On 2024/5/16 16:26, Oscar Salvador wrote:
> On Wed, May 15, 2024 at 05:55:39PM +0200, David Hildenbrand wrote:
>>> + if (is_huge_zero_folio(folio)) {
>>> + unpoison_pr_info("Unpoison: huge zero page is not supported %#lx\n",
>>> + pfn, &unpoison_rs);
>>> + goto unlock_mutex;
>>> + }
>>> +
>
> Sorry for spamming your reply David, but for some unknown reason I am not able
> to find the original patch in my mailbox, in none of the two accountes I am
> subscribed, so I guess I will have to reply here.
>
> Just two things
>
> 1) We do not care if someone grabs a refcount for huge_zero_folio,
> because since it is not supported anyway the outcome will not change.
> Also, AFAIK, there is no chance we can unpoison that folio.
> Therefore, I would just lift the check two blocks and place it right after
> the hw_memory_failure check.
>
> 2) The whole thing is unsupported, but you will return -EBUSY while you
> should be returning -EOPNOTSUPP AFAICS.
>
Thanks for your comment. Do you mean something like below?
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 16ada4fb02b7..a9fe9eda593f 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2546,6 +2546,13 @@ int unpoison_memory(unsigned long pfn)
goto unlock_mutex;
}
+ if (is_huge_zero_folio(folio)) {
+ unpoison_pr_info("Unpoison: huge zero page is not supported %#lx\n",
+ pfn, &unpoison_rs);
+ ret = -EOPNOTSUPP;
+ goto unlock_mutex;
+ }
+
if (!PageHWPoison(p)) {
unpoison_pr_info("Unpoison: Page was already unpoisoned %#lx\n",
pfn, &unpoison_rs);
Thanks.
.
> with that you can add:
>
> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx>
>
>
>
