On 19/05/2026 16:48, Yeoreum Yun wrote:
TCRSEQEVR<n> is implemented only when TCRIDR5.NUMSEQSTATE is 0b100, in which case n ranges from 0 to 2; otherwise, TCRIDR5.NUMSEQSTATE is 0b000.
Therefore, drvdata->nrseqstate should be checked before entering the loop.
for (i = 0; i < drvdata->nrseqstate - 1; i++)
Wouldn't that check cover the case ? (provided i is signed int ?)
Suzuki
Link: https://developer.arm.com/documentation/ihi0064/latest/ [0] Fixes: 2e1cdfe184b5 ("coresight-etm4x: Adding CoreSight ETM4x driver") Reviewed-by: Leo Yan leo.yan@arm.com Signed-off-by: Yeoreum Yun yeoreum.yun@arm.com
.../hwtracing/coresight/coresight-etm4x-core.c | 18 ++++++++++-------- .../coresight/coresight-etm4x-sysfs.c | 2 ++ 2 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 1e3b0344dc00..94b9385e964a 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -542,9 +542,11 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata) etm4x_relaxed_write32(csa, config->vissctlr, TRCVISSCTLR); if (drvdata->nr_pe_cmp) etm4x_relaxed_write32(csa, config->vipcssctlr, TRCVIPCSSCTLR);
- for (i = 0; i < drvdata->nrseqstate - 1; i++)
etm4x_relaxed_write32(csa, config->seq_ctrl[i], TRCSEQEVRn(i));
- if (drvdata->nrseqstate) {
for (i = 0; i < drvdata->nrseqstate - 1; i++)etm4x_relaxed_write32(csa, config->seq_ctrl[i], TRCSEQEVRn(i));- etm4x_relaxed_write32(csa, config->seq_rst, TRCSEQRSTEVR); etm4x_relaxed_write32(csa, config->seq_state, TRCSEQSTR); }
@@ -1896,10 +1898,10 @@ static int etm4_cpu_save(struct coresight_device *csdev) if (drvdata->nr_pe_cmp) state->trcvipcssctlr = etm4x_read32(csa, TRCVIPCSSCTLR);
- for (i = 0; i < drvdata->nrseqstate - 1; i++)
state->trcseqevr[i] = etm4x_read32(csa, TRCSEQEVRn(i));- if (drvdata->nrseqstate) {
for (i = 0; i < drvdata->nrseqstate - 1; i++)state->trcseqevr[i] = etm4x_read32(csa, TRCSEQEVRn(i));- state->trcseqrstevr = etm4x_read32(csa, TRCSEQRSTEVR); state->trcseqstr = etm4x_read32(csa, TRCSEQSTR); }
@@ -2009,10 +2011,10 @@ static void etm4_cpu_restore(struct coresight_device *csdev) if (drvdata->nr_pe_cmp) etm4x_relaxed_write32(csa, state->trcvipcssctlr, TRCVIPCSSCTLR);
- for (i = 0; i < drvdata->nrseqstate - 1; i++)
etm4x_relaxed_write32(csa, state->trcseqevr[i], TRCSEQEVRn(i));- if (drvdata->nrseqstate) {
for (i = 0; i < drvdata->nrseqstate - 1; i++)etm4x_relaxed_write32(csa, state->trcseqevr[i], TRCSEQEVRn(i));- etm4x_relaxed_write32(csa, state->trcseqrstevr, TRCSEQRSTEVR); etm4x_relaxed_write32(csa, state->trcseqstr, TRCSEQSTR); }
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c index e9eeea6240d5..0e1ad175aa1e 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c @@ -1395,6 +1395,8 @@ static ssize_t seq_idx_store(struct device *dev, struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent); struct etmv4_config *config = &drvdata->config;
- if (!drvdata->nrseqstate)
return -ENOTSUPP;