From: pengdonglin <[email protected]> The BTF-aware funcgraph-retval formatter currently treats all pointer returns as hexadecimal values. Error pointers returned with ERR_PTR() therefore appear as high unsigned addresses in smart mode, obscuring the underlying errno.
Recognize error-pointer values for pointer return types in btf_trim_retval() and select signed decimal formatting. Before: trim_retval_ptr_error(); /* ret=0xffffffffffffffea */ After: trim_retval_ptr_error(); /* ret=-22 */ Users who need to inspect the raw encoded value can enable funcgraph-retval-hex, which produces: trim_retval_ptr_error(); /* ret=0xffffffffffffffea */ Signed-off-by: pengdonglin <[email protected]> --- kernel/trace/trace_btf.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/trace/trace_btf.c b/kernel/trace/trace_btf.c index bcf65fec7bb1..1201105aa48b 100644 --- a/kernel/trace/trace_btf.c +++ b/kernel/trace/trace_btf.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/btf.h> +#include <linux/err.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/kallsyms.h> @@ -197,6 +198,12 @@ void btf_trim_retval(unsigned long func, unsigned long *retval, bool *print_retv if (signed_type && !hex) *retval = sign_extend64(*retval, msb); break; + case BTF_KIND_PTR: + if (!hex && IS_ERR_VALUE(*retval)) + *fmt = RETVAL_FMT_DEC; + else + *fmt = RETVAL_FMT_HEX; + break; default: *fmt = RETVAL_FMT_HEX; break; -- 2.34.1
