Re: [PATCH -next] iommu/amd: fix a warning in increase_address_space

From: Jerry Snitselaar
Date: Wed Oct 16 2019 - 18:59:20 EST


On Wed Oct 16 19, Jerry Snitselaar wrote:
On Wed Oct 16 19, Qian Cai wrote:

BTW, Joerg, this line from the commit "iommu/amd: Remove domain->updated" looks
suspicious. Not sure what the purpose of it.

*updated = increase_address_space(domain, gfp) || *updated;


Looking at it again I think that isn't an issue really, it would just
not lose updated being set in a previous loop iteration, but now
I'm wondering about the loop itself. In the cases where it would return
false, how does the evaluation of the condition for the while loop
change?


I guess the mode level 6 check is really for other potential callers
increase_address_space, none exist at the moment, and the condition
of the while loop in alloc_pte should fail if the mode level is 6.