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Date:   Thu, 8 Jun 2023 18:23:19 -0700 (PDT)
From:   Hugh Dickins <hughd@google.com>
To:     Andrew Morton <akpm@linux-foundation.org>
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Subject: [PATCH v2 13/32] mm/hmm: retry if pte_offset_map() fails
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Message-ID: <d6c6dd68-25d4-653b-f94b-a45c53ee04b@google.com>
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Precedence: bulk

hmm_vma_walk_pmd() is called through mm_walk, but already has a goto
again loop of its own, so take part in that if pte_offset_map() fails.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
---
 mm/hmm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/hmm.c b/mm/hmm.c
index e23043345615..b1a9159d7c92 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -381,6 +381,8 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
 	}
 
 	ptep = pte_offset_map(pmdp, addr);
+	if (!ptep)
+		goto again;
 	for (; addr < end; addr += PAGE_SIZE, ptep++, hmm_pfns++) {
 		int r;
 
-- 
2.35.3