Re: [RFC PATCH V2 4/7] x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_mask

On Tue, May 26, 2020 at 12:39 PM Andy Lutomirski wrote: > > On Mon, May 25, 2020 at 9:31 PM Lai Jiangshan > wrote: > > > > On Tue, May 26, 2020 at 12:21 PM Andy Lutomirski wrote: > > > > > > On Mon, May 25, 2020 at 6:42 PM Lai Jiangshan > > > wrote: > > > > > > > > The percpu

Re: [RFC PATCH V2 4/7] x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_mask

On Mon, May 25, 2020 at 9:31 PM Lai Jiangshan wrote: > > On Tue, May 26, 2020 at 12:21 PM Andy Lutomirski wrote: > > > > On Mon, May 25, 2020 at 6:42 PM Lai Jiangshan > > wrote: > > > > > > The percpu user_pcid_flush_mask is used for CPU entry > > > If a data breakpoint on it, it will cause an

Re: [RFC PATCH V2 4/7] x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_mask

On Tue, May 26, 2020 at 12:21 PM Andy Lutomirski wrote: > > On Mon, May 25, 2020 at 6:42 PM Lai Jiangshan wrote: > > > > The percpu user_pcid_flush_mask is used for CPU entry > > If a data breakpoint on it, it will cause an unwanted #DB. > > Protect the full cpu_tlbstate structure to be sure. >

Re: [RFC PATCH V2 4/7] x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_mask

On Mon, May 25, 2020 at 6:42 PM Lai Jiangshan wrote: > > The percpu user_pcid_flush_mask is used for CPU entry > If a data breakpoint on it, it will cause an unwanted #DB. > Protect the full cpu_tlbstate structure to be sure. > > There are some other percpu data used in CPU entry, but they are >

[RFC PATCH V2 4/7] x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_mask

The percpu user_pcid_flush_mask is used for CPU entry If a data breakpoint on it, it will cause an unwanted #DB. Protect the full cpu_tlbstate structure to be sure. There are some other percpu data used in CPU entry, but they are either in already-protected cpu_tss_rw or are safe to trigger #DB