Re: [PATCH v3 1/3] mm/memory-failure: userspace controls soft-offlining pages

On Mon, Jun 17, 2024 at 05:05:43PM +0000, Jiaqi Yan wrote:

• • Returns 0 on success

• •     -EOPNOTSUPP for hwpoison_filter() filtered the error event
    

• • Returns 0 on success,

• •     -EOPNOTSUPP for hwpoison_filter() filtered the error event,
    

• •     -EOPNOTSUPP if disabled by /proc/sys/vm/enable_soft_offline,
    

  •     < 0 otherwise negated errno.
    

  • Soft offline a page, by migration or invalidation,

@@ -2783,6 +2795,12 @@ int soft_offline_page(unsigned long pfn, int flags) return -EIO; }

• if (!sysctl_enable_soft_offline) {

• pr_info("%#lx: OS-wide disabled\n", pfn);
  

• put_ref_page(pfn, flags);
  

• return -EOPNOTSUPP;
  

• }

We should not be doing anything if soft_offline is disabled, so this check should be placed upfront, at the very beginning of the function. Then you can remove the 'put_ref_page' call.