Re: [PATCH v8 1/3] revocable: Revocable resource management
From: Bartosz Golaszewski <brgl@kernel.org>
Date: 2026-02-16 16:37:53
Also in:
chrome-platform, driver-core, linux-kselftest, lkml
On Fri, 13 Feb 2026 10:23:05 +0100, Tzung-Bi Shih [off-list ref] said:
The "revocable" mechanism is a synchronization primitive designed to manage safe access to resources that can be asynchronously removed or invalidated. Its primary purpose is to prevent Use-After-Free (UAF) errors when interacting with resources whose lifetimes are not guaranteed to outlast their consumers.
[snip]
quoted hunk ↗ jump to hunk
diff --git a/include/linux/revocable.h b/include/linux/revocable.h +
[snip]
+/**
+ * struct revocable_consumer - A handle for resource consumer.
+ * @rp: The pointer of resource provider.
+ * @idx: The index for the SRCU critical section.
+ */
+struct revocable_consumer {
+ struct revocable *rp;
+ int idx;
+};
+
+void revocable_get(struct revocable *rp);
+void revocable_put(struct revocable *rp);
+struct revocable *revocable_alloc(void *res);
Is there any reason why we couldn't do:
int revocable_init(struct revocable *rp, void *res);
and then:
struct gpio_device {
struct revocable rp;
...
};
revocable_init(&gdev->rp, gc);
? It would be functionally equivalent to what we're doing now in GPIO.
Bartosz