riscv: align stack in clone [BZ #28702]
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dj/TryBot-apply_patch |
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Patch applied to master at the time it was sent
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dj/TryBot-32bit |
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Build for i686
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Commit Message
The RISC-V ABI [1] mandates that "the stack pointer shall be aligned to
a 128-bit boundary upon procedure entry". This as not the case in clone.
This fixes the misc/tst-misalign-clone-internal and
misc/tst-misalign-clone tests.
Fixes bug 28702.
[1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc
---
sysdeps/unix/sysv/linux/riscv/clone.S | 3 +++
1 file changed, 3 insertions(+)
Comments
I had thought it was the caller's responsibility to provide a properly
aligned stack, but I see that the x86-64 and aarch64 ports have been
similarly patched recently. So, LGTM.
On Wed, Dec 15, 2021 at 3:06 PM Aurelien Jarno <aurelien@aurel32.net> wrote:
>
> The RISC-V ABI [1] mandates that "the stack pointer shall be aligned to
> a 128-bit boundary upon procedure entry". This as not the case in clone.
>
> This fixes the misc/tst-misalign-clone-internal and
> misc/tst-misalign-clone tests.
>
> Fixes bug 28702.
>
> [1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc
> ---
> sysdeps/unix/sysv/linux/riscv/clone.S | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/sysdeps/unix/sysv/linux/riscv/clone.S b/sysdeps/unix/sysv/linux/riscv/clone.S
> index 12f91a20d3..161e83c7e3 100644
> --- a/sysdeps/unix/sysv/linux/riscv/clone.S
> +++ b/sysdeps/unix/sysv/linux/riscv/clone.S
> @@ -32,6 +32,9 @@
> .text
> LEAF (__clone)
>
> + /* Align stack to a 128-bit boundary as per RISC-V ABI. */
> + andi a1,a1,ALMASK
> +
> /* Sanity check arguments. */
> beqz a0,L (invalid) /* No NULL function pointers. */
> beqz a1,L (invalid) /* No NULL stack pointers. */
> --
> 2.33.0
>
@@ -32,6 +32,9 @@
.text
LEAF (__clone)
+ /* Align stack to a 128-bit boundary as per RISC-V ABI. */
+ andi a1,a1,ALMASK
+
/* Sanity check arguments. */
beqz a0,L (invalid) /* No NULL function pointers. */
beqz a1,L (invalid) /* No NULL stack pointers. */