From: Sven Schnelle <svens@linux.ibm.com>
Date: Thu, 13 Jul 2023 13:54:23 +0000 (+0200)
Subject: s390/mm: fix per vma lock fault handling
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7686762d1ed092db4d120e29b565712c969dc075;p=linux.git

s390/mm: fix per vma lock fault handling

With per-vma locks, handle_mm_fault() may return non-fatal error
flags. In this case the code should reset the fault flags before
returning.

Fixes: e06f47a16573 ("s390/mm: try VMA lock-based page fault handling first")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index dbe8394234e2b..2f123429a291b 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -421,6 +421,8 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access)
 	vma_end_read(vma);
 	if (!(fault & VM_FAULT_RETRY)) {
 		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+		if (likely(!(fault & VM_FAULT_ERROR)))
+			fault = 0;
 		goto out;
 	}
 	count_vm_vma_lock_event(VMA_LOCK_RETRY);