On 4/29/18 5:06 PM, Alexei Starovoitov wrote:
On Sun, Apr 29, 2018 at 05:00:23PM -0700, Yonghong Song wrote:
On 4/29/18 4:20 PM, Alexei Starovoitov wrote:
On Sun, Apr 29, 2018 at 03:06:31PM -0700, Yonghong Song wrote:
Commit d5a00528b58c ("syscalls/core, syscalls/x86: Rename
struct pt_regs-based sys_*() to __x64_sys_*()") renamed a lot
of syscall function sys_*() to __x64_sys_*().
This caused several kprobe based samples/bpf tests failing.
This patch fixed the problem by using __x64_sys_*(),
instead of sys_*(), in bpf program SEC annotations if
the target arch is __TARGET_ARCH_x86.
Fixes: d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based
sys_*() to __x64_sys_*()")
Signed-off-by: Yonghong Song <y...@fb.com>
---
samples/bpf/map_perf_test_kern.c | 32
+++++++++++++++++++++++
samples/bpf/test_current_task_under_cgroup_kern.c | 4 +++
samples/bpf/test_map_in_map_kern.c | 4 +++
samples/bpf/test_probe_write_user_kern.c | 4 +++
samples/bpf/trace_output_kern.c | 4 +++
samples/bpf/tracex2_kern.c | 4 +++
6 files changed, 52 insertions(+)
diff --git a/samples/bpf/map_perf_test_kern.c b/samples/bpf/map_perf_test_kern.c
index 2b2ffb9..79f4320 100644
--- a/samples/bpf/map_perf_test_kern.c
+++ b/samples/bpf/map_perf_test_kern.c
@@ -95,7 +95,11 @@ struct bpf_map_def SEC("maps") lru_hash_lookup_map = {
.max_entries = MAX_ENTRIES,
};
+#ifdef __TARGET_ARCH_x86
+SEC("kprobe/__x64_sys_getuid")
+#else
SEC("kprobe/sys_getuid")
+#endif
I think it would be better to hack bpf_load.c to add __x64_
automatically when it matches "sys_" in the beginning of kprobe name.
I thought this before but there a few outliers for the particular
kernel configuration I have for latest bpf-next:
drivers/video/fbdev/core/sysfillrect.c:
void sys_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
drivers/video/fbdev/core/syscopyarea.c:
void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
drivers/video/fbdev/core/sysimgblt.c:
void sys_imageblit(struct fb_info *p, const struct fb_image *image)
I am not sure whether any other outliers for other configurations or
in the future somebody could introduces a kernel function sys_ but
not a syscall.
How about trying to kprobe both ?
First __x64_sys_* and if it doesn't exist kprobe on sys_* ?
This should work. Let us do this.
