Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-08 Thread Thomas Gleixner
On Mon, 8 Apr 2019, Thomas Gleixner wrote: > On Mon, 8 Apr 2019, Andy Lutomirski wrote: > > On Sun, Apr 7, 2019 at 11:46 PM Thomas Gleixner wrote: > > > > > > On Sun, 7 Apr 2019, Andy Lutomirski wrote: > > > > On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner > > > > wrote: > > > > > Actually we h

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-08 Thread Thomas Gleixner
On Mon, 8 Apr 2019, Andy Lutomirski wrote: > On Sun, Apr 7, 2019 at 11:46 PM Thomas Gleixner wrote: > > > > On Sun, 7 Apr 2019, Andy Lutomirski wrote: > > > On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner wrote: > > > > Actually we have: save_stack_trace() > > > > > > > > > > Like I did here: > >

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-08 Thread Josh Poimboeuf
On Mon, Apr 08, 2019 at 09:18:00AM -0700, Andy Lutomirski wrote: > On Sun, Apr 7, 2019 at 11:46 PM Thomas Gleixner wrote: > > > > On Sun, 7 Apr 2019, Andy Lutomirski wrote: > > > On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner wrote: > > > > Actually we have: save_stack_trace() > > > > > > > > > >

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-08 Thread Andy Lutomirski
On Sun, Apr 7, 2019 at 11:46 PM Thomas Gleixner wrote: > > On Sun, 7 Apr 2019, Andy Lutomirski wrote: > > On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner wrote: > > > Actually we have: save_stack_trace() > > > > > > > Like I did here: > > > > https://git.kernel.org/pub/scm/linux/kernel/git/luto/li

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Thomas Gleixner
On Sun, 7 Apr 2019, Andy Lutomirski wrote: > On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner wrote: > > Actually we have: save_stack_trace() > > > > Like I did here: > > https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git/log/?h=WIP.x86/stackguards Kinda, but what that code wants is t

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Andy Lutomirski
On Sun, Apr 7, 2019 at 3:44 PM Thomas Gleixner wrote: > > On Sat, 6 Apr 2019, Andy Lutomirski wrote: > > On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > > > > > > From: Andy Lutomirski > > > > > > The IRQ stack lives in percpu space, so an IRQ handler that overflows it > > > will overwri

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Thomas Gleixner
On Sat, 6 Apr 2019, Andy Lutomirski wrote: > On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > > > > From: Andy Lutomirski > > > > The IRQ stack lives in percpu space, so an IRQ handler that overflows it > > will overwrite other data structures. > > > > Use vmap() to remap the IRQ stack so

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Andy Lutomirski
> On Apr 7, 2019, at 2:34 AM, Thomas Gleixner wrote: > > On Sun, 7 Apr 2019, Andy Lutomirski wrote: >>> On Apr 6, 2019, at 11:08 PM, Thomas Gleixner wrote: >>> > On Sat, 6 Apr 2019, Andy Lutomirski wrote: > On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > > From: Andy

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Thomas Gleixner
On Sun, 7 Apr 2019, Andy Lutomirski wrote: > > On Apr 6, 2019, at 11:08 PM, Thomas Gleixner wrote: > > > >> On Sat, 6 Apr 2019, Andy Lutomirski wrote: > >>> On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > >>> > >>> From: Andy Lutomirski > >>> > >>> The IRQ stack lives in percpu space,

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-07 Thread Andy Lutomirski
> On Apr 6, 2019, at 11:08 PM, Thomas Gleixner wrote: > >> On Sat, 6 Apr 2019, Andy Lutomirski wrote: >>> On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: >>> >>> From: Andy Lutomirski >>> >>> The IRQ stack lives in percpu space, so an IRQ handler that overflows it >>> will overwrite

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-06 Thread Thomas Gleixner
On Sat, 6 Apr 2019, Andy Lutomirski wrote: > On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > > > > From: Andy Lutomirski > > > > The IRQ stack lives in percpu space, so an IRQ handler that overflows it > > will overwrite other data structures. > > > > Use vmap() to remap the IRQ stack so

Re: [patch V2 28/29] x86/irq/64: Remap the IRQ stack with guard pages

2019-04-06 Thread Andy Lutomirski
On Fri, Apr 5, 2019 at 8:11 AM Thomas Gleixner wrote: > > From: Andy Lutomirski > > The IRQ stack lives in percpu space, so an IRQ handler that overflows it > will overwrite other data structures. > > Use vmap() to remap the IRQ stack so that it will have the usual guard > pages that vmap/vmalloc