On 10/10/2026 2:46 AM, Dmitry Osipenko wrote:
09.10.2026 21:38, Dmitry Osipenko пишет:
24.09.2026 12:55, Honglei Huang пишет:
+ mm = current->mm;
+ mmgrab(mm);
+ lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ new_pinned = atomic64_add_return(userptr->npages, &mm->pinned_vm);
+ if (new_pinned < 0 ||
+ (new_pinned > lock_limit && !capable(CAP_IPC_LOCK))) {
+ atomic64_sub(userptr->npages, &mm->pinned_vm)
At a quick glance over other kernel code touching pinned_vm, nobody else
check for new_pinned < 0 and then doing atomic64_sub() for the negative
value will be incorrect.
Though no, negative will restore pinned_vm. Still neg looks confusing
and shouldn't be needed as such overflow shouldn't be possible.
Got it will remove this check in next version
Regards,
Honglei
