[PATCH 5.10 391/575] ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc()
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-11-15 20:21:27
Also in:
lkml
Subsystem:
arm port, arm/samsung s3c, s5p and exynos arm architectures, the rest · Maintainers:
Russell King, Krzysztof Kozlowski, Peter Griffin, Linus Torvalds
From: Jackie Liu <redacted>
[ Upstream commit 2aa717473ce96c93ae43a5dc8c23cedc8ce7dd9f ]
The s3c24xx_init_intc() returns an error pointer upon failure, not NULL.
let's add an error pointer check in s3c24xx_handle_irq.
s3c_intc[0] is not NULL or ERR, we can simplify the code.
Fixes: 1f629b7a3ced ("ARM: S3C24XX: transform irq handling into a declarative form")
Signed-off-by: Jackie Liu <redacted>
Link: https://lore.kernel.org/r/20210901123557.1043953-1-liu.yun@linux.dev (local)
Signed-off-by: Krzysztof Kozlowski <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm/mach-s3c/irq-s3c24xx.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mach-s3c/irq-s3c24xx.c b/arch/arm/mach-s3c/irq-s3c24xx.c
index 79b5f19af7a52..19fb9bdf446b4 100644
--- a/arch/arm/mach-s3c/irq-s3c24xx.c
+++ b/arch/arm/mach-s3c/irq-s3c24xx.c@@ -360,11 +360,25 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc, asmlinkage void __exception_irq_entry s3c24xx_handle_irq(struct pt_regs *regs) { do { - if (likely(s3c_intc[0])) - if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) - continue; + /* + * For platform based machines, neither ERR nor NULL can happen here. + * The s3c24xx_handle_irq() will be set as IRQ handler iff this succeeds: + * + * s3c_intc[0] = s3c24xx_init_intc() + * + * If this fails, the next calls to s3c24xx_init_intc() won't be executed. + * + * For DT machine, s3c_init_intc_of() could set the IRQ handler without + * setting s3c_intc[0] only if it was called with num_ctrl=0. There is no + * such code path, so again the s3c_intc[0] will have a valid pointer if + * set_handle_irq() is called. + * + * Therefore in s3c24xx_handle_irq(), the s3c_intc[0] is always something. + */ + if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) + continue; - if (s3c_intc[2]) + if (!IS_ERR_OR_NULL(s3c_intc[2])) if (s3c24xx_handle_intc(s3c_intc[2], regs, 64)) continue;
--
2.33.0