[PATCH 6.1 0917/1191] coresight: etm4x: fix wrong check of etm4x_sspcicrn_present()

From
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date
2026-09-12 16:37:27
Also in
linux-patches
Reply to
Greg Kroah-Hartman, 2026-09-12
6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yeoreum Yun <redacted>

[ Upstream commit 0e1cd4270b42a257c139165622091e1e8c7104a7 ]

According to Embedded Trace Macrocell Architecture Specification
ETMv4.0 to ETM4.6 [0], TRCSSPCICR<n> is present only if all of
the following are true:

  - TRCIDR4.NUMSSCC > n.
  - TRCIDR4.NUMPC > 0b0000.
  - TRCSSCSR<n>.PC == 0b1.

Comment for etm4x_sspcicrn_present() is align with the specification.
However, the check should use drvdata->nr_pe_cmp to check TRCIDR4.NUMPC
not nr_pe.

Link: https://developer.arm.com/documentation/ihi0064/latest/ [0]
Fixes: f6a18f354c58 ("coresight: etm4x: Handle access to TRCSSPCICRn")
Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Yeoreum Yun <redacted>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20260725113645.57519-2-yeoreum.yun@arm.com (local)
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index b2c55cc45a11f..fa2fe4ff236da 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -82,7 +82,7 @@ struct etm4_init_arg {
 static inline bool etm4x_sspcicrn_present(struct etmv4_drvdata *drvdata, int n)
 {
 	return (n < drvdata->nr_ss_cmp) &&
-	       drvdata->nr_pe &&
+	       drvdata->nr_pe_cmp &&
 	       (drvdata->config.ss_status[n] & TRCSSCSRn_PC);
 }
 
-- 
2.53.0


Thread (1,211 messages) 1,211 messages, 13 authors, last reply 2026-09-21
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