From c38b1e19485aaa820e52cfe162525a8af67563da Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 14 Jul 2026 13:56:25 +0100 Subject: [PATCH] firmware: arm_scmi: Avoid IDR updates while cleaning channels scmi_cleanup_channels() walks the TX/RX channel IDRs with idr_for_each() to free transport resources and destroy the dedicated transport devices before calling idr_destroy(). The destroy callback removed each entry from the same IDR being walked. That is not needed for this cleanup path, and it is unsafe because idr_for_each() has not advanced its radix-tree iterator while the callback is running. Removing the current entry from the callback can invalidate the iterator state. The callback also cannot be protected by rcu_read_lock(), because scmi_device_destroy() may sleep. Leave IDR teardown to the following idr_destroy() call and keep the callback limited to device destruction. Fixes: 05a2801d8b90 ("firmware: arm_scmi: Use dedicated devices to initialize channels") Reported-by: Sashiko Link: https://patch.msgid.link/20260714-scmi_core_fixes-v6-6-3afe499d46e3@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/driver.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 6ee2152f6b01..d17559c897a9 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -2885,7 +2885,7 @@ static int scmi_channels_setup(struct scmi_info *info) return 0; } -static int scmi_chan_destroy(int id, void *p, void *idr) +static int scmi_chan_destroy(int id, void *p, void *data) { struct scmi_chan_info *cinfo = p; @@ -2898,8 +2898,6 @@ static int scmi_chan_destroy(int id, void *p, void *idr) cinfo->dev = NULL; } - idr_remove(idr, id); - return 0; }