From 9125d5762590bb99d65b0f3f1c37c0585a576e67 Mon Sep 17 00:00:00 2001
From: Andreas Schwab <schwab@suse.de>
Date: Mon, 6 Jul 2020 14:32:26 +0200
Subject: [PATCH] riscv: use 16KB kernel stack on 64-bit

commit 0cac21b02ba5f3095fd2dcc77c26a25a0b2432ed upstream.

With the current 8KB stack size there are frequent overflows in a 64-bit
configuration.  We may split IRQ stacks off in the future, but this fixes a
number of issues right now.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[Palmer: mention irqstack in the commit text]
Fixes: 7db91e57a0ac ("RISC-V: Task implementation")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/riscv/include/asm/thread_info.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
index 905372d7eeb8..3df9a82bdbfd 100644
--- a/arch/riscv/include/asm/thread_info.h
+++ b/arch/riscv/include/asm/thread_info.h
@@ -12,7 +12,11 @@
 #include <linux/const.h>
 
 /* thread information allocation */
+#ifdef CONFIG_64BIT
+#define THREAD_SIZE_ORDER	(2)
+#else
 #define THREAD_SIZE_ORDER	(1)
+#endif
 #define THREAD_SIZE		(PAGE_SIZE << THREAD_SIZE_ORDER)
 
 #ifndef __ASSEMBLY__