On 8/11/20 10:16 AM, Andrew Morton wrote:
On Fri, 7 Aug 2020 13:29:33 +0530 "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> wrote:
Like zap_pte_range add cond_resched so that we can avoid softlockups as reported
below. On non-preemptible kernel with large I/O map region (like the one we get
when using persistent memory with sector mode), an unmap of the namespace can report
below softlockups.
...
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -102,6 +102,8 @@ static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
if (pmd_none_or_clear_bad(pmd))
continue;
vunmap_pte_range(pmd, addr, next, mask);
+
+ cond_resched();
} while (pmd++, addr = next, addr != end);
}
That looks sane. I'll aim for merging it in 5.9-rc2ish, with a
cc:stable, OK?
Sure. I was not so particular about stable because it was only a
softlockup warning.
-aneesh
