Got following build fail on powerpc:
CC arch/powerpc/util/skip-callchain-idx.o
In function ‘check_return_reg’,
inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
in a region of size 64 [-Werror=stringop-overflow=]
54 | result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
In file included from /usr/include/elfutils/libdwfl.h:32,
from arch/powerpc/util/skip-callchain-idx.c:10:
/usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
| ^~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
The dwarf_frame_register args changed with [1],
Updating ops_mem accordingly.
[1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65
Cc: Mark Wielaard <[email protected]>
Cc: Sukadev Bhattiprolu <[email protected]>
Signed-off-by: Jiri Olsa <[email protected]>
---
tools/perf/arch/powerpc/util/skip-callchain-idx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
index 3018a054526a..20cd6244863b 100644
--- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c
+++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
@@ -45,7 +45,7 @@ static const Dwfl_Callbacks offline_callbacks = {
*/
static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
{
- Dwarf_Op ops_mem[2];
+ Dwarf_Op ops_mem[3];
Dwarf_Op dummy;
Dwarf_Op *ops = &dummy;
size_t nops;
--
2.31.1
Hi,
On Tue, Sep 28, 2021 at 09:52:53PM +0200, Jiri Olsa wrote:
> Got following build fail on powerpc:
>
> CC arch/powerpc/util/skip-callchain-idx.o
> In function ‘check_return_reg’,
> inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
> inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
> arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
> in a region of size 64 [-Werror=stringop-overflow=]
> 54 | result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
> arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
> In file included from /usr/include/elfutils/libdwfl.h:32,
> from arch/powerpc/util/skip-callchain-idx.c:10:
> /usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
> 1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
> | ^~~~~~~~~~~~~~~~~~~~
> cc1: all warnings being treated as errors
>
> The dwarf_frame_register args changed with [1],
> Updating ops_mem accordingly.
>
> [1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65
The warning (new with GCC11) and the fix are correct.
The code probably worked fine before because the next var on the stack
was the dummy Dwarf_Op which would have been as if the ops_mem[2] was
actually ops_mem[3] already. You don't need the dummy var now and
Dwarf_Op *ops doesn't need to be initialized (the dwarf_frame_register
will initialize it).
Note that [1] didn't change the args of the dwarf_frame_register, but
did fix a similar bug in one of the elfutils own tests (and updated
the comment on the function to hopefully be more clear).
Cheers,
Mark
> Cc: Mark Wielaard <[email protected]>
> Cc: Sukadev Bhattiprolu <[email protected]>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> tools/perf/arch/powerpc/util/skip-callchain-idx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> index 3018a054526a..20cd6244863b 100644
> --- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> +++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> @@ -45,7 +45,7 @@ static const Dwfl_Callbacks offline_callbacks = {
> */
> static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
> {
> - Dwarf_Op ops_mem[2];
> + Dwarf_Op ops_mem[3];
> Dwarf_Op dummy;
> Dwarf_Op *ops = &dummy;
> size_t nops;
> --
> 2.31.1
>
On 9/29/21 1:22 AM, Jiri Olsa wrote:
> Got following build fail on powerpc:
>
> CC arch/powerpc/util/skip-callchain-idx.o
> In function ‘check_return_reg’,
> inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
> inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
> arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
> in a region of size 64 [-Werror=stringop-overflow=]
> 54 | result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
> arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
> In file included from /usr/include/elfutils/libdwfl.h:32,
> from arch/powerpc/util/skip-callchain-idx.c:10:
> /usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
> 1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
> | ^~~~~~~~~~~~~~~~~~~~
> cc1: all warnings being treated as errors
>
> The dwarf_frame_register args changed with [1],
> Updating ops_mem accordingly.
>
> [1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65
Hi Jiri,
Thanks for the patch. I was able to reproduce this issue with gcc11 and
verified that with your change we no longer seeing this error.
Reviewed-by: Kajol Jain<[email protected]>
Tested-by: Kajol Jain<[email protected]>
Thanks,
Kajol Jain
>
> Cc: Mark Wielaard <[email protected]>
> Cc: Sukadev Bhattiprolu <[email protected]>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> tools/perf/arch/powerpc/util/skip-callchain-idx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> index 3018a054526a..20cd6244863b 100644
> --- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> +++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> @@ -45,7 +45,7 @@ static const Dwfl_Callbacks offline_callbacks = {
> */
> static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
> {
> - Dwarf_Op ops_mem[2];
> + Dwarf_Op ops_mem[3];
> Dwarf_Op dummy;
> Dwarf_Op *ops = &dummy;
> size_t nops;
>
Em Tue, Sep 28, 2021 at 10:39:05PM +0200, Mark Wielaard escreveu:
> Hi,
>
> On Tue, Sep 28, 2021 at 09:52:53PM +0200, Jiri Olsa wrote:
> > Got following build fail on powerpc:
> >
> > CC arch/powerpc/util/skip-callchain-idx.o
> > In function ‘check_return_reg’,
> > inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
> > inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
> > arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
> > in a region of size 64 [-Werror=stringop-overflow=]
> > 54 | result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
> > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
> > arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
> > In file included from /usr/include/elfutils/libdwfl.h:32,
> > from arch/powerpc/util/skip-callchain-idx.c:10:
> > /usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
> > 1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
> > | ^~~~~~~~~~~~~~~~~~~~
> > cc1: all warnings being treated as errors
> >
> > The dwarf_frame_register args changed with [1],
> > Updating ops_mem accordingly.
> >
> > [1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65
>
> The warning (new with GCC11) and the fix are correct.
I'm taking this as an Acked-by, ok?
- Arnaldo
> The code probably worked fine before because the next var on the stack
> was the dummy Dwarf_Op which would have been as if the ops_mem[2] was
> actually ops_mem[3] already. You don't need the dummy var now and
> Dwarf_Op *ops doesn't need to be initialized (the dwarf_frame_register
> will initialize it).
>
> Note that [1] didn't change the args of the dwarf_frame_register, but
> did fix a similar bug in one of the elfutils own tests (and updated
> the comment on the function to hopefully be more clear).
>
> Cheers,
>
> Mark
>
> > Cc: Mark Wielaard <[email protected]>
> > Cc: Sukadev Bhattiprolu <[email protected]>
> > Signed-off-by: Jiri Olsa <[email protected]>
> > ---
> > tools/perf/arch/powerpc/util/skip-callchain-idx.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> > index 3018a054526a..20cd6244863b 100644
> > --- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> > +++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
> > @@ -45,7 +45,7 @@ static const Dwfl_Callbacks offline_callbacks = {
> > */
> > static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
> > {
> > - Dwarf_Op ops_mem[2];
> > + Dwarf_Op ops_mem[3];
> > Dwarf_Op dummy;
> > Dwarf_Op *ops = &dummy;
> > size_t nops;
> > --
> > 2.31.1
> >
--
- Arnaldo