Re: [PATCH v2] Fix kmem failing to print task context when address is vmalloced stack

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2022/09/01 14:52, Tao Liu wrote:
> Hi Kazu,
> 
> I see 3 out of 4 patches I posted upstream have been merged, could you
> please help to merge this patch as well? Thank you very much!

This patch is waiting for Lianbo's review.
Did I miss it?

Thanks,
Kazu

> 
> Thanks,
> Tao Liu
> 
> On Mon, Aug 29, 2022 at 3:21 PM HAGIO KAZUHITO(萩尾 一仁)
> <k-hagio-ab@xxxxxxx> wrote:
>>
>> On 2022/08/25 15:42, Tao Liu wrote:
>>> When kernel enabled CONFIG_VMAP_STACK, stack can be allocated to
>>> vmalloced area. Currently crash didn't handle the case, as a result,
>>> kmem will not print the task context as expected. This patch fix the
>>> bug by checking if the address is a vmalloced stack first.
>>>
>>> Before:
>>>       crash> kmem ffffb7efce9bbe28
>>>          VMAP_AREA         VM_STRUCT                 ADDRESS RANGE                SIZE
>>>       ffff94eb9102c640  ffff94eb9102b140  ffffb7efce9b8000 - ffffb7efce9bd000    20480
>>>
>>>          PAGE         PHYSICAL      MAPPING       INDEX CNT FLAGS
>>>       ffffdd28220dc000 1883700000                0        0  1 50000000000000
>>>
>>> After:
>>>       crash> kmem ffffb7efce9bbe28
>>>        PID: 847
>>>       COMMAND: "khungtaskd"
>>>          TASK: ffff94f8038f4000  [THREAD_INFO: ffff94f8038f4000]
>>>        CPU: 72
>>>         STATE: TASK_RUNNING (PANIC)
>>>
>>>          VMAP_AREA         VM_STRUCT                 ADDRESS RANGE                SIZE
>>>       ffff94eb9102c640  ffff94eb9102b140  ffffb7efce9b8000 - ffffb7efce9bd000    20480
>>>
>>>          PAGE         PHYSICAL      MAPPING       INDEX CNT FLAGS
>>>       ffffdd28220dc000 1883700000                0        0  1 50000000000000
>>>
>>> Signed-off-by: Tao Liu <ltao@xxxxxxxxxx>
>>> ---
>>>
>>> v1 -> v2: 1) Remove goto to print task context and vmlist.
>>>             2) Update commit log to show the change.
>>
>> Thanks for the update, looks good to me.
>>
>> Acked-by: Kazuhito Hagio <k-hagio-ab@xxxxxxx>
>>
>> Thanks,
>> Kazu
>>
>>>
>>> ---
>>>    memory.c | 4 ++++
>>>    1 file changed, 4 insertions(+)
>>>
>>> diff --git a/memory.c b/memory.c
>>> index 7339f0c..9ab5781 100644
>>> --- a/memory.c
>>> +++ b/memory.c
>>> @@ -13477,6 +13477,10 @@ kmem_search(struct meminfo *mi)
>>>         *  Check for a valid mapped address.
>>>         */
>>>        if ((mi->memtype == KVADDR) && IS_VMALLOC_ADDR(mi->spec_addr)) {
>>> +             if ((task = stkptr_to_task(vaddr)) && (tc = task_to_context(task))) {
>>> +                     show_context(tc);
>>> +                     fprintf(fp, "\n");
>>> +             }
>>>                if (kvtop(NULL, mi->spec_addr, &paddr, 0)) {
>>>                        mi->flags = orig_flags | VMLIST_VERIFY;
>>>                        dump_vmlist(mi);
--
Crash-utility mailing list
Crash-utility@xxxxxxxxxx
https://listman.redhat.com/mailman/listinfo/crash-utility
Contribution Guidelines: https://github.com/crash-utility/crash/wiki




[Index of Archives]     [Fedora Development]     [Fedora Desktop]     [Fedora SELinux]     [Yosemite News]     [KDE Users]     [Fedora Tools]

 

Powered by Linux