summaryrefslogtreecommitdiffstats
path: root/lib/memweight.c
diff options
context:
space:
mode:
authorFan Wu <fanwu01@zju.edu.cn>2026-08-20 13:53:06 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-09-01 16:50:04 +0200
commit263f7d61a4201cde16849b2d016251806e7418be (patch)
tree861df7c5b878b85741cf319ece81111b4c41c3b1 /lib/memweight.c
downloadlinux-stable-263f7d61a4201cde16849b2d016251806e7418be.tar.gz
linux-stable-263f7d61a4201cde16849b2d016251806e7418be.zip
usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stopgrafted
cc_debounce_dwork is queued from the set_cc() and start_toggling() callbacks, which run from TCPM's kthread worker. port_stop() returns before tcpm_unregister_port() destroys that worker. Flushing the worker during unregister may therefore run a callback which queues the delayed work after port_stop() has returned. The delayed work can then run after devres has freed pmic_typec_port. Use disable_delayed_work_sync() in port_stop() to cancel a pending instance and prevent the TCPM callbacks from queueing another one. This issue was found by an in-house static analysis tool. Fixes: a4422ff22142 ("usb: typec: qcom: Add Qualcomm PMIC Type-C driver") Cc: stable <stable@kernel.org> # v6.10+ Assisted-by: Codex:gpt-5.6 Signed-off-by: Fan Wu <fanwu01@zju.edu.cn> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Link: https://patch.msgid.link/20260820135307.153773-2-fanwu01@zju.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib/memweight.c')
-rw-r--r--lib/memweight.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/lib/memweight.c b/lib/memweight.c
new file mode 100644
index 000000000..94dd72cca
--- /dev/null
+++ b/lib/memweight.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/export.h>
+#include <linux/bug.h>
+#include <linux/bitmap.h>
+
+/**
+ * memweight - count the total number of bits set in memory area
+ * @ptr: pointer to the start of the area
+ * @bytes: the size of the area
+ */
+size_t memweight(const void *ptr, size_t bytes)
+{
+ size_t ret = 0;
+ size_t longs;
+ const unsigned char *bitmap = ptr;
+
+ for (; bytes > 0 && ((unsigned long)bitmap) % sizeof(long);
+ bytes--, bitmap++)
+ ret += hweight8(*bitmap);
+
+ longs = bytes / sizeof(long);
+ if (longs) {
+ BUG_ON(longs >= INT_MAX / BITS_PER_LONG);
+ ret += bitmap_weight((unsigned long *)bitmap,
+ longs * BITS_PER_LONG);
+ bytes -= longs * sizeof(long);
+ bitmap += longs * sizeof(long);
+ }
+ /*
+ * The reason that this last loop is distinct from the preceding
+ * bitmap_weight() call is to compute 1-bits in the last region smaller
+ * than sizeof(long) properly on big-endian systems.
+ */
+ for (; bytes > 0; bytes--, bitmap++)
+ ret += hweight8(*bitmap);
+
+ return ret;
+}
+EXPORT_SYMBOL(memweight);