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From: Laurent Vivier <lvivier@redhat.com>
To: qemu-devel@nongnu.org
Cc: lvivier@redhat.com, thuth@redhat.com, kraxel@redhat.com
Subject: [Qemu-devel] [PATCH v2 0/2] ohci: try to mimic real hardware command latency
Date: Wed,  6 Jan 2016 20:45:23 +0100	[thread overview]
Message-ID: <1452109525-32150-1-git-send-email-lvivier@redhat.com> (raw)

OHCI linux driver has some critical sections not protected against
device interrupts. Because of real hardware latency, it is generally
not a problem as interrupts cannot be triggered fast enough to happen
during these critical sections.

But theoretically, it can happen. And with QEMU used on an overcommitted
CPU, the vCPU becomes slow enough and it happens.

This series fixes a kernel crash on boot (CPU stuck) when the OHCI driver
tries to resume or suspend the device.

v2: Address comments from Thomas
    update code comments
    split ohci_sof() to add ohci_eof_timer()

Laurent Vivier (2):
  ohci: delay first SOF interrupt
  ohci: clear pending SOF on suspend

 hw/usb/hcd-ohci.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

-- 
1.8.3.1

             reply	other threads:[~2016-01-06 19:45 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-06 19:45 Laurent Vivier [this message]
2016-01-06 19:45 ` [Qemu-devel] [PATCH v2 1/2] ohci: delay first SOF interrupt Laurent Vivier
2016-01-08  7:47   ` Thomas Huth
2016-01-06 19:45 ` [Qemu-devel] [PATCH v2 2/2] ohci: clear pending SOF on suspend Laurent Vivier
2016-01-08  7:51   ` Thomas Huth

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