Fix vgic_bitmap_get_reg function to return 'right' word address of 'unsigned long' bitmap value in case of BE 64bit image.
Signed-off-by: Victor Kamensky victor.kamensky@linaro.org --- virt/kvm/arm/vgic.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-)
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 7e11458..e56c5f8 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -96,14 +96,37 @@ static u32 vgic_nr_lr;
static unsigned int vgic_maint_irq;
+/* + * struct vgic_bitmap is union that provides two view of + * the same data. In one case it is array of registers of + * u32 type (.reg). And in another it is bitmap, which is + * array of 'unsgined long' (.reg_ul). It works all well in + * case of 32bit (u32 and 'unsigned long' have the same size). + * It works ok in 64bit LE case, where 'unsigned long' + * size is 8 bytes, while u32 is 4 bytes, and least siginificant + * word of 'unsigned long' matches lower index of .reg array. + * It breaks in 64bit BE case. In this case word sized + * register of even index actually resides in least significant + * word of 'unsigned long' which has address at offset plus 4 + * bytes. And word sized register of odd index resides at most + * significant of 'unsigned long' which has offset minus 4 + * bytes. Define REG_OFFSET_SWIZZLE that would help to + * change offset of register in case of BE 64bit system. + */ +#if defined(CONFIG_CPU_BIG_ENDIAN) && BITS_PER_LONG == 64 +#define REG_OFFSET_SWIZZLE 1 +#else +#define REG_OFFSET_SWIZZLE 0 +#endif + static u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x, int cpuid, u32 offset) { offset >>= 2; if (!offset) - return x->percpu[cpuid].reg; + return x->percpu[cpuid].reg + (offset^REG_OFFSET_SWIZZLE); else - return x->shared.reg + offset - 1; + return x->shared.reg + ((offset - 1)^REG_OFFSET_SWIZZLE); }
static int vgic_bitmap_get_irq_val(struct vgic_bitmap *x,