Messages in this thread | | | Date | Fri, 4 Jan 2013 12:34:51 -0800 | Subject | Re: [PATCH v7u1 26/31] x86: Don't enable swiotlb if there is not enough ram for it | From | Yinghai Lu <> |
| |
On Fri, Jan 4, 2013 at 9:50 AM, Shuah Khan <shuahkhan@gmail.com> wrote: > > This change doesn't take into account what swiolb was when > pci_swiotlb_detect_override() is called. Instead of returning > use_swiotlb like the original code did, it returns swiotlb which could > be zero, if !enough_mem_for_swiotlb(). > > Might work fine on Intel platforms, but not on systems where the IOMMU > driver wants to enable swiotlb for some devices as in the case of AMD. > > AMD IOMMU driver enables swiotlb for devices that are not specified in > IVRs and/or not in the AMD IOMMU scope, after it successfully > initializes IOMMU. It will explicitely set switolb=1 to make sure > reserved swiotlb memory is not released. This change will break that > case.
in that case, we have to panic....
please check attached patch.
Also for those kind of systems, users must specify crashkernel_low=72M or what ever for kdump.
Thanks
Yinghai [unhandled content-type:application/octet-stream] | |