From: Mieczyslaw Nalewaj Date: Sun, 26 Oct 2025 10:36:02 +0100 Subject: [PATCH] mt7620: conditional stack align This patch avoids applying arch_align_stack() and PAGE_ALIGN() in the exec path on CONFIG_NET_RALINK_MT7620 builds. Many ports (including mt7620) implement only micro-randomization inside arch_align_stack() (random offset < PAGE_SIZE and then align-down to small alignment). Callers that immediately apply PAGE_ALIGN() will round that micro-offset back to the original page boundary, so invoking arch_align_stack() then PAGE_ALIGN() is pointless and can be avoided on the affected platform. Signed-off-by: Mieczyslaw Nalewaj --- a/fs/exec.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/exec.c +++ b/fs/exec.c @@ -750,8 +750,10 @@ int setup_arg_pages(struct linux_binprm mm->arg_start = bprm->p - stack_shift; bprm->p = vma->vm_end - stack_shift; #else +#ifndef CONFIG_NET_RALINK_MT7620 stack_top = arch_align_stack(stack_top); stack_top = PAGE_ALIGN(stack_top); +#endif if (unlikely(stack_top < mmap_min_addr) || unlikely(vma->vm_end - vma->vm_start >= stack_top - mmap_min_addr))