Re: [Crash-utility] [PATCH] Fix for the invalid linux_banner pointer issue
On 2022/09/16 15:00, Lianbo Jiang wrote:
Currently, crash may fail with the following error:
# ./crash vmlinux /var/crash/127.0.0.1-2022-09-15-09:31:55/vmcore -s
WARNING: invalid linux_banner pointer: 65762078756e694c
crash: vmlinux and /var/crash/127.0.0.1-2022-09-15-09:31:55/vmcore do not match!
The reason is that the type of symbols in the data segment may be
defined as 'D' or 'd'. The crash only handled the type 'D', but
it
didn't deal with the type 'd'. For example:
# nm vmlinux |grep linux_banner
ffffffff827cfa80 d linux_banner
Let's add the type 'd' recognition to solve such issue.
Thank you for the fix, the patch diff looks good.
I've searched for a vmlinux that its symbol type is 'd', but not found.
Do you know what makes it 'd'? It would be better to add the cause to
the commit log, for future reference.
Thanks,
Kazu
>
> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
> ---
> kernel.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel.c b/kernel.c
> index a521ef30cdb0..aa030e8097ea 100644
> --- a/kernel.c
> +++ b/kernel.c
> @@ -1060,7 +1060,7 @@ verify_version(void)
> if (!(sp = symbol_search("linux_banner")))
> error(FATAL, "linux_banner symbol does not exist?\n");
> else if ((sp->type == 'R') || (sp->type == 'r') ||
> - (THIS_KERNEL_VERSION >= LINUX(2,6,11) && sp->type == 'D')
||
> + (THIS_KERNEL_VERSION >= LINUX(2,6,11) && (sp->type == 'D' ||
sp->type == 'd')) ||
> (machine_type("ARM") && sp->type == 'T') ||
> (machine_type("ARM64")))
> linux_banner = symbol_value("linux_banner");