Fix hppa/ia64/microblaze executable stack default (bug 22156)

[John David Anglin]

On 2017-09-22, at 4:11 PM, Joseph Myers wrote:

> Given what Andreas said at 
> <https://gcc.gnu.org/ml/gcc-patches/2017-09/msg01220.html>, does this mean 
> there are other causes of executable stacks in the kernel, such as 
> VM_STACK_DEFAULT_FLAGS?  If so, maybe hppa and microblaze do in fact need 
> the GCC patch rather than the glibc one?

VM_STACK_DEFAULT_FLAGS defaults to VM_DATA_DEFAULT_FLAGS when it is
not defined, and it is not defined on hppa.

On hppa,  VM_DATA_DEFAULT_FLAGS, and it is:

#define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE | VM_EXEC | \
                                 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)

Dave
--
John David Anglin	dave.anglin@bell.net