When the ETR is used in perf mode with a larger buffer (configured via sysfs or the default size of 1M) than the perf aux buffer size, we end up inserting the barrier packet at the wrong offset, while moving the offset forward. i.e, instead of the "new moved offset", we insert it at the current hardware buffer offset. These packets will not be visible as they are never copied and could lead to corruption in the trace decoding side, as the decoder is not aware that it needs to reset the decoding.
Fixes: ec13c78d7b45 ("coresight: tmc-etr: Add barrier packets when moving offset forward") Reported-by: Al Grant al.grant@arm.com Tested-by: Mike Leach mike.leach@arm.com Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com --- drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index a31a4d7ae25e..bf5230e39c5b 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1552,7 +1552,7 @@ tmc_update_etr_buffer(struct coresight_device *csdev,
/* Insert barrier packets at the beginning, if there was an overflow */ if (lost) - tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset); + tmc_etr_buf_insert_barrier_packet(etr_buf, offset); tmc_etr_sync_perf_buffer(etr_perf, offset, size);
/*
On Mon, Nov 30, 2020 at 02:36:02PM +0000, Suzuki K Poulose wrote:
When the ETR is used in perf mode with a larger buffer (configured via sysfs or the default size of 1M) than the perf aux buffer size, we end up inserting the barrier packet at the wrong offset, while moving the offset forward. i.e, instead of the "new moved offset", we insert it at the current hardware buffer offset. These packets will not be visible as they are never copied and could lead to corruption in the trace decoding side, as the decoder is not aware that it needs to reset the decoding.
Fixes: ec13c78d7b45 ("coresight: tmc-etr: Add barrier packets when moving offset forward") Reported-by: Al Grant al.grant@arm.com Tested-by: Mike Leach mike.leach@arm.com Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com
drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index a31a4d7ae25e..bf5230e39c5b 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1552,7 +1552,7 @@ tmc_update_etr_buffer(struct coresight_device *csdev, /* Insert barrier packets at the beginning, if there was an overflow */ if (lost)
tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset);
tmc_etr_buf_insert_barrier_packet(etr_buf, offset);
I have applied this patch.
Thanks, Mathieu
tmc_etr_sync_perf_buffer(etr_perf, offset, size); /* -- 2.24.1
-
Mathieu Poirier -
Suzuki K Poulose