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SubjectRe: [PATCH v2] mm: hwpoison: coredump: support recovery from dump_user_range()
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On 2023/4/28 0:45, Luck, Tony wrote:
>>> But in the core dump case there is no return to user. The process is being
>>> terminated by the signal that leads to this core dump. So even though you
>>> may consider the page being accessed to be a "user" page, you can't fix
>>> it by queueing work to run on return to user.
>>
>> For coredump,the task work will be called too, see following code,
>>
>> get_signal
>> sig_kernel_coredump
>> elf_core_dump
>> dump_user_range
>> _copy_from_iter // with MC-safe copy, return without panic
>> do_group_exit(ksig->info.si_signo);
>> do_exit
>> exit_task_work
>> task_work_run
>> kill_me_never
>> memory_failure
>>
>
> Nice. I didn't realize that the exit code path would clear any pending task_work() requests.
> But it makes sense that this happens. Thanks for filling a gap in my knowledge.
>
Yep, we could be benefit from it to unify memory failure handling :)

> -Tony

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