diff options
| author |   Stephen Rothwell <sfr@canb.auug.org.au> | 2008-05-21 16:24:31 +1000 |
|---|---|---|
| committer |   Paul Mackerras <paulus@samba.org> | 2008-05-23 16:15:37 +1000 |
| commit | 06a901c5621f85e07e00ac4816c7ca95620ee74a (patch) | |
| tree | 0f6a0d19d889e4209a41889ed868bc8af2a581eb | |
| parent | [POWERPC] Add kernstart_addr to list of allowed symbols in prom_init (diff) | |
| download | linux-dev-06a901c5621f85e07e00ac4816c7ca95620ee74a.tar.xz linux-dev-06a901c5621f85e07e00ac4816c7ca95620ee74a.zip | |
[POWERPC] mpic: Fix use of uninitialized variable
Compiling ppc64_defconfig with gcc 4.3 gives thes warnings:
arch/powerpc/sysdev/mpic.c: In function 'mpic_irq_get_priority':
arch/powerpc/sysdev/mpic.c:1351: warning: 'is_ipi' may be used uninitialized in this function
arch/powerpc/sysdev/mpic.c: In function 'mpic_irq_set_priority':
arch/powerpc/sysdev/mpic.c:1328: warning: 'is_ipi' may be used uninitialized in this function
It turns out that in the cases where is_ipi is uninitialized, another
variable (mpic) will be NULL and it is dereferenced. Protect against
this by returning if mpic is NULL in mpic_irq_set_priority, and removing
mpic_irq_get_priority completely as it has no in tree callers.
This has the nice side effect of making the warning go away.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
| -rw-r--r-- | arch/powerpc/sysdev/mpic.c | 20 | ||||
| -rw-r--r-- | include/asm-powerpc/mpic.h | 3 |
2 files changed, 4 insertions, 19 deletions
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c index 8619f2a3f1f6..7680001676a6 100644 --- a/arch/powerpc/sysdev/mpic.c +++ b/arch/powerpc/sysdev/mpic.c @@ -1331,6 +1331,9 @@ void mpic_irq_set_priority(unsigned int irq, unsigned int pri) unsigned long flags; u32 reg; + if (!mpic) + return; + spin_lock_irqsave(&mpic_lock, flags); if (is_ipi) { reg = mpic_ipi_read(src - mpic->ipi_vecs[0]) & @@ -1346,23 +1349,6 @@ void mpic_irq_set_priority(unsigned int irq, unsigned int pri) spin_unlock_irqrestore(&mpic_lock, flags); } -unsigned int mpic_irq_get_priority(unsigned int irq) -{ - unsigned int is_ipi; - struct mpic *mpic = mpic_find(irq, &is_ipi); - unsigned int src = mpic_irq_to_hw(irq); - unsigned long flags; - u32 reg; - - spin_lock_irqsave(&mpic_lock, flags); - if (is_ipi) - reg = mpic_ipi_read(src = mpic->ipi_vecs[0]); - else - reg = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)); - spin_unlock_irqrestore(&mpic_lock, flags); - return (reg & MPIC_VECPRI_PRIORITY_MASK) >> MPIC_VECPRI_PRIORITY_SHIFT; -} - void mpic_setup_this_cpu(void) { #ifdef CONFIG_SMP diff --git a/include/asm-powerpc/mpic.h b/include/asm-powerpc/mpic.h index 943c5a3fac8a..a4d0f876b427 100644 --- a/include/asm-powerpc/mpic.h +++ b/include/asm-powerpc/mpic.h @@ -428,12 +428,11 @@ extern void mpic_init(struct mpic *mpic); */ -/* Change/Read the priority of an interrupt. Default is 8 for irqs and +/* Change the priority of an interrupt. Default is 8 for irqs and * 10 for IPIs. You can call this on both IPIs and IRQ numbers, but the * IPI number is then the offset'ed (linux irq number mapped to the IPI) */ extern void mpic_irq_set_priority(unsigned int irq, unsigned int pri); -extern unsigned int mpic_irq_get_priority(unsigned int irq); /* Setup a non-boot CPU */ extern void mpic_setup_this_cpu(void); |