Re: [patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-09 Thread Andy Lutomirski
On Sat, May 9, 2020 at 2:23 AM Lai Jiangshan wrote: > > On Tue, May 5, 2020 at 10:15 PM Thomas Gleixner wrote: > > > > From: Andy Lutomirski > > > > A data breakpoint near the top of an IST stack will cause unresoverable > > recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. >

Re: [patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-09 Thread Lai Jiangshan
On Tue, May 5, 2020 at 10:15 PM Thomas Gleixner wrote: > > From: Andy Lutomirski > > A data breakpoint near the top of an IST stack will cause unresoverable > recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. > Prevent either of these from happening. > What happen when a data

Re: [patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-09 Thread Lai Jiangshan
On Tue, May 5, 2020 at 10:15 PM Thomas Gleixner wrote: > > From: Andy Lutomirski > > A data breakpoint near the top of an IST stack will cause unresoverable > recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. > Prevent either of these from happening. > > Co-developed-by: Peter

Re: [patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-06 Thread Alexandre Chartre
On 5/5/20 3:16 PM, Thomas Gleixner wrote: From: Andy Lutomirski A data breakpoint near the top of an IST stack will cause unresoverable typo: unresoverable -> unrecoverable recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. Prevent either of these from happening.

Re: [patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-06 Thread Borislav Petkov
On Tue, May 05, 2020 at 03:16:04PM +0200, Thomas Gleixner wrote: > From: Andy Lutomirski > > A data breakpoint near the top of an IST stack will cause unresoverable unrecoverable > recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. "terrifying" huh? Colorful. :) > Prevent

[patch V4 part 1 02/36] x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area

2020-05-05 Thread Thomas Gleixner
From: Andy Lutomirski A data breakpoint near the top of an IST stack will cause unresoverable recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying. Prevent either of these from happening. Co-developed-by: Peter Zijlstra Signed-off-by: Andy Lutomirski Signed-off-by: Peter