| Message ID | 56C446F8.3050906@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Feb 17, 2016 at 10:10:00AM +0000, James Morse wrote: > On 17/02/16 09:15, Andrey Ryabinin wrote: > > On 02/16/2016 07:42 PM, Mark Rutland wrote: > >> On Tue, Feb 16, 2016 at 06:36:36PM +0300, Andrey Ryabinin wrote: > >>> You are right. > >>> So we should write 'shadow_start' instead of 'i'. > >> > >> FWIW with the below patch I don't see any "screwed shadow mapping" > >> warnings on my board, and still later see a tonne of KASAN splats in the > >> scheduler. > >> > > > > It is possible that I missed something, but I think it means that shadow is alright. > > > > I wonder whether this happens on 4.4. If not, than something in 4.5-rc1 caused this, and the obvious suspect > > here is irq stack. > > This quick hack will prevent ever switching to the irq stack: > > ---------------------------%<--------------------------- > diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S > index 1f7f5a2b61bf..83ae736429b6 100644 > --- a/arch/arm64/kernel/entry.S > +++ b/arch/arm64/kernel/entry.S > @@ -188,7 +188,7 @@ alternative_endif > */ > and x25, x19, #~(THREAD_SIZE - 1) > cmp x25, tsk > - b.ne 9998f > + b 9998f > > this_cpu_ptr irq_stack, x25, x26 > mov x26, #IRQ_STACK_START_SP Thanks James. I'll give it a try.
On Wed, Feb 17, 2016 at 10:19:41AM +0000, Catalin Marinas wrote: > On Wed, Feb 17, 2016 at 10:10:00AM +0000, James Morse wrote: > > On 17/02/16 09:15, Andrey Ryabinin wrote: > > > On 02/16/2016 07:42 PM, Mark Rutland wrote: > > >> On Tue, Feb 16, 2016 at 06:36:36PM +0300, Andrey Ryabinin wrote: > > >>> You are right. > > >>> So we should write 'shadow_start' instead of 'i'. > > >> > > >> FWIW with the below patch I don't see any "screwed shadow mapping" > > >> warnings on my board, and still later see a tonne of KASAN splats in the > > >> scheduler. > > >> > > > > > > It is possible that I missed something, but I think it means that shadow is alright. > > > > > > I wonder whether this happens on 4.4. If not, than something in 4.5-rc1 caused this, and the obvious suspect > > > here is irq stack. > > > > This quick hack will prevent ever switching to the irq stack: > > > > ---------------------------%<--------------------------- > > diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S > > index 1f7f5a2b61bf..83ae736429b6 100644 > > --- a/arch/arm64/kernel/entry.S > > +++ b/arch/arm64/kernel/entry.S > > @@ -188,7 +188,7 @@ alternative_endif > > */ > > and x25, x19, #~(THREAD_SIZE - 1) > > cmp x25, tsk > > - b.ne 9998f > > + b 9998f > > > > this_cpu_ptr irq_stack, x25, x26 > > mov x26, #IRQ_STACK_START_SP > > Thanks James. I'll give it a try. And it didn't make any difference (on top of 4.5-rc1), still the same KASAN warnings.
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 1f7f5a2b61bf..83ae736429b6 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -188,7 +188,7 @@ alternative_endif */ and x25, x19, #~(THREAD_SIZE - 1) cmp x25, tsk - b.ne 9998f + b 9998f this_cpu_ptr irq_stack, x25, x26 mov x26, #IRQ_STACK_START_SP