arm64: hyp-stub: Forbid kprobing of the hyp-stub
authorJames Morse <james.morse@arm.com>
Thu, 24 Jan 2019 16:32:56 +0000 (16:32 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 Feb 2019 16:31:35 +0000 (17:31 +0100)
commit 8fac5cbdfe0f01254d9d265c6aa1a95f94f58595 upstream.

The hyp-stub is loaded by the kernel's early startup code at EL2
during boot, before KVM takes ownership later. The hyp-stub's
text is part of the regular kernel text, meaning it can be kprobed.

A breakpoint in the hyp-stub causes the CPU to spin in el2_sync_invalid.

Add it to the __hyp_text.

Signed-off-by: James Morse <james.morse@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm64/kernel/hyp-stub.S

index e1261fb..17f325b 100644 (file)
@@ -28,6 +28,8 @@
 #include <asm/virt.h>
 
        .text
+       .pushsection    .hyp.text, "ax"
+
        .align 11
 
 ENTRY(__hyp_stub_vectors)