On Thu, Jun 8, 2023 at 5:56 PM lijiang <lijiang(a)redhat.com> wrote:
On Thu, Jun 8, 2023 at 5:02 PM HAGIO KAZUHITO(萩尾 一仁)
<k-hagio-ab(a)nec.com>
wrote:
> On 2023/06/08 13:31, Lianbo Jiang wrote:
> > Crash tool will fail to load vmcore with the following error:
> >
> > #crash vmlinux /var/crash/127.0.0.1-2023-06-07-22\:03\:24/vmcore -s
> > crash: invalid structure size: note_buf
> > FILE: diskdump.c LINE: 121 FUNCTION: have_crash_notes()
> >
> > [./crash] error trace: 101859ac => 10291798 => 10291450 => 10266038
> >
> > 10266038: SIZE_verify+156
> > 10291450: have_crash_notes+308
> > 10291798: map_cpus_to_prstatus_kdump_cmprs+448
> > 101859ac: task_init+11980
> >
> > The reason is that the note_buf is not intialized before using the
> > SIZE(note_buf) in the have_crash_notes(). Let's initialize the variable
> > note_buf in the ppc64_init() to fix this issue.
>
> Thanks for the patch.
>
> Most of the architectures already have it, but some still do not have,
I don't have a 4 cpus s390x machine on hand, and am still trying to find
it.
>
> e.g. is s390x ok? It might be better to put it in task_init() because
It was initialized in the machdep_init(POST_GDB), see the following code:
...
read_in_kernel_config(IKCFG_INIT);
kernel_init();
machdep_init(POST_GDB); <---
vm_init();
machdep_init(POST_VM);
module_init();
help_init();
task_init();
vfs_init();
net_init();
dev_init();
machdep_init(POST_INIT);
...
I would suggest putting it at the end of the kernel_init(), so that the
original initialization order will basically no be changed
Sorry, It's a typo. I mean that:
I would suggest putting it at the end of the kernel_init(), so that the
original initialization order will basically not be changed, and which does
not cause additional risks.
Thanks.
Lianbo
>
> it's used there?
>
Do you mean we need to move the existing initialization(all) to the
task_init()?
>
> $ git grep 'STRUCT_SIZE_INIT(note_buf'
> arm.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> arm64.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> mips.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> mips64.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> ppc.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> riscv64.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> x86.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> x86_64.c: STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> xen_hyper.c: XEN_HYPER_STRUCT_SIZE_INIT(note_buf_t, "note_buf_t");
>
> Thanks,
> Kazu
>
> >
> > Fixes: db8c030857b4 ("diskdump/netdump: fix segmentation fault caused
> by failure of stopping CPUs")
> > Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
> > ---
> > ppc64.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/ppc64.c b/ppc64.c
> > index b95a621d8fe4..ff7f0fca3a95 100644
> > --- a/ppc64.c
> > +++ b/ppc64.c
> > @@ -695,6 +695,7 @@ ppc64_init(int when)
> > }
> >
> > ppc64_init_paca_info();
> > + STRUCT_SIZE_INIT(note_buf, "note_buf_t");
> >
> > if (!machdep->hz) {
> > machdep->hz = HZ;