Re: [PATCH] tools/perf: Fix bpf__probe to set bpf_prog_type type only if differs from the desired one
On Thu, Aug 17, 2023 at 10:35 AM Athira Rajeev
wrote:
>
>
>
> > On 07-Aug-2023, at 11:07 AM, Sachin Sant wrote:
> >
> >
> >
> >> On 07-Aug-2023, at 10:22 AM, Athira Rajeev
> >> wrote:
> >>
> >> The test "BPF prologue generation" fails as below:
> >>
> >> Writing event: p:perf_bpf_probe/func _text+10423200 f_mode=+20(%gpr3):x32
> >> offset=%gpr4:s64 orig=%gpr5:s32
> >> In map_prologue, ntevs=1
> >> mapping[0]=0
> >> libbpf: prog 'bpf_func__null_lseek': BPF program load failed: Permission
> >> denied
> >> libbpf: prog 'bpf_func__null_lseek': -- BEGIN PROG LOAD LOG --
> >> btf_vmlinux is malformed
> >> reg type unsupported for arg#0 function bpf_func__null_lseek#5
> >> 0: R1=ctx(off=0,imm=0) R10=fp0
> >> ;
> >> 0: (57) r3 &= 2
> >> R3 !read_ok
> >> processed 1 insns (limit 100) max_states_per_insn 0 total_states 0
> >> peak_states 0 mark_read 0
> >> -- END PROG LOAD LOG --
> >> libbpf: prog 'bpf_func__null_lseek': failed to load: -13
> >> libbpf: failed to load object '[bpf_prologue_test]'
> >> bpf: load objects failed: err=-13: (Permission denied)
> >> Failed to add events selected by BPF
> >>
> >> This fails occurs after this commit:
> >> commit d6e6286a12e7 ("libbpf: disassociate section handler
> >> on explicit bpf_program__set_type() call")'
> >>
> >> With this change, SEC_DEF handler libbpf which is determined
> >> initially based on program's SEC() is set to NULL. The change
> >> is made because sec_def is not valid when user sets the program
> >> type with bpf_program__set_type function. This commit also fixed
> >> bpf_prog_test_load() helper in selftests/bpf to force-set program
> >> type only if it differs from the desired one.
> >>
> >> The "bpf__probe" function in util/bpf-loader.c, also calls
> >> bpf_program__set_type to set bpf_prog_type. Add similar fix in
> >> here as well to avoid setting sec_def to NULL.
> >>
> >> Reported-by: Sachin Sant
> >> Signed-off-by: Athira Rajeev
> >> ---
> >
> > Thanks Athira for the fix.
> > With this patch applied perf BPF prologue sub test works correctly.
> >
> > 42: BPF filter :
> > 42.1: Basic BPF filtering: Ok
> > 42.2: BPF pinning : Ok
> > 42.3: BPF prologue generation : Ok
> >
> > Tested-by: Sachin Sant
> >
> > Can you please use the above mentioned id(without vnet) in the reported-by ?
> >
> > - Sachin
>
> Hi All,
>
> Looking for review comments on this patch
>
> Athira
Hi,
the patch set:
https://lore.kernel.org/lkml/20230810184853.2860737-1-irog...@google.com/
removes the affected code/test.
Thanks,
Ian
Re: [PATCH] tools/perf: Fix bpf__probe to set bpf_prog_type type only if differs from the desired one
> On 07-Aug-2023, at 11:07 AM, Sachin Sant wrote:
>
>
>
>> On 07-Aug-2023, at 10:22 AM, Athira Rajeev
>> wrote:
>>
>> The test "BPF prologue generation" fails as below:
>>
>> Writing event: p:perf_bpf_probe/func _text+10423200 f_mode=+20(%gpr3):x32
>> offset=%gpr4:s64 orig=%gpr5:s32
>> In map_prologue, ntevs=1
>> mapping[0]=0
>> libbpf: prog 'bpf_func__null_lseek': BPF program load failed: Permission
>> denied
>> libbpf: prog 'bpf_func__null_lseek': -- BEGIN PROG LOAD LOG --
>> btf_vmlinux is malformed
>> reg type unsupported for arg#0 function bpf_func__null_lseek#5
>> 0: R1=ctx(off=0,imm=0) R10=fp0
>> ;
>> 0: (57) r3 &= 2
>> R3 !read_ok
>> processed 1 insns (limit 100) max_states_per_insn 0 total_states 0
>> peak_states 0 mark_read 0
>> -- END PROG LOAD LOG --
>> libbpf: prog 'bpf_func__null_lseek': failed to load: -13
>> libbpf: failed to load object '[bpf_prologue_test]'
>> bpf: load objects failed: err=-13: (Permission denied)
>> Failed to add events selected by BPF
>>
>> This fails occurs after this commit:
>> commit d6e6286a12e7 ("libbpf: disassociate section handler
>> on explicit bpf_program__set_type() call")'
>>
>> With this change, SEC_DEF handler libbpf which is determined
>> initially based on program's SEC() is set to NULL. The change
>> is made because sec_def is not valid when user sets the program
>> type with bpf_program__set_type function. This commit also fixed
>> bpf_prog_test_load() helper in selftests/bpf to force-set program
>> type only if it differs from the desired one.
>>
>> The "bpf__probe" function in util/bpf-loader.c, also calls
>> bpf_program__set_type to set bpf_prog_type. Add similar fix in
>> here as well to avoid setting sec_def to NULL.
>>
>> Reported-by: Sachin Sant
>> Signed-off-by: Athira Rajeev
>> ---
>
> Thanks Athira for the fix.
> With this patch applied perf BPF prologue sub test works correctly.
>
> 42: BPF filter :
> 42.1: Basic BPF filtering: Ok
> 42.2: BPF pinning : Ok
> 42.3: BPF prologue generation : Ok
>
> Tested-by: Sachin Sant
>
> Can you please use the above mentioned id(without vnet) in the reported-by ?
>
> - Sachin
Hi All,
Looking for review comments on this patch
Athira
Re: [PATCH] tools/perf: Fix bpf__probe to set bpf_prog_type type only if differs from the desired one
> On 07-Aug-2023, at 10:22 AM, Athira Rajeev
> wrote:
>
> The test "BPF prologue generation" fails as below:
>
> Writing event: p:perf_bpf_probe/func _text+10423200 f_mode=+20(%gpr3):x32
> offset=%gpr4:s64 orig=%gpr5:s32
> In map_prologue, ntevs=1
> mapping[0]=0
> libbpf: prog 'bpf_func__null_lseek': BPF program load failed: Permission
> denied
> libbpf: prog 'bpf_func__null_lseek': -- BEGIN PROG LOAD LOG --
> btf_vmlinux is malformed
> reg type unsupported for arg#0 function bpf_func__null_lseek#5
> 0: R1=ctx(off=0,imm=0) R10=fp0
> ;
> 0: (57) r3 &= 2
> R3 !read_ok
> processed 1 insns (limit 100) max_states_per_insn 0 total_states 0
> peak_states 0 mark_read 0
> -- END PROG LOAD LOG --
> libbpf: prog 'bpf_func__null_lseek': failed to load: -13
> libbpf: failed to load object '[bpf_prologue_test]'
> bpf: load objects failed: err=-13: (Permission denied)
> Failed to add events selected by BPF
>
> This fails occurs after this commit:
> commit d6e6286a12e7 ("libbpf: disassociate section handler
> on explicit bpf_program__set_type() call")'
>
> With this change, SEC_DEF handler libbpf which is determined
> initially based on program's SEC() is set to NULL. The change
> is made because sec_def is not valid when user sets the program
> type with bpf_program__set_type function. This commit also fixed
> bpf_prog_test_load() helper in selftests/bpf to force-set program
> type only if it differs from the desired one.
>
> The "bpf__probe" function in util/bpf-loader.c, also calls
> bpf_program__set_type to set bpf_prog_type. Add similar fix in
> here as well to avoid setting sec_def to NULL.
>
> Reported-by: Sachin Sant
> Signed-off-by: Athira Rajeev
> ---
Thanks Athira for the fix.
With this patch applied perf BPF prologue sub test works correctly.
42: BPF filter :
42.1: Basic BPF filtering: Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
Tested-by: Sachin Sant
Can you please use the above mentioned id(without vnet) in the reported-by ?
- Sachin
