# \[PATCH AUTOSEL 5.10 50/56\] parisc: Bump 64-bit IRQ stack size to 64 KB

- From: Sasha Levin \<sashal@kernel.org\>
- Date: 2021-02-24 13:51:04 
- List: stable
- Page: https://ratatoskr.run/stable/2021/02/6277817
- Thread: https://ratatoskr.run/stable/2021/02/6277747/t.md

```text
From: John David Anglin <redacted>

[ Upstream commit 31680c1d1595a59e17c14ec036b192a95f8e5f4a ]

Bump 64-bit IRQ stack size to 64 KB.

I had a kernel IRQ stack overflow on the mx3210 debian buildd machine.  This patch increases the
64-bit IRQ stack size to 64 KB.  The 64-bit stack size needs to be larger than the 32-bit stack
size since registers are twice as big.

Signed-off-by: John David Anglin <redacted>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/parisc/kernel/irq.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index e76c866199493..60f5829d476f5 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -376,7 +376,11 @@ static inline int eirr_to_irq(unsigned long eirr)
 /*
  * IRQ STACK - used for irq handler
  */
+#ifdef CONFIG_64BIT
+#define IRQ_STACK_SIZE      (4096 << 4) /* 64k irq stack size */
+#else
 #define IRQ_STACK_SIZE      (4096 << 3) /* 32k irq stack size */
+#endif
 
 union irq_stack_union {
 	unsigned long stack[IRQ_STACK_SIZE/sizeof(unsigned long)];
-- 
2.27.0

```