Re: loop_set_block_size: loop0 () has still dirty pages (nrpages=2)

From: Ingo Franzki
Date: Wed Jun 16 2021 - 03:22:24 EST


On 15.06.2021 10:42, Karel Zak wrote:
> On Mon, Jun 14, 2021 at 09:35:30AM +0200, Ingo Franzki wrote:
>> However, shouldn't then the losetup userspace utility implement some kind of retry logic in case of -EAGAIN ?
>> I don't see that in the source of losetup.c nor in loopdev.c in the util-linux package. There is a retry loop in create_loop() in losetup.c retrying loopcxt_setup_device() in case of EBUSY, but not in case of EAGAIN.
>>
>> And losetup also hides the original error code and just returns EXIT_FAILURE in case of a failure. So no real good chance for the script that uses losetup to catch that error situation and perform a retry itself.
>>
>> Adding Karel Zak (the maintainer of util-linux).
>>
>> @Karel Zak: How about adding EAGAIN to the condition for performing a retry?
>>
>> Something like this:
>>
>> - if (errno == EBUSY && !hasdev && ntries < 64) {
>> + if ((errno == EBUSY || errno == EAGAIN) && !hasdev && ntries < 64) {
>> xusleep(200000);
>> ntries++;
>> continue;
>> }
>
> EAGAIN sounds like the best reason to try it again :-)
>
> Committed, it will be also available in v2.37.1.

Thanks a lot for the quick resolution!

Do you by any chance know if Fedora 34 will be updated with v2.37.1?
I guess Fedora 35 will get it in any case.
>
> Karel
>
>


--
Ingo Franzki
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