@@ -40,6 +40,7 @@ extern ssize_t cpumf_events_sysfs_show(struct device *dev,
extern unsigned long perf_instruction_pointer(struct pt_regs *regs);
extern unsigned long perf_misc_flags(struct pt_regs *regs);
#define perf_misc_flags(regs) perf_misc_flags(regs)
+#define perf_arch_bpf_user_pt_regs(regs) ®s->user_regs
/* Perf pt_regs extension for sample-data-entry indicators */
struct perf_sf_sde_regs {
@@ -74,9 +74,14 @@ enum {
*/
struct pt_regs
{
- unsigned long args[1];
- psw_t psw;
- unsigned long gprs[NUM_GPRS];
+ union {
+ user_pt_regs user_regs;
+ struct {
+ unsigned long args[1];
+ psw_t psw;
+ unsigned long gprs[NUM_GPRS];
+ };
+ };
unsigned long orig_gpr2;
unsigned int int_code;
unsigned int int_parm;
new file mode 100644
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _UAPI__ASM_BPF_PERF_EVENT_H__
+#define _UAPI__ASM_BPF_PERF_EVENT_H__
+
+#include <asm/ptrace.h>
+
+typedef user_pt_regs bpf_user_pt_regs_t;
+
+#endif /* _UAPI__ASM_BPF_PERF_EVENT_H__ */
@@ -291,6 +291,17 @@
} s390_regs;
/*
+ * The user_pt_regs structure exports the beginning of
+ * the in-kernel pt_regs structure to user space.
+ */
+typedef struct
+{
+ unsigned long args[1];
+ psw_t psw;
+ unsigned long gprs[NUM_GPRS];
+} user_pt_regs;
+
+/*
* Now for the user space program event recording (trace) definitions.
* The following structures are used only for the ptrace interface, don't
* touch or even look at it if you don't want to modify the user-space
To mitigate and correct the broken uapi for the BPF_PROG_TYPE_PERF_EVENT program type, introduce a user_pt_regs structure (similar to arm64) that exports parts from the beginnig of the pt_regs structure. The export must start with the beginning of the pt_regs structure because to correctly calculate BPF prologues for perf (regs_query_register_offset()). For BPF_PROG_TYPE_PERF_EVENT program types, the BPF program is then passed a user_pt_regs structure. Note: Depending on future changes to the s390 pt_regs structure, consider the user_pt_regs structure to be stable for a particular kernel version only. (Of course, s390 tries to ensure keep it stable as much as possible.) Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> --- arch/s390/include/asm/perf_event.h | 1 + arch/s390/include/asm/ptrace.h | 11 ++++++++--- arch/s390/include/uapi/asm/bpf_perf_event.h | 9 +++++++++ arch/s390/include/uapi/asm/ptrace.h | 11 +++++++++++ 4 files changed, 29 insertions(+), 3 deletions(-) create mode 100644 arch/s390/include/uapi/asm/bpf_perf_event.h