Re: [PATCH] migration: fix SEEK_CUR offset calculation in qio_channel_block_seek

[Fabiano Rosas <farosas@suse.de>]

Michael Tokarev <mjt@tls.msk.ru> writes:

> 26.03.2025 19:22, Marco Cavenati wrote:
>> The SEEK_CUR case in qio_channel_block_seek was incorrectly using the
>> 'whence' parameter instead of the 'offset' parameter when calculating the
>> new position.
>> 
>> Fixes: 65cf200a51ddc6d0a28ecceac30dc892233cddd7 ("migration: introduce a QIOChannel impl for BlockDriverState VMState")
>> 
>> Signed-off-by: Marco Cavenati <Marco.Cavenati@eurecom.fr>
>> ---
>>   migration/channel-block.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/migration/channel-block.c b/migration/channel-block.c
>> index fff8d87094..b0477f5b6d 100644
>> --- a/migration/channel-block.c
>> +++ b/migration/channel-block.c
>> @@ -123,7 +123,7 @@ qio_channel_block_seek(QIOChannel *ioc,
>>           bioc->offset = offset;
>>           break;
>>       case SEEK_CUR:
>> -        bioc->offset += whence;
>> +        bioc->offset += offset;
>>           break;
>>       case SEEK_END:
>>           error_setg(errp, "Size of VMstate region is unknown");
>
> Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
>
> This is a (trivial) bugfix, I'd say it should be in 10.0.
> Will you guys send a pullreq for the block layer, or should
> I make a single-patch pullreq from the trivial tree?

I'll take it. It's not entirely trivial as it shifts a value by 1 in
mapped-ram migration. Fortunately, it's a value that doesn't need to be
the same between migration source and destination.

Thanks

>
> Thanks,
>
> /mjt