[CRIU] [PATCH] parasite: don't use a process stack to unmap a parasite blob

[Andrey Vagin]

On Thu, Aug 18, 2016 at 12:31 AM, Mike Rapoport <mike.rapoport at gmail.com> wrote:
> On Thu, Aug 18, 2016 at 9:37 AM, Andrei Vagin <avagin at openvz.org> wrote:
>> From: Andrei Vagin <avagin at virtuozzo.com>
>>
>> Process private memory was dumped at this moment, but a memory
>> tracker isn't reseted, so we can't use a process memory here.
>>
>> https://github.com/xemul/criu/issues/203
>>
>> Cc: Eugene Batalov <eabatalov89 at gmail.com>
>> Cc: Fyodor Bocharov <fbocharov at yandex.ru>
>> Cc: Mike Rapoport <rppt at linux.vnet.ibm.com>
>> Fixes: 101e3ba49d08 ("mem: reset SOFT_DIRTY bits after dumping of all vmas in the process")
>> Signed-off-by: Andrei Vagin <avagin at virtuozzo.com>
>> ---
>>  criu/parasite-syscall.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/criu/parasite-syscall.c b/criu/parasite-syscall.c
>> index 79d04a7..18923a5 100644
>> --- a/criu/parasite-syscall.c
>> +++ b/criu/parasite-syscall.c
>> @@ -1216,7 +1216,7 @@ int parasite_unmap(struct parasite_ctl *ctl, unsigned long addr)
>>         pid_t pid = ctl->pid.real;
>>         int ret = -1;
>>
>> -       ret = parasite_run(pid, PTRACE_SYSCALL, addr, NULL, &regs, &ctl->orig);
>> +       ret = parasite_run(pid, PTRACE_SYSCALL, addr, ctl->rstack, &regs, &ctl->orig);
>
> Just curious, why parasite would use dumpee stack?

parasite_run() is used to map a parasite blob with a parasite stack

> Wouldn't it make sense to always run with ctl->rstack?
>
>>         if (ret)
>>                 goto err;
>>
>> --
>> 2.7.4
>>
>> _______________________________________________
>> CRIU mailing list
>> CRIU at openvz.org
>> https://lists.openvz.org/mailman/listinfo/criu
>
>
>
> --
> Sincerely yours,
> Mike.