Re: [Xen-devel] [PATCH RFC] x86: enable RCU based table free when PARAVIRT

2017-08-18 Thread Vitaly Kuznetsov
Juergen Gross writes: > On 17/08/17 11:20, Vitaly Kuznetsov wrote: >> On x86 software page-table walkers depend on the fact that remote TLB flush >> does an IPI: walk is performed lockless but with interrupts disabled and in >> case the pagetable is freed the freeing CPU will

Re: [Xen-devel] [PATCH RFC] x86: enable RCU based table free when PARAVIRT

2017-08-18 Thread Juergen Gross
On 17/08/17 11:20, Vitaly Kuznetsov wrote: > On x86 software page-table walkers depend on the fact that remote TLB flush > does an IPI: walk is performed lockless but with interrupts disabled and in > case the pagetable is freed the freeing CPU will get blocked as remote TLB > flush is required.

[Xen-devel] [PATCH RFC] x86: enable RCU based table free when PARAVIRT

2017-08-17 Thread Vitaly Kuznetsov
On x86 software page-table walkers depend on the fact that remote TLB flush does an IPI: walk is performed lockless but with interrupts disabled and in case the pagetable is freed the freeing CPU will get blocked as remote TLB flush is required. On other architecture which don't require an IPI to