Blame 0147-usb-ehci-Ensure-frindex-writes-leave-a-valid-frindex.patch

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From 4c245e5ecbc7d5c30c8e8bb4bfcd18c79fafddfe Mon Sep 17 00:00:00 2001
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From: Hans de Goede <hdegoede@redhat.com>
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Date: Tue, 3 Apr 2012 14:04:31 +0200
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Subject: [PATCH 147/181] usb-ehci: Ensure frindex writes leave a valid
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 frindex value
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frindex is a 14 bits counter, so bits 31-14 should always be 0, and
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after the commit titled "usb-ehci: frindex always is a 14 bits counter"
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we rely on frindex always being a multiple of 8. I've not seen this in
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practice, but theoretically a guest can write a value >= 0x4000 or a value
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which is not a multiple of 8 value to frindex, this patch ensures that
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things will still work when that happens.
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Signed-off-by: Hans de Goede <hdegoede@redhat.com>
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---
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 hw/usb-ehci.c |    4 ++++
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 1 file changed, 4 insertions(+)
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diff --git a/hw/usb-ehci.c b/hw/usb-ehci.c
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index ff69587..16e6053 100644
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--- a/hw/usb-ehci.c
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+++ b/hw/usb-ehci.c
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@@ -1081,6 +1081,10 @@ static void ehci_mem_writel(void *ptr, target_phys_addr_t addr, uint32_t val)
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         val &= USBINTR_MASK;
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         break;
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+    case FRINDEX:
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+        val &= 0x00003ff8; /* frindex is 14bits and always a multiple of 8 */
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+        break;
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+
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     case CONFIGFLAG:
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         val &= 0x1;
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         if (val) {
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-- 
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1.7.10
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