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From: Dave Jiang <dave.jiang@intel.com>
To: nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org
Cc: dan.j.williams@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com
Subject: [PATCH] dax: Add direct_access() callback check for dax_direct_access()
Date: Fri,  6 Mar 2026 16:05:07 -0700	[thread overview]
Message-ID: <20260306230507.2149965-1-dave.jiang@intel.com> (raw)

__devm_create_dev_dax() calls alloc_dax() with the ops parameter passed
in as NULL. Therefore the ops pointer in dev_dax can be NULL. Add a
check in dax_direct_access() for ops and ops->direct_access() before
calling ops->direct_access().

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 drivers/dax/super.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index c00b9dff4a06..5cebaf11a58e 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -160,6 +160,9 @@ long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
 	if (nr_pages < 0)
 		return -EINVAL;
 
+	if (!dax_dev->ops || !dax_dev->ops->direct_access)
+		return -EOPNOTSUPP;
+
 	avail = dax_dev->ops->direct_access(dax_dev, pgoff, nr_pages,
 			mode, kaddr, pfn);
 	if (!avail)

base-commit: 11439c4635edd669ae435eec308f4ab8a0804808
-- 
2.53.0


             reply	other threads:[~2026-03-06 23:05 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-06 23:05 Dave Jiang [this message]
2026-03-09 16:58 ` [PATCH] dax: Add direct_access() callback check for dax_direct_access() Ira Weiny

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