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From: Laurent Vivier <lvivier@redhat.com>
To: qemu-devel@nongnu.org
Cc: lvivier@redhat.com, Gerd Hoffmann <kraxel@redhat.com>
Subject: [Qemu-devel] [PATCH 0/2] ohci: try to mimic real hardware command latency
Date: Wed, 16 Dec 2015 14:39:23 +0100	[thread overview]
Message-ID: <1450273165-2367-1-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.

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

 hw/usb/hcd-ohci.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

-- 
1.8.3.1

             reply	other threads:[~2015-12-16 13:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-16 13:39 Laurent Vivier [this message]
2015-12-16 13:39 ` [Qemu-devel] [PATCH 1/2] ohci: delay first SOF interrupt Laurent Vivier
2015-12-17  9:25   ` Thomas Huth
2015-12-16 13:39 ` [Qemu-devel] [PATCH 2/2] ohci: clear pending SOF on suspend Laurent Vivier
2015-12-17  9:35   ` Thomas Huth

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