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Subject[patch v2] x86, UV: integer wrap bug in uv_hub_ipi_value()
This is a static checker fix.  The problem is that we store the bits
from "uv_apicid_hibits" into "apicid" (the high 16 bits) but then we
shift it 16 bit to the left. "apicid" is an int so it wraps and we lose
them.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: Style fix. Don't use ulong.

I don't have this hardware so I can't test it. There may also be other
bugs which this patch does not addressed. These files are only compiled
on x86_64 and "unsigned long" is used throughout to mean 64 bits.

diff --git a/arch/x86/include/asm/uv/uv_hub.h b/arch/x86/include/asm/uv/uv_hub.h
index 21f7385..e7a83d5 100644
--- a/arch/x86/include/asm/uv/uv_hub.h
+++ b/arch/x86/include/asm/uv/uv_hub.h
@@ -577,7 +577,7 @@ static unsigned long uv_hub_ipi_value(int apicid, int vector, int mode)
{
apicid |= uv_apicid_hibits;
return (1UL << UVH_IPI_INT_SEND_SHFT) |
- ((apicid) << UVH_IPI_INT_APIC_ID_SHFT) |
+ ((unsigned long)apicid << UVH_IPI_INT_APIC_ID_SHFT) |
(mode << UVH_IPI_INT_DELIVERY_MODE_SHFT) |
(vector << UVH_IPI_INT_VECTOR_SHFT);
}
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 8cfade9..6d93b2f 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -194,13 +194,13 @@ static int __cpuinit uv_wakeup_secondary(int phys_apicid, unsigned long start_ri
pnode = uv_apicid_to_pnode(phys_apicid);
phys_apicid |= uv_apicid_hibits;
val = (1UL << UVH_IPI_INT_SEND_SHFT) |
- (phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |
+ ((unsigned long)phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |
((start_rip << UVH_IPI_INT_VECTOR_SHFT) >> 12) |
APIC_DM_INIT;
uv_write_global_mmr64(pnode, UVH_IPI_INT, val);

val = (1UL << UVH_IPI_INT_SEND_SHFT) |
- (phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |
+ ((unsigned long)phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |
((start_rip << UVH_IPI_INT_VECTOR_SHFT) >> 12) |
APIC_DM_STARTUP;
uv_write_global_mmr64(pnode, UVH_IPI_INT, val);

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