Re: [PATCH 2/2] uprobes: add speculative lockless VMA-to-inode-to-uprobe resolution

[Oleg Nesterov]

On 09/05, Andrii Nakryiko wrote:
>
> +static struct uprobe *find_active_uprobe_speculative(unsigned long bp_vaddr)
> +{
> +	const vm_flags_t flags = VM_HUGETLB | VM_MAYEXEC | VM_MAYSHARE;
...
> +	if (!vm_file || (vma->vm_flags & flags) != VM_MAYEXEC)
> +		goto bail;

Not that this can really simplify your patch, feel free to ignore, but I don't
think you need to check vma->vm_flags.

Yes, find_active_uprobe_rcu() does the same valid_vma(vma, false) check, but it
too can/should be removed, afaics.

valid_vma(vma, false) makes sense in, say, unapply_uprobe() to quickly filter
out vma's which can't have this bp installed, but not in the handle_swbp() paths.

Oleg.