From: Suzuki K Poulose Date: Fri, 6 May 2016 14:35:50 +0000 (+0100) Subject: coresight: Handle build path error X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=5014e904681ddbdf663bb20f134eb053ddccb181;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git coresight: Handle build path error Enabling a component via sysfs (echo 1 > enable_source), would trigger building a path from the enabled sources to the sink. If there is an error in the process (e.g, sink not enabled or the device (CPU corresponding to ETM) is not online), we never report failure, except for leaving a message in the dmesg. Do proper error checking for the build path and return the error. Before: $ echo 0 > /sys/devices/system/cpu/cpu2/online $ echo 1 > /sys/devices/cs_etm/cpu2/enable_source $ echo $? 0 After: $ echo 0 > /sys/devices/system/cpu/cpu2/online $ echo 1 > /sys/devices/cs_etm/cpu2/enable_source -bash: echo: write error: No such device or address Signed-off-by: Suzuki K Poulose Acked-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 0fdaaf4a8994..d08d1ab9bba5 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -425,6 +425,7 @@ out: struct list_head *coresight_build_path(struct coresight_device *csdev) { struct list_head *path; + int rc; path = kzalloc(sizeof(struct list_head), GFP_KERNEL); if (!path) @@ -432,9 +433,10 @@ struct list_head *coresight_build_path(struct coresight_device *csdev) INIT_LIST_HEAD(path); - if (_coresight_build_path(csdev, path)) { + rc = _coresight_build_path(csdev, path); + if (rc) { kfree(path); - path = NULL; + return ERR_PTR(rc); } return path; @@ -507,8 +509,9 @@ int coresight_enable(struct coresight_device *csdev) goto out; path = coresight_build_path(csdev); - if (!path) { + if (IS_ERR(path)) { pr_err("building path(s) failed\n"); + ret = PTR_ERR(path); goto out; }