On 16.07.2019 18:23, Andrew Cooper wrote:
> DMA-ing to the stack is considered bad practice.  In this case, if a
> timeout occurs because of a sluggish device which is processing the
> request, the completion notification will corrupt the stack of a
> subsequent deeper call tree.
> 
> Place the poll_slot in a percpu area and DMA to that instead.
> 
> Fix the declaration of saddr in struct qinval_entry, to avoid a shift by
> two.  The requirement here is that the DMA address is dword aligned,
> which is covered by poll_slot's type.
> 
> This change does not address other issues.  Correlating completions
> after a timeout with their request is a more complicated change.
> 
> Signed-off-by: Andrew Cooper <[email protected]>

Reviewed-by: Jan Beulich <[email protected]>

Must have been quite some time since v2 ...

Jan
_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xenproject.org/mailman/listinfo/xen-devel

Reply via email to