When the TRBE driver fails to allocate a buffer, it currently returns the error code "-ENOMEM". However, the caller etm_setup_aux() only checks for a NULL pointer, so it misses the error. As a result, the driver continues and eventually causes a kernel panic.
Fix this by returning a NULL pointer from arm_trbe_alloc_buffer() on allocation failures. This allows that the callers can properly handle the failure.
Fixes: 3fbf7f011f24 ("coresight: sink: Add TRBE driver") Reported-by: Tamas Zsoldos tamas.zsoldos@arm.com Signed-off-by: Leo Yan leo.yan@arm.com --- Changes in v2: - Fix TRBE driver instead of changing coresight-etm-perf.c. - Link to v1: https://lore.kernel.org/r/20250904-cs_etm_auxsetup_fix_error_handling-v1-1-e... --- drivers/hwtracing/coresight/coresight-trbe.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c index 10f3fb401edf6a00b24b38cdaa7c2865e7a191ac..8f9bbef71f236b327d35a288689df9b0dd8ff3f4 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.c +++ b/drivers/hwtracing/coresight/coresight-trbe.c @@ -748,12 +748,12 @@ static void *arm_trbe_alloc_buffer(struct coresight_device *csdev,
buf = kzalloc_node(sizeof(*buf), GFP_KERNEL, trbe_alloc_node(event)); if (!buf) - return ERR_PTR(-ENOMEM); + return NULL;
pglist = kcalloc(nr_pages, sizeof(*pglist), GFP_KERNEL); if (!pglist) { kfree(buf); - return ERR_PTR(-ENOMEM); + return NULL; }
for (i = 0; i < nr_pages; i++) @@ -763,7 +763,7 @@ static void *arm_trbe_alloc_buffer(struct coresight_device *csdev, if (!buf->trbe_base) { kfree(pglist); kfree(buf); - return ERR_PTR(-ENOMEM); + return NULL; } buf->trbe_limit = buf->trbe_base + nr_pages * PAGE_SIZE; buf->trbe_write = buf->trbe_base;
--- base-commit: fa71e9cb4cfa59abb196229667ec84929bdc18fe change-id: 20250904-cs_etm_auxsetup_fix_error_handling-cb7e07ed9adf
Best regards,