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Subject[PATCH 1/3] x86: UV BAU destination timeout period
Correct the calculation of a destination timeout period, which is used
to distinguish between a destination timeout and the situation where all
the target software ack resources are full and a request is returned
immediately.

The problem is that integer arithmetic was overflowing, yielding a very
large result.

Without this fix destination timeouts are identified as resource 'plugged'
events and an ipi method of resource releasing is unnecessarily employed.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
---
arch/x86/platform/uv/tlb_uv.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

Index: linux/arch/x86/platform/uv/tlb_uv.c
===================================================================
--- linux.orig/arch/x86/platform/uv/tlb_uv.c
+++ linux/arch/x86/platform/uv/tlb_uv.c
@@ -1811,8 +1811,8 @@ static int calculate_destination_timeout
index = (mmr_image >> BAU_URGENCY_7_SHIFT) & BAU_URGENCY_7_MASK;
mmr_image = uv_read_local_mmr(UVH_TRANSACTION_TIMEOUT);
mult2 = (mmr_image >> BAU_TRANS_SHIFT) & BAU_TRANS_MASK;
- base = timeout_base_ns[index];
- ts_ns = base * mult1 * mult2;
+ ts_ns = timeout_base_ns[index];
+ ts_ns *= (mult1 * mult2);
ret = ts_ns / 1000;
} else {
/* 4 bits 0/1 for 10/80us base, 3 bits of multiplier */

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