Re: [PATCH] aarch64: fix errno address calculation in SYSCALL_ERROR_HANDLER()

[Adhemerval Zanella <adhemerval dot zanella at linaro dot org>]

If it is an user visible issue it requires a bugzilla report (although I am not
sure in this situation since I think this issue should arise only for ilp32).

Also, errno for mmap in particular should be covered on 'posix/tst-mmap.c'.
When/how exactly this issues is triggered? It could be a good thing to have
at least a regression check or increase coverage in an existing test.

On 07/02/2017 09:48, Yury Norov wrote:
> This patch fixes the last regression in LTP lite scenario (mmap16) comparing
> to lp64 in my source trees [1, 2]. The fix has been suggested back in 2015 [3]
> but was never applied, so I reinvented the weel while debugging mmap16.
> 
> [1] https://github.com/norov/glibc/tree/dev9
> [2] https://github.com/norov/linux/tree/ilp32-20170203
> [3] https://sourceware.org/ml/libc-alpha/2015-03/msg00587.html
> 
> 	* sysdeps/unix/sysv/linux/aarch64/sysdep.h: use PTR_REG() for offset
> 	calculation in SYSCALL_ERROR_HANDLER().
> 
> ---
>  sysdeps/unix/sysv/linux/aarch64/sysdep.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sysdeps/unix/sysv/linux/aarch64/sysdep.h b/sysdeps/unix/sysv/linux/aarch64/sysdep.h
> index 1ffabc2..d926e19 100644
> --- a/sysdeps/unix/sysv/linux/aarch64/sysdep.h
> +++ b/sysdeps/unix/sysv/linux/aarch64/sysdep.h
> @@ -108,7 +108,7 @@
>  .Lsyscall_error:						\
>  	adrp	x1, :gottprel:errno;				\
>  	neg	w2, w0;						\
> -	ldr	x1, [x1, :gottprel_lo12:errno];			\
> +	ldr	PTR_REG (1), [x1, :gottprel_lo12:errno];	\
>  	mrs	x3, tpidr_el0;					\
>  	mov	x0, -1;						\
>  	str	w2, [x1, x3];					\
>