[kpatch] [issue] ERROR: trace.o: kpatch_create_mcount_sections: 2446: function 'print_trace_header' has no fentry call

[Corey Henderson]

On 9/19/2014 9:03 PM, Xie XiuQi wrote:
> Hello guys,
>
> When I create a kpatch from source directory, I got this error:
>
> $ kpatch-build -s /home/xiexiuqi/linux-3.10.0-123.6.3.el7 cmdline-string.patch -d
> ...
> sym 894, type 0, bind 1, ndx 00, name __start___trace_bprintk_fmt (SAME)
> sym 895, type 0, bind 1, ndx 00, name ring_buffer_discard_commit (SAME)
> sym 896, type 0, bind 1, ndx 00, name ring_buffer_read_page (SAME)
> lookup for print_trace_header @ 0xffffffff81115a30 len 541
> lookup for trace_flags @ 0xffffffff81939ce8 len 8
> lookup for get_total_entries.isra.20 @ 0xffffffff81111b20 len 207
> lookup for seq_print_ip_sym @ 0xffffffff8111a0f0 len 131
> lookup for trace_print_seq @ 0xffffffff81119560 len 74
> lookup for seq_print_ip_sym @ 0xffffffff8111a0f0 len 131
> lookup for trace_print_seq @ 0xffffffff81119560 len 74
> /usr/local/libexec/kpatch/create-diff-object: ERROR: trace.o: kpatch_create_mcount_sections: 2446: function 'print_trace_header' has no fentry call; unable to patch
> + rc=1
> + [[ 1 = 139 ]]
> + [[ 1 -eq 0 ]]
> + [[ 1 -eq 3 ]]
> ++ expr 2 + 1
> + ERROR=3
> + [[ 1 -eq 0 ]]
> + [[ 3 -ne 0 ]]
> + die '3 error(s) encountered'
> + [[ -z 3 error(s) encountered ]]
> + msg='3 error(s) encountered'
> + warn '3 error(s) encountered. Check /tmp/kpatch-build-1411109002.log for more details.'
> + echo 'ERROR: 3 error(s) encountered. Check /tmp/kpatch-build-1411109002.log for more details.'
> ERROR: 3 error(s) encountered. Check /tmp/kpatch-build-1411109002.log for more details.
> + exit 1
> ...
>
>
> $ cat cmdline-string.patch
> Index: src/fs/proc/cmdline.c
> ===================================================================
> --- src.orig/fs/proc/cmdline.c
> +++ src/fs/proc/cmdline.c
> @@ -5,7 +5,7 @@
>
>   static int cmdline_proc_show(struct seq_file *m, void *v)
>   {
> -	seq_printf(m, "%s\n", saved_command_line);
> +	seq_printf(m, "%s kpatch=1\n", saved_command_line);
>   	return 0;
>   }
>
> This patch 'cmdline-string.patch' just modified cmdline.c, but I got so many
> changed objects:
>
> kernel/sys.o
> kernel/module.o
> kernel/trace/trace.o
> fs/proc/cmdline.o
> drivers/base/firmware_class.o
> drivers/gpu/drm/i915/i915_gpu_error.o
> drivers/net/team/team.o
> drivers/target/target_core_configfs.o
> drivers/target/tcm_fc/tfc_conf.o
>
> I don't know why?
>
> However I build successful from .src.rpm:
> $ kpatch-build -r /home/xiexiuqi/kernel-3.10.0-123.6.3.el7.src.rpm cmdline-string.patch -d
>
> _______________________________________________
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> https://www.redhat.com/mailman/listinfo/kpatch
>


Hi,

Try rerunning the command with "-t vmlinux" at the end.

I'm assuming you're trying this from an EL7 system?

Thanks,