Re: [PATCH] iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE

2020-09-25 Thread Greg KH
On Fri, Sep 25, 2020 at 11:45:05AM +, Suravee Suthikulpanit wrote: > When using 128-bit interrupt-remapping table entry (IRTE) (a.k.a GA mode), > current driver disables interrupt remapping when it updates the IRTE > so that the upper and lower 64-bit values can be updated safely. > >

[PATCH] iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE

2020-09-25 Thread Suravee Suthikulpanit
When using 128-bit interrupt-remapping table entry (IRTE) (a.k.a GA mode), current driver disables interrupt remapping when it updates the IRTE so that the upper and lower 64-bit values can be updated safely. However, this creates a small window, where the interrupt could arrive and result in