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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: Mh8/a30XnhaUTl6KlOOgNBi9FTScd1+H6uDMZ1f7xN/FvipTwUkuVOpDsguo2pOcPgjBTguBC9bEed9ShgVduEzl07F1JlXhUyJ0Jxvb7fb4H+DmUmKstzwoA8MEiru2Nncipm4yi4yTbTc6OrTKTQ5b1NSHHdYHhlTJd0XyAB6AzgJiaIpXQbBusAvB5C5ZB7dmLHjgiY1BwysiFPOlvbtYdNGxllDTC9QHekWxfBoyC6LAh2wTP+CGcLRUOrN0IVzTsXIzVSz4mnM2LStny0Q7RYsYDdE1Mfs+NcvtJsLwGyKzaroOHDuouTocbUNAGQLbSugqz5potWazhbwadG4WhP+ehSq8VX6rubnIZiEeDQ+R00/Vc1yhDb0SeRbumXyAcnKxpCL7oqKNMLVBvK6e2+xFyqhleMHlk1lAaOk+v3XBSkMrZLErg1Hv4D8I X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Sep 2026 11:15:59.7492 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c0ab44c5-4c34-4189-37f2-08df157637f6 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[4.158.2.129];Helo=[outbound-uk1.az.dlp.m.darktrace.com] X-MS-Exchange-CrossTenant-AuthSource: MAD0EPF000008A8.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM0PR08MB5346 Reviewed-by: Mike Leach On 9/15/26 12:34, Yeoreum Yun wrote: > cntr_val are overwritten with the values read from the corresponding > registers by etm_disable_hw() when the session is disabled. > > This means that any changes to this value made while the session is > enabled would be lost when the session is disabled. > > Also, reset shouldn't be called while session is enabled. > > Therefore, prohibit modifying cntr_val and reset while the session is enabled. > > Signed-off-by: Yeoreum Yun > --- > drivers/hwtracing/coresight/coresight-etm3x-sysfs.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > index b3c67e96a82a4..d4846d6364945 100644 > --- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > +++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > @@ -74,6 +74,8 @@ static ssize_t reset_store(struct device *dev, > ret = kstrtoul(buf, 16, &val); > if (ret) > return ret; > + if (coresight_get_mode(drvdata->csdev)) > + return -EBUSY; > > if (val) { > spin_lock(&drvdata->spinlock); > @@ -744,6 +746,8 @@ static ssize_t cntr_val_store(struct device *dev, > ret = kstrtoul(buf, 16, &val); > if (ret) > return ret; > + if (coresight_get_mode(drvdata->csdev)) > + return -EBUSY; > > spin_lock(&drvdata->spinlock); > config->cntr_val[config->cntr_idx] = val; >