2018-10-09 10:35:22

by Roger Pau Monne

Subject: [PATCH] xen/pvh: increase early stack size

While booting on an AMD EPYC box the stack canary would detect stack
overflows when using the current PVH early stack size (256). Switch to
using the value defined by BOOT_STACK_SIZE, which prevents the stack
overflow.

Signed-off-by: Roger Pau Monné <[email protected]>
---
Cc: Boris Ostrovsky <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: [email protected]
---
arch/x86/xen/xen-pvh.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S
index ca2d3b2bf2af..58722a052f9c 100644
--- a/arch/x86/xen/xen-pvh.S
+++ b/arch/x86/xen/xen-pvh.S
@@ -181,7 +181,7 @@ canary:
.fill 48, 1, 0

early_stack:
- .fill 256, 1, 0
+ .fill BOOT_STACK_SIZE, 1, 0
early_stack_end:

ELFNOTE(Xen, XEN_ELFNOTE_PHYS32_ENTRY,
--
2.19.0

2018-10-09 11:03:00

by Jürgen Groß

Subject: Re: [PATCH] xen/pvh: increase early stack size

On 09/10/2018 12:32, Roger Pau Monne wrote:
> While booting on an AMD EPYC box the stack canary would detect stack
> overflows when using the current PVH early stack size (256). Switch to
> using the value defined by BOOT_STACK_SIZE, which prevents the stack
> overflow.
>
> Signed-off-by: Roger Pau Monné <[email protected]>

Reviewed-by: Juergen Gross <[email protected]>

I'll add a "Cc: stable" when committing.


Juergen

2018-10-10 08:05:13

by Jürgen Groß

Subject: Re: [PATCH] xen/pvh: increase early stack size

On 09/10/2018 12:32, Roger Pau Monne wrote:
> While booting on an AMD EPYC box the stack canary would detect stack
> overflows when using the current PVH early stack size (256). Switch to
> using the value defined by BOOT_STACK_SIZE, which prevents the stack
> overflow.
>
> Signed-off-by: Roger Pau Monné <[email protected]>

Committed to xen.tip for-linus-4.20


Juergen