Re: [Qemu-devel] [PATCH v9 3/9] block: add empty account cookie type

[Alberto Garcia]

On Fri 06 Sep 2019 06:01:14 PM CEST, Anton Nefedov wrote:
> This adds some protection from accounting uninitialized cookie.
> That is, block_acct_failed/done without previous block_acct_start;
> in that case, cookie probably holds values from previous operation.
>
> (Note: it might also be uninitialized holding garbage value and there
> is still "< BLOCK_MAX_IOTYPE" assertion for that.  So
> block_acct_failed/done without previous block_acct_start should be
> used with caution.)
>
> Currently this is particularly useful in ide code where it's hard to
> keep track whether the request started accounting or not. For example,
> trim requests do the accounting separately.

Sorry if I'm understanding it wrong, but it sounds like you know that
there's a bug in the ide code (where you call block_acct_done() without
having it initialized it first), and the purpose of the this patch is to
hide the bug ?

Berto