| Message ID | 20210901123557.1043953-1-liu.yun@linux.dev |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc() | expand |
Hi, krzysztof. Any suggestion? -- BR, Jackie Liu 在 2021/9/1 下午8:35, Jackie Liu 写道: > From: Jackie Liu <liuyun01@kylinos.cn> > > 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 <liuyun01@kylinos.cn> > --- > arch/arm/mach-s3c/irq-s3c24xx.c | 21 +++++++++++++++++---- > 1 file changed, 17 insertions(+), 4 deletions(-) > > diff --git a/arch/arm/mach-s3c/irq-s3c24xx.c b/arch/arm/mach-s3c/irq-s3c24xx.c > index 0c631c14a817..df471d322493 100644 > --- a/arch/arm/mach-s3c/irq-s3c24xx.c > +++ b/arch/arm/mach-s3c/irq-s3c24xx.c > @@ -362,11 +362,24 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc, > static 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; > >
On 06/09/2021 12:23, Jackie Liu wrote: > Hi, krzysztof. Any suggestion? > No, looks good, but it's a merge window time so this will wait. Best regards, Krzysztof
On Wed, 1 Sep 2021 20:35:57 +0800, Jackie Liu wrote: > From: Jackie Liu <liuyun01@kylinos.cn> > > 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. > > [...] Applied, thanks! [1/1] ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc() commit: 2aa717473ce96c93ae43a5dc8c23cedc8ce7dd9f Best regards, -- Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
diff --git a/arch/arm/mach-s3c/irq-s3c24xx.c b/arch/arm/mach-s3c/irq-s3c24xx.c index 0c631c14a817..df471d322493 100644 --- a/arch/arm/mach-s3c/irq-s3c24xx.c +++ b/arch/arm/mach-s3c/irq-s3c24xx.c @@ -362,11 +362,24 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc, static 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;