vmlinux-gdb unable to parse_and_eval("hrtimer_resolution") on mainline

vmlinux-gdb unable to parse_and_eval("hrtimer_resolution") on mainline

[aftermath digital]

Hi,

I've tested the below on both linux-6.5.7 and mainline linux-6.6-rc6,
both of which seem to have the same issue.

GDB 13.2 isn't able to load vmlinux-gdb.py as it throws the following:

Traceback (most recent call last):
  File "/home/user/debug_kernel/linux-6.6-rc6/vmlinux-gdb.py", line
25, in <module>
    import linux.constants
  File "/home/user/debug_kernel/linux-6.6-rc6/scripts/gdb/linux/constants.py",
line 11, in <module>
    LX_hrtimer_resolution = gdb.parse_and_eval("hrtimer_resolution")
gdb.error: 'hrtimer_resolution' has unknown type; cast it to its declared type

I've built-linux like so:

make defconfig
scripts/config --disable SYSTEM_TRUSTED_KEYS
scripts/config --disable SYSTEM_REVOCATION_KEYS
scripts/config --set-str SYSTEM_TRUSTED_KEYS ""
scripts/config -e CONFIG_DEBUG_INFO -e CONFIG_GDB_SCRIPTS -e
CONFIG_FRAME_POINTER
make -j$(nproc)
make scripts_gdb

$ gcc --version
gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
$ gdb --version
GNU gdb (GDB) 13.2

This is my first time submitting a bug to the LK mailing list, please
let me know if this format is not correct or if you need more
information.

Thanks.

Re: vmlinux-gdb unable to parse_and_eval("hrtimer_resolution") on mainline

[Greg KH]

On Wed, Oct 18, 2023 at 08:57:47PM +0100, aftermath digital wrote:
> Hi,
> 
> I've tested the below on both linux-6.5.7 and mainline linux-6.6-rc6,
> both of which seem to have the same issue.
> 
> GDB 13.2 isn't able to load vmlinux-gdb.py as it throws the following:
> 
> Traceback (most recent call last):
>   File "/home/user/debug_kernel/linux-6.6-rc6/vmlinux-gdb.py", line
> 25, in <module>
>     import linux.constants
>   File "/home/user/debug_kernel/linux-6.6-rc6/scripts/gdb/linux/constants.py",
> line 11, in <module>
>     LX_hrtimer_resolution = gdb.parse_and_eval("hrtimer_resolution")
> gdb.error: 'hrtimer_resolution' has unknown type; cast it to its declared type
> 
> I've built-linux like so:
> 
> make defconfig
> scripts/config --disable SYSTEM_TRUSTED_KEYS
> scripts/config --disable SYSTEM_REVOCATION_KEYS
> scripts/config --set-str SYSTEM_TRUSTED_KEYS ""
> scripts/config -e CONFIG_DEBUG_INFO -e CONFIG_GDB_SCRIPTS -e
> CONFIG_FRAME_POINTER
> make -j$(nproc)
> make scripts_gdb
> 
> $ gcc --version
> gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
> $ gdb --version
> GNU gdb (GDB) 13.2
> 
> This is my first time submitting a bug to the LK mailing list, please
> let me know if this format is not correct or if you need more
> information.

Has this ever worked with any kernel version you have tried?  If so,
what was the last good version?  Can you run 'git bisect' to find the
offending commit?

thanks,

greg k-h

Re: vmlinux-gdb unable to parse_and_eval("hrtimer_resolution") on mainline

[Jan Kiszka]

On 18.10.23 21:57, aftermath digital wrote:
> Hi,
> 
> I've tested the below on both linux-6.5.7 and mainline linux-6.6-rc6,
> both of which seem to have the same issue.
> 
> GDB 13.2 isn't able to load vmlinux-gdb.py as it throws the following:
> 
> Traceback (most recent call last):
>   File "/home/user/debug_kernel/linux-6.6-rc6/vmlinux-gdb.py", line
> 25, in <module>
>     import linux.constants
>   File "/home/user/debug_kernel/linux-6.6-rc6/scripts/gdb/linux/constants.py",
> line 11, in <module>
>     LX_hrtimer_resolution = gdb.parse_and_eval("hrtimer_resolution")
> gdb.error: 'hrtimer_resolution' has unknown type; cast it to its declared type
> 
> I've built-linux like so:
> 
> make defconfig
> scripts/config --disable SYSTEM_TRUSTED_KEYS
> scripts/config --disable SYSTEM_REVOCATION_KEYS
> scripts/config --set-str SYSTEM_TRUSTED_KEYS ""
> scripts/config -e CONFIG_DEBUG_INFO -e CONFIG_GDB_SCRIPTS -e
> CONFIG_FRAME_POINTER

I happen to run into this myself recently while upgrading a .config:
CONFIG_DEBUG_INFO is now selected by DEBUG_INFO_DWARF*. I've then turned
on DEBUG_INFO_DWARF5, and things worked again.

> make -j$(nproc)
> make scripts_gdb
> 
> $ gcc --version
> gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
> $ gdb --version
> GNU gdb (GDB) 13.2
> 
> This is my first time submitting a bug to the LK mailing list, please
> let me know if this format is not correct or if you need more
> information.
> 

Format is fine, just general linux-kernel@vger... reaches a broader
audience and is more appropriate for such a question.

Jan

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