[v2 3/5] arm64: kdump: do not go into EL2 before starting a crash dump kernel

From: AKASHI Takahiro <takahiro.akashi@linaro.org>
To: catalin.marinas@arm.com, will.deacon@arm.com, vgoyal@redhat.com,
	hbabus@us.ibm.com
Cc: geoff@infradead.org, broonie@kernel.org, david.griego@linaro.org,
	kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org,
	linaro-kernel@lists.linaro.org, linux-kernel@vger.kernel.org,
	AKASHI Takahiro <takahiro.akashi@linaro.org>
Subject: [v2 3/5] arm64: kdump: do not go into EL2 before starting a crash dump kernel
Date: Fri, 24 Apr 2015 16:53:06 +0900	[thread overview]
Message-ID: <1429861989-8417-4-git-send-email-takahiro.akashi@linaro.org> (raw)
In-Reply-To: <1429861989-8417-1-git-send-email-takahiro.akashi@linaro.org>

Unlike normal kexec case, we don't have a chance to reset EL2 context in
a generic way because bad exceptions may directly invoke crash_kexec().
(See die().)
Kvm is not useful on crash dump kernel anyway, and so we let it
un-initialized across rebooting.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 arch/arm64/kernel/process.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index d894d3e..9859f5c 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -48,6 +48,7 @@
 #include <asm/compat.h>
 #include <asm/cacheflush.h>
 #include <asm/fpsimd.h>
+#include <asm/kexec.h>
 #include <asm/mmu_context.h>
 #include <asm/processor.h>
 #include <asm/stacktrace.h>
@@ -64,7 +65,11 @@ void soft_restart(unsigned long addr)
 	setup_mm_for_reboot();
 
 	cpu_soft_restart(virt_to_phys(cpu_reset),
-		is_hyp_mode_available(), addr);
+#ifdef CONFIG_KEXEC
+		!in_crash_kexec &&
+#endif
+		is_hyp_mode_available(),
+		addr);
 
 	/* Should never get here */
 	BUG();
-- 
1.7.9.5

