2023-04-12 20:35:40

by Pankaj Raghav

[permalink] [raw]
Subject: [PATCH v2] scripts/gdb: use mem instead of core_layout to get the module address

commit ac3b43283923 ("module: replace module_layout with module_memory")
changed the struct module data structure from module_layout to
module_memory. The core_layout member which is used while loading
modules are not available anymore leading to the following error while
running gdb:

(gdb) lx-symbols
loading vmlinux
Python Exception <class 'gdb.error'>: There is no member named core_layout.
Error occurred in Python: There is no member named core_layout.

Replace core_layout with its new counterpart mem[MOD_TEXT].

Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
Signed-off-by: Pankaj Raghav <[email protected]>
---
scripts/gdb/linux/constants.py.in | 3 +++
scripts/gdb/linux/modules.py | 4 ++--
scripts/gdb/linux/symbols.py | 4 ++--
3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
index 36fd2b145853..471300ba176c 100644
--- a/scripts/gdb/linux/constants.py.in
+++ b/scripts/gdb/linux/constants.py.in
@@ -62,6 +62,9 @@ LX_GDBPARSED(hrtimer_resolution)
LX_GDBPARSED(IRQD_LEVEL)
LX_GDBPARSED(IRQ_HIDDEN)

+/* linux/module.h */
+LX_GDBPARSED(MOD_TEXT)
+
/* linux/mount.h */
LX_VALUE(MNT_NOSUID)
LX_VALUE(MNT_NODEV)
diff --git a/scripts/gdb/linux/modules.py b/scripts/gdb/linux/modules.py
index 441b23239896..261f28640f4c 100644
--- a/scripts/gdb/linux/modules.py
+++ b/scripts/gdb/linux/modules.py
@@ -13,7 +13,7 @@

import gdb

-from linux import cpus, utils, lists
+from linux import cpus, utils, lists, constants


module_type = utils.CachedType("struct module")
@@ -73,7 +73,7 @@ class LxLsmod(gdb.Command):
" " if utils.get_long_type().sizeof == 8 else ""))

for module in module_list():
- layout = module['core_layout']
+ layout = module['mem'][constants.LX_MOD_TEXT]
gdb.write("{address} {name:<19} {size:>8} {ref}".format(
address=str(layout['base']).split()[0],
name=module['name'].string(),
diff --git a/scripts/gdb/linux/symbols.py b/scripts/gdb/linux/symbols.py
index dc07b6d12e30..fdad3f32c747 100644
--- a/scripts/gdb/linux/symbols.py
+++ b/scripts/gdb/linux/symbols.py
@@ -15,7 +15,7 @@ import gdb
import os
import re

-from linux import modules, utils
+from linux import modules, utils, constants


if hasattr(gdb, 'Breakpoint'):
@@ -109,7 +109,7 @@ lx-symbols command."""

def load_module_symbols(self, module):
module_name = module['name'].string()
- module_addr = str(module['core_layout']['base']).split()[0]
+ module_addr = str(module['mem'][constants.LX_MOD_TEXT]['base']).split()[0]

module_file = self._get_module_file(module_name)
if not module_file and not self.module_files_updated:
--
2.39.2


2023-04-13 01:12:03

by Luis Chamberlain

[permalink] [raw]
Subject: Re: [PATCH v2] scripts/gdb: use mem instead of core_layout to get the module address

On Wed, Apr 12, 2023 at 10:25:18PM +0200, Pankaj Raghav wrote:
> commit ac3b43283923 ("module: replace module_layout with module_memory")
> changed the struct module data structure from module_layout to
> module_memory. The core_layout member which is used while loading
> modules are not available anymore leading to the following error while
> running gdb:
>
> (gdb) lx-symbols
> loading vmlinux
> Python Exception <class 'gdb.error'>: There is no member named core_layout.
> Error occurred in Python: There is no member named core_layout.
>
> Replace core_layout with its new counterpart mem[MOD_TEXT].
>
> Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
> Signed-off-by: Pankaj Raghav <[email protected]>
> ---
> scripts/gdb/linux/constants.py.in | 3 +++
> scripts/gdb/linux/modules.py | 4 ++--
> scripts/gdb/linux/symbols.py | 4 ++--
> 3 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
> index 36fd2b145853..471300ba176c 100644
> --- a/scripts/gdb/linux/constants.py.in
> +++ b/scripts/gdb/linux/constants.py.in
> @@ -62,6 +62,9 @@ LX_GDBPARSED(hrtimer_resolution)
> LX_GDBPARSED(IRQD_LEVEL)
> LX_GDBPARSED(IRQ_HIDDEN)
>
> +/* linux/module.h */
> +LX_GDBPARSED(MOD_TEXT)

Should we just fill in the rest of the other sections too while at it?

Luis

2023-04-13 07:45:54

by Pankaj Raghav

[permalink] [raw]
Subject: Re: [PATCH v2] scripts/gdb: use mem instead of core_layout to get the module address

On 2023-04-13 02:53, Luis Chamberlain wrote:
> On Wed, Apr 12, 2023 at 10:25:18PM +0200, Pankaj Raghav wrote:
>> commit ac3b43283923 ("module: replace module_layout with module_memory")
>> changed the struct module data structure from module_layout to
>> module_memory. The core_layout member which is used while loading
>> modules are not available anymore leading to the following error while
>> running gdb:
>>
>> (gdb) lx-symbols
>> loading vmlinux
>> Python Exception <class 'gdb.error'>: There is no member named core_layout.
>> Error occurred in Python: There is no member named core_layout.
>>
>> Replace core_layout with its new counterpart mem[MOD_TEXT].
>>
>> Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
>> Signed-off-by: Pankaj Raghav <[email protected]>
>> ---
>> scripts/gdb/linux/constants.py.in | 3 +++
>> scripts/gdb/linux/modules.py | 4 ++--
>> scripts/gdb/linux/symbols.py | 4 ++--
>> 3 files changed, 7 insertions(+), 4 deletions(-)
>>
>> diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
>> index 36fd2b145853..471300ba176c 100644
>> --- a/scripts/gdb/linux/constants.py.in
>> +++ b/scripts/gdb/linux/constants.py.in
>> @@ -62,6 +62,9 @@ LX_GDBPARSED(hrtimer_resolution)
>> LX_GDBPARSED(IRQD_LEVEL)
>> LX_GDBPARSED(IRQ_HIDDEN)
>>
>> +/* linux/module.h */
>> +LX_GDBPARSED(MOD_TEXT)
>
> Should we just fill in the rest of the other sections too while at it?
>

I don't see them used in the scripts. Maybe we can add them when needed?

> Luis

2023-04-13 13:53:12

by Kieran Bingham

[permalink] [raw]
Subject: Re: [PATCH v2] scripts/gdb: use mem instead of core_layout to get the module address

Quoting Pankaj Raghav (2023-04-13 08:44:38)
> On 2023-04-13 02:53, Luis Chamberlain wrote:
> > On Wed, Apr 12, 2023 at 10:25:18PM +0200, Pankaj Raghav wrote:
> >> commit ac3b43283923 ("module: replace module_layout with module_memory")
> >> changed the struct module data structure from module_layout to
> >> module_memory. The core_layout member which is used while loading
> >> modules are not available anymore leading to the following error while
> >> running gdb:
> >>
> >> (gdb) lx-symbols
> >> loading vmlinux
> >> Python Exception <class 'gdb.error'>: There is no member named core_layout.
> >> Error occurred in Python: There is no member named core_layout.
> >>
> >> Replace core_layout with its new counterpart mem[MOD_TEXT].
> >>
> >> Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
> >> Signed-off-by: Pankaj Raghav <[email protected]>
> >> ---
> >> scripts/gdb/linux/constants.py.in | 3 +++
> >> scripts/gdb/linux/modules.py | 4 ++--
> >> scripts/gdb/linux/symbols.py | 4 ++--
> >> 3 files changed, 7 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
> >> index 36fd2b145853..471300ba176c 100644
> >> --- a/scripts/gdb/linux/constants.py.in
> >> +++ b/scripts/gdb/linux/constants.py.in
> >> @@ -62,6 +62,9 @@ LX_GDBPARSED(hrtimer_resolution)
> >> LX_GDBPARSED(IRQD_LEVEL)
> >> LX_GDBPARSED(IRQ_HIDDEN)
> >>
> >> +/* linux/module.h */
> >> +LX_GDBPARSED(MOD_TEXT)
> >
> > Should we just fill in the rest of the other sections too while at it?
> >
>
> I don't see them used in the scripts. Maybe we can add them when needed?

I think there's a runtime-cost to getting these constants, as we
interogate GDB to get the values.

Because of that, I think values should only be added when required,
unless the python code is only lazy-evaluating these.

--
Kieran

2023-04-13 21:13:11

by Luis Chamberlain

[permalink] [raw]
Subject: Re: [PATCH v2] scripts/gdb: use mem instead of core_layout to get the module address

On Thu, Apr 13, 2023 at 02:47:30PM +0100, Kieran Bingham wrote:
> Quoting Pankaj Raghav (2023-04-13 08:44:38)
> > On 2023-04-13 02:53, Luis Chamberlain wrote:
> > > On Wed, Apr 12, 2023 at 10:25:18PM +0200, Pankaj Raghav wrote:
> > >> commit ac3b43283923 ("module: replace module_layout with module_memory")
> > >> changed the struct module data structure from module_layout to
> > >> module_memory. The core_layout member which is used while loading
> > >> modules are not available anymore leading to the following error while
> > >> running gdb:
> > >>
> > >> (gdb) lx-symbols
> > >> loading vmlinux
> > >> Python Exception <class 'gdb.error'>: There is no member named core_layout.
> > >> Error occurred in Python: There is no member named core_layout.
> > >>
> > >> Replace core_layout with its new counterpart mem[MOD_TEXT].
> > >>
> > >> Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
> > >> Signed-off-by: Pankaj Raghav <[email protected]>
> > >> ---
> > >> scripts/gdb/linux/constants.py.in | 3 +++
> > >> scripts/gdb/linux/modules.py | 4 ++--
> > >> scripts/gdb/linux/symbols.py | 4 ++--
> > >> 3 files changed, 7 insertions(+), 4 deletions(-)
> > >>
> > >> diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
> > >> index 36fd2b145853..471300ba176c 100644
> > >> --- a/scripts/gdb/linux/constants.py.in
> > >> +++ b/scripts/gdb/linux/constants.py.in
> > >> @@ -62,6 +62,9 @@ LX_GDBPARSED(hrtimer_resolution)
> > >> LX_GDBPARSED(IRQD_LEVEL)
> > >> LX_GDBPARSED(IRQ_HIDDEN)
> > >>
> > >> +/* linux/module.h */
> > >> +LX_GDBPARSED(MOD_TEXT)
> > >
> > > Should we just fill in the rest of the other sections too while at it?
> > >
> >
> > I don't see them used in the scripts. Maybe we can add them when needed?
>
> I think there's a runtime-cost to getting these constants, as we
> interogate GDB to get the values.
>
> Because of that, I think values should only be added when required,
> unless the python code is only lazy-evaluating these.

OK thanks, applied and pushed to modules-next.

Luis