Re: Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
> How do you end up with Device nGnRnE in user space? I thought we should > have got some guard page. I guess it is a device file that is mmaped in the user space and later remapped in the kernel using pgprot_noncached(). I can't find the code that inserts a guard page in between vma's can

Re: Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
> How do you end up with Device nGnRnE in user space? I thought we should > have got some guard page. I guess it is a device file that is mmaped in the user space and later remapped in the kernel using pgprot_noncached(). I can't find the code that inserts a guard page in between vma's can

Re: Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
> How do you end up with Device nGnRnE in user space? I thought we should > have got some guard page. I guess it is a device file that is mmaped in the user space and later remapped in the kernel using pgprot_noncached(). I can't find the code that inserts a guard page in between vma's can you

Re: Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
> How do you end up with Device nGnRnE in user space? I thought we should > have got some guard page. I guess it is a device file that is mmaped in the user space and later remapped in the kernel using pgprot_noncached(). I can't find the code that inserts a guard page in between vma's can you

Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread Catalin Marinas
On Mon, Feb 15, 2016 at 08:58:32AM +, EunTaik Lee wrote: > Userspace memory is mapped as below: > F2A7F000--F2A7 Normal Memory > F2A8--F2A80FFF Device nGnRnE How do you end up with Device nGnRnE in user space? I thought we should have got some guard page. > And that userspace

Re: [PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread Catalin Marinas
On Mon, Feb 15, 2016 at 08:58:32AM +, EunTaik Lee wrote: > Userspace memory is mapped as below: > F2A7F000--F2A7 Normal Memory > F2A8--F2A80FFF Device nGnRnE How do you end up with Device nGnRnE in user space? I thought we should have got some guard page. > And that userspace

[PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
Userspace memory is mapped as below: F2A7F000--F2A7 Normal Memory F2A8--F2A80FFF Device nGnRnE And that userspace application makes a system call as below: -009 |do_strncpy_from_user(inline) -009 |strncpy_from_user() -010 |getname_flags() -011 |user_path_at_empty() -012 |user_path_at()

[PATCH RESEND] arm64: add alignment fault hanling

2016-02-15 Thread EunTaik Lee
Userspace memory is mapped as below: F2A7F000--F2A7 Normal Memory F2A8--F2A80FFF Device nGnRnE And that userspace application makes a system call as below: -009 |do_strncpy_from_user(inline) -009 |strncpy_from_user() -010 |getname_flags() -011 |user_path_at_empty() -012 |user_path_at()