@ -641,7 +641,7 @@ unsigned long arch_get_unmapped_area(struct file *filp,
>  				     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +		return generic_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags);
>  
>  	return slice_get_unmapped_area(addr, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 0);
> @@ -655,7 +655,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
>  					     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags);
> +		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags, vm_flags);
>  
>  	return slice_get_unmapped_area(addr0, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 1);
> diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
> index c4d34abc45d4..07bb8d4181d7 100644
> --- a/include/linux/sched/mm.h
> +++ b/include/linux/sched/mm.h
> @@ -204,11 +204,11 @@ unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm,
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags);
> +			  unsigned long flags, vm_flags_t vm_flags);
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags);
> +				  unsigned long flags, vm_flags_t vm_flags);
>  #else
>  static inline void arch_pick_mmap_layout(struct mm_struct *mm,
>  					 struct rlimit *rlim_stack) {}
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7528146f886f..b06ba847c96e 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1789,7 +1789,7 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info)
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags)
> +			  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct mm_struct *mm = current->mm;
>  	struct vm_area_struct *vma, *prev;
> @@ -1823,7 +1823,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  		       unsigned long len, unsigned long pgoff,
>  		       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area(filp, addr, len, pgoff, flags,
> +					 vm_flags);
>  }
>  #endif
>  
> @@ -1834,7 +1835,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags)
> +				  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct vm_area_struct *vma, *prev;
>  	struct mm_struct *mm = current->mm;
> @@ -1887,7 +1888,8 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  			       unsigned long len, unsigned long pgoff,
>  			       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags,
> +						 vm_flags);
>  }
>  #endif
>  
>
> -- 
> 2.39.2
Re: [PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()
Posted by Liam R. Howlett 1 year, 3 months ago 
* Mark Brown <broonie@kernel.org> [240902 15:09]:
> In preparation for using vm_flags to ensure guard pages for shadow stacks
> supply them as an argument to generic_get_unmapped_area(). The only user
> outside of the core code is the PowerPC book3s64 implementation which is
> trivially wrapping the generic implementation in the radix_enabled() case.
> 
> Signed-off-by: Mark Brown <broonie@kernel.org>


It is interesting that book3s64 ppc is special in this regard.

Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

> ---
>  arch/powerpc/mm/book3s64/slice.c |  4 ++--
>  include/linux/sched/mm.h         |  4 ++--
>  mm/mmap.c                        | 10 ++++++----
>  3 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c
> index ada6bf896ef8..87307d0fc3b8 100644
> --- a/arch/powerpc/mm/book3s64/slice.c
> +++ b/arch/powerpc/mm/book3s64/slice.c
> @@ -641,7 +641,7 @@ unsigned long arch_get_unmapped_area(struct file *filp,
>  				     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +		return generic_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags);
>  
>  	return slice_get_unmapped_area(addr, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 0);
> @@ -655,7 +655,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
>  					     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags);
> +		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags, vm_flags);
>  
>  	return slice_get_unmapped_area(addr0, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 1);
> diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
> index c4d34abc45d4..07bb8d4181d7 100644
> --- a/include/linux/sched/mm.h
> +++ b/include/linux/sched/mm.h
> @@ -204,11 +204,11 @@ unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm,
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags);
> +			  unsigned long flags, vm_flags_t vm_flags);
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags);
> +				  unsigned long flags, vm_flags_t vm_flags);
>  #else
>  static inline void arch_pick_mmap_layout(struct mm_struct *mm,
>  					 struct rlimit *rlim_stack) {}
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7528146f886f..b06ba847c96e 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1789,7 +1789,7 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info)
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags)
> +			  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct mm_struct *mm = current->mm;
>  	struct vm_area_struct *vma, *prev;
> @@ -1823,7 +1823,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  		       unsigned long len, unsigned long pgoff,
>  		       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area(filp, addr, len, pgoff, flags,
> +					 vm_flags);
>  }
>  #endif
>  
> @@ -1834,7 +1835,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags)
> +				  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct vm_area_struct *vma, *prev;
>  	struct mm_struct *mm = current->mm;
> @@ -1887,7 +1888,8 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  			       unsigned long len, unsigned long pgoff,
>  			       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags,
> +						 vm_flags);
>  }
>  #endif
>  
> 
> -- 
> 2.39.2
>
Re: [PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area()
Posted by Lorenzo Stoakes 1 year, 3 months ago 
On Mon, Sep 02, 2024 at 08:08:14PM GMT, Mark Brown wrote:
> In preparation for using vm_flags to ensure guard pages for shadow stacks
> supply them as an argument to generic_get_unmapped_area(). The only user
> outside of the core code is the PowerPC book3s64 implementation which is
> trivially wrapping the generic implementation in the radix_enabled() case.
>
> Signed-off-by: Mark Brown <broonie@kernel.org>

Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> (for mm/mmap.c part)

> ---
>  arch/powerpc/mm/book3s64/slice.c |  4 ++--
>  include/linux/sched/mm.h         |  4 ++--
>  mm/mmap.c                        | 10 ++++++----
>  3 files changed, 10 insertions(+), 8 deletions(-)
>
> diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c
> index ada6bf896ef8..87307d0fc3b8 100644
> --- a/arch/powerpc/mm/book3s64/slice.c
> +++ b/arch/powerpc/mm/book3s64/slice.c
> @@ -641,7 +641,7 @@ unsigned long arch_get_unmapped_area(struct file *filp,
>  				     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +		return generic_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags);
>
>  	return slice_get_unmapped_area(addr, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 0);
> @@ -655,7 +655,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
>  					     vm_flags_t vm_flags)
>  {
>  	if (radix_enabled())
> -		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags);
> +		return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags, vm_flags);
>
>  	return slice_get_unmapped_area(addr0, len, flags,
>  				       mm_ctx_user_psize(&current->mm->context), 1);
> diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
> index c4d34abc45d4..07bb8d4181d7 100644
> --- a/include/linux/sched/mm.h
> +++ b/include/linux/sched/mm.h
> @@ -204,11 +204,11 @@ unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm,
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags);
> +			  unsigned long flags, vm_flags_t vm_flags);
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags);
> +				  unsigned long flags, vm_flags_t vm_flags);
>  #else
>  static inline void arch_pick_mmap_layout(struct mm_struct *mm,
>  					 struct rlimit *rlim_stack) {}
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7528146f886f..b06ba847c96e 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1789,7 +1789,7 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info)
>  unsigned long
>  generic_get_unmapped_area(struct file *filp, unsigned long addr,
>  			  unsigned long len, unsigned long pgoff,
> -			  unsigned long flags)
> +			  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct mm_struct *mm = current->mm;
>  	struct vm_area_struct *vma, *prev;
> @@ -1823,7 +1823,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  		       unsigned long len, unsigned long pgoff,
>  		       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area(filp, addr, len, pgoff, flags,
> +					 vm_flags);
>  }
>  #endif
>
> @@ -1834,7 +1835,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
>  unsigned long
>  generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  				  unsigned long len, unsigned long pgoff,
> -				  unsigned long flags)
> +				  unsigned long flags, vm_flags_t vm_flags)
>  {
>  	struct vm_area_struct *vma, *prev;
>  	struct mm_struct *mm = current->mm;
> @@ -1887,7 +1888,8 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
>  			       unsigned long len, unsigned long pgoff,
>  			       unsigned long flags, vm_flags_t vm_flags)
>  {
> -	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
> +	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags,
> +						 vm_flags);
>  }
>  #endif
>
>
> --
> 2.39.2
>

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