2020-04-22 14:50:33

by Jiaxun Yang

Subject: [PATCH] MIPS: Clear XContext at boot time

XContext might be dirty at boot time. We need to clear it
to ensure early stackframe is safe.

Signed-off-by: Jiaxun Yang <[email protected]>
---
arch/mips/kernel/head.S | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 351d40fe0859..3b02ffe46304 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -132,6 +132,9 @@ dtb_found:
#endif

MTC0 zero, CP0_CONTEXT # clear context register
+#ifdef CONFIG_64BIT
+ MTC0 zero, CP0_XCONTEXT
+#endif
PTR_LA $28, init_thread_union
/* Set the SP after an empty pt_regs. */
PTR_LI sp, _THREAD_SIZE - 32 - PT_SIZE
--
2.26.0.rc2

2020-04-24 21:48:10

by Thomas Bogendoerfer

Subject: Re: [PATCH] MIPS: Clear XContext at boot time

On Wed, Apr 22, 2020 at 10:45:34PM +0800, Jiaxun Yang wrote:
> XContext might be dirty at boot time. We need to clear it
> to ensure early stackframe is safe.
>
> Signed-off-by: Jiaxun Yang <[email protected]>
> ---
> arch/mips/kernel/head.S | 3 +++
> 1 file changed, 3 insertions(+)
>

applied to mips-next.

Thomas.

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